. rimswm 533m. 3 ...:‘ll . . 2.. r. . , . 54% ’1 rah. I...» Vfififlflvwgfi.‘?? Wm. LARK. A. I . 13.1,: 1‘. . . pn {If grumvr‘ 9.“ .. , . ”usury. . v.‘ . 2...? u .fixfiztd. fithWJnoéJr 1-... . 3 21““; CD .23 4.: >~. Era-*5 < .. L c: "D {11.93 :41; C .93 E This is to certify that the dissertation entitled SPATIOTEMPORAL DYNAMICS OF FOREST DEGRADATION BY SELECTIVE LOGGING AND FOREST FIRE IN THE BRAZILIAN AMAZON presented by ERALDO A. T. MATRICARDI has been accepted towards fulfillment of the requirements for the degree In Geoggphy mwg (LL Major Professor’s Signature v '27 (JWL‘ Zoo? Date MSU is an affinnative-action, equal-opportunity employer PLACE IN RETURN BOX to remove this checkout from your record. TO AVOID FINES return on or before date due. MAY BE RECALLED with earlier due date if requested. DATE DUE DATE DUE DATE DUE 6/07 p:/CIRC/DateDue.indd-p.1 SPATIOTEMPORAL DYNAMICS OF FOREST DEGRADATION BY SELECTIVE LOGGING AND FOREST FIRE IN THE BRAZILIAN AMAZON By Eraldo A.T. Matricardi A DISSERTATION Submitted to Michigan State University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Department of Geography 2007 ABSTRACT SPATIOTEMPORAL DYNAMICS OF FOREST DEGRADATION BY SELECTIVE LOGGING AND FOREST FIRE IN THE BRAZILIAN AMAZON By Eraldo A T Matricardi Selective logging and forest fires have increased at a rapid pace in tropical regions in recent decades. Forest disturbances caused by selective logging and forest fires may vary in scale, ranging from local damage to forest canopy, habitats, soils, and biodiversity, to global changes caused by logging-related release of carbon into the atmosphere. This study provides a regional assessment of forest impacts by selective logging and forest fires for 1992, 1996, and 1999. Multivariate statistical models, remote sensing approaches, Geographic Information System (GIS), and remotely sensed imagery combined with field data were applied to verify the scale of environmental changes associated with these processes of forest disturbance. In this regard, the study widens the current knowledge on land use and land cover classifications to include selectively logged and burned forests as additional thematic classes. These classes have not yet been properly accounted for by conventional remote sensing approaches of deforestation assessment, despite their relevance for the understanding of the changes affecting tropical forests. This study is the first multi-temporal and spatial assessment of the selective logging and forest fire impacts in the Brazilian Amazon. The resulting estimates show that at least 11800 kmz, 16500 kmz, and 35600 km2 of natural forests were selectively logged and/or burned by 1992, 1996, and 1999, respectively. More than 60% of these forest disturbances observed in the Brazilian Amazon during those years were due to selective logging activities. However, forest fires were responsible for the greatest impacts on natural forests, causing an estimated loss of 18.8% of forest canopy in the study region. I also estimated that approximately 5467 kmz, 7618 kmz, and 17437 km2 were active areas of selective logging and/or forest fires in 1992, 1996, and 1999, respectively. In addition, approximately 4% of total forest disturbed by selective logging and forest fires was geographically located within protected areas. Areas affected by selective logging and forest fire corresponded to 2.7%, 3.2%, and 6.3% of total deforestation in the Brazilian Amazon by 1992, 1996, and 1999, respectively. Altogether, the present study demonstrated not only the importance of the selective logging and forest fires as important drivers of forest change in the tropics, but improved the existing knowledge of their combined impacts in forested lands in the Brazilian Amazon. Furthermore, the results of this research are expected to support and enhance the scope of global climate change studies associated with environmental changes caused by economic activities based on the exploitation of natural resources available in tropical forests. In terms of its applications to normative efforts, this study could be used to enlighten authorities and staff of environmental agencies working to develop sustainable management programs and environmental policies in Brazil and other tropical countries. DEDICATION Dedico esta tese a minha esposa, Cleusa, pelo seu amor incondicional, companherismo e dedicagao durante todos estes anos em terras estrangeiras, as minhas filhas, Camila e Marcela, pelo estimulo de fazer e viver sempre mais, aos meus pais, Mauro e Adelina, pela referéncia de vida pessoal, trabalho incansavel, amor e fé, aos meus irma’ios, Wagner, Hamilton e Mauro L0cio, por toda amizade, suporte e apoio incondicional, a Dona Marli, pelo amor, carinho e compreensao, ao Senhor Pedro Inocéncio (in memoriam), pela bengao e luz sobre toda minha familia, aos meus inumeros amigos no Brasil, Estados Unidos, india, Filipinas, Tailéndia, Dinamarca, Japao, etc., que me apoiaram e suportaram pacientemente durante meus estudos. N50 teria realizado todo este trabalho sem estas pessoas fazendo parte na minha vida. iv ACKNOWLEDMENTS It is very difficult to acknowledge all those who directly or indirectly supported and helped me during this academic journey. And to begin, I have no words to express my gratitude to Dr. Marcos Pedlowski for trusting, encouraging, and supporting me since the beginning of my PhD program. Thank you very much Dr. Pedlowski. I also would like to thank Dr. David Skole, my faculty advisor, for this opportunity to earn a PhD degree in the USA and for his guidance, patience, and financial support. Many thanks to Drs. Jiaguo Qi, Ashton Shortridge, and Runsheng Yin, my committee members, for the helpful lectures and advices during my PhD program and this manuscript preparation. I also thank very much the CAPES Fellowship program and the Rondonia Environmental State Secretariat for this opportunity and financial support in pursuing my PhD program at Michigan State University. I thank Dr. Mark Cochrane and Narendran Kodandapani for their help and support to accomplish my field studies in the Brazilian Amazon. Special thanks are given to Walter Chomentowski and Oscar Castafieda for their friendship and support in data processing and analysis. I would like to thank Stephen Cameron for his friendship and help during my PhD program. I would also recognize the help provided by my brothers, Wagner, Hamilton, and Mauro Lucio Matricardi, and friends Wilson Soares Abdala, Vilmar Ferreira, Daniel Gomes de Oliveira, during the fieldwork in the States of Rond6nia, Mato Grosso, and Acre. I would like to deeply recognize and thank many mateinos and picadeiros that worked very hard and helped me to successfully conduct field measurements in the Brazilian Amazon. I thank Dr. Carlos Castro, Luiz Claudio Fernandes, Antonio Lisboa, and Israel Xavier Baptista for providing data and comments on my research. I thank very much Deana Hanner and Jay Sammek for their friendship and support at Global Observatory for Ecosystem Services. I would also like to recognize the help and support in my academic pursuits by the Department of Geography, especially Dr. Antoinette Winklerprins and Dr. Richard Groop. I am especially thankful for the expertise and contribution from Drs. Asthon Shortridge, Jiaguo Qi, and Eugenio Arima, during the coursework and this manuscript preparation. Many thanks are given to Sharon Ruggles, Judy Reginek, and Marilyn Bria for their academic and administrative support at Department of Geography. I also would like to express my gratitude to Beth Weisenborn and Juliegh Bookout for the help, expertise, and good time shared during Virtual Courses. Last but not least, many thanks to my colleagues, friends, and classmates from the Global Observatory for Ecosystem Services and Department of Geography for helping me and sharing good moments during this period of time in the USA. vi TABLE OF CONTENTS LIST OF FIGURES ................................................................................ x LIST OF TABLES ....................................................... . .......................... xii LIST OF APPENDICES ......................................................................... xiv CHAPTER I Problem Statement ............................................................................................... 1 1.1 . Statement of purpose ..................................................................................... 2 1.2. Hypothesis testing .......................................................................................... 2 1.3. Background .................................................................................................... 7 1.3.1. Forest degradation concepts ................................................................ 9 1.3.2. Forest fires ......................................................................................... 11 1.3.3. Defining selective logging .................................................................. 12 1.3.3.1. Forest impacts by selective logging ............................................. 14 1.3.3.2. Impacts on carbon cycle .............................................................. 15 1.3.3.3. Impacts on biodiversity ................................................................ 16 1.3.3.4. Socioeconomic impacts ............................................................... 17 1.4. General comments ....................................................................................... 20 1.5. Overview of the study ................................................................................... 21 CHAPTER II: Methods for assessment of impacts by selective logging and forest fire: A case study in Mato Grosso, Brazil 2.1. Abstract research ......................................................................................... 23 2.2. Introduction .................................................................................................. 24 2.3. Methodology ................................................................................................. 27 2.3.1. Study site ........................................................................................... 27 2.3.2. Dataset ............................................................................................... 28 2.3.2.1. Land use and land cover dataset ................................................ 28 2.3.2.3. Selective logging dataset ............................................................. 29 2.3.2.4. Satellite imagery .......................................................................... 30 2.3.2.4.1. Radiometric and atmospheric corrections of Landsat imagery .............................................................................................................. 31 2.3.2.4.2. Normalization of seasonality effect of Landsat imagery ........ 33 2.3.2.4.3. Geometric correction ............................................................. 34 2.4. Methods ....................................................................................................... 34 2.4.1. Field measurements of forest canopy ................................................ 34 2.4.2. Remote sensing approaches ............................................................. 36 2.4.2.1. Vegetation lndices ....................................................................... 37 2.4.2.2. Modified Vegetation Index approaches ....................................... 41 2.4.2.3. Spectral Mixture Analysis ............................................................ 42 2.4.2.3.1. Endmember selection ........................................................... 44 2.4.2.4. Fractional cover ........................................................................... 46 2.4.2.5. Burned forest detection ............................................................... 47 2.4.2.5.1. Burned forest detection approach ......................................... 47 2.4.3. Forest canopy degradation assessment ............................................ 49 vii 2.4.3.1. Testing Hypotheses ..................................................................... 50 2.4.3.2. Data sampling ............................................................................. 53 2.5. Results and Discussions .............................................................................. 53 2.5.1. Relationships among various Vegetation lndices ............................... 54 2.5.2. Optimum Vegetation Index ................................................................. 56 2.5.3. Accuracy assessment of burned forest detection technique .............. 58 2.5.4. Multi-annual land use and land cover change .................................... 59 2.5.5. Assessment of forest canopy cover impacts ...................................... 63 2.6. Conclusions .................................................................................................. 67 CHAPTER III: Basin-wide assessment of forest disturbances by selective logging and forest fires 3.1 . Abstract ........................................................................................................ 71 3.2. Introduction .................................................................................................. 73 3.3. Methods ....................................................................................................... 76 3.3.1. Regional setting ................................................................................. 76 3.3.2. Dataset ............................................................................................... 77 3.3.2.1. Deforestation dataset .................................................................. 77 3.3.2.2. Selective logging dataset ............................................................. 78 3.3.2.3. Landsat imagery .......................................................................... 80 3.3.2.3.1. Radiometric correction .......................................................... 80 3.3.2.3.2. Landsat imagery normalization ............................................. 80 3.3.2.3.3. Geometric correction ............................................................. 82 3.3.3. Field study .......................................................................................... 82 3.3.3.1. Field sampling and measurement ................................................ 83 3.3.3.2. Identification of species ............................................................... 84 3.3.3.3. Data processing for biodiversity .................................................. 85 3.3.3.4. Field validation for remote sensing approaches .......................... 86 3.3.4. Remote sensing approaches ............................................................. 87 3.3.4.1. Burned forests detection .............................................................. 87 3.3.4.2. Fractional coverage ..................................................................... 88 3.3.5. Forest canopy impact assessment ..................................................... 89 3.3.5.1. Testing l-Iypotheses ..................................................................... 90 3.3.5.2. Data Sampling ............................................................................. 92 3.4. Results and Discussion ................................................................................ 93 3.4.1. Multi-temporal assessment of selective logging and forest fires ........ 93 3.4.2. Optimum vegetation index selection .................................................. 96 3.4.3. Forest canopy impact assessment based on remotely sensed data..97 3.4.4. Field measurements ........................................................................... 99 3.4.5. Links between forest canopy and further ecological indicators ........ 103 3.5. Conclusions ................................................................................................ 105 viii CHAPTER IV: Spatially explicit probabilistic models of forest fire and selective logging in the Brazilian Amazon 4.1. Abstract ...................................................................................................... 11 1 4.2. Introduction ................................................................................................ 112 4.3. Methods ..................................................................................................... 114 4.3.1. The setting ....................................................................................... 114 4.3.2. Datasets ........................................................................................... 114 4.3.2.1. Deforestation dataset ................................................................ 114 4.3.2.2. Selective logging dataset ........................................................... 1 15 4.3.2.3. Thematic maps .......................................................................... 116 4.3.2.4. Timber volume in the Brazilian Amazon .................................... 118 4.3.3. Forest Fragmentation ....................................................................... 120 4.3.4. Modeling forest fie and selective logging probabilities in the Amazon ................................................................................................................... 121 4.3.4.1. Forest fire conceptual model ..................................................... 122 4.3.4.2. Selective logging conceptual model .......................................... 127 4.3.4.3. Data sampling ........................................................................... 130 4.4. Results and Discussion .............................................................................. 132 4.4.1. Forest fire probabilistic model .......................................................... 132 4.4.2. Selective logging model ................................................................... 139 4.5. Conclusions ................................................................................................ 145 CHAPTER V: Concluding Remarks 5.1. Seating the current study in the context of global change research ........... 150 5.2. Research questions revisited ..................................................................... 154 5.3. Hypotheses revisited .................................................................................. 160 5.4. Opportunities for further studies ................................................................. 162 6. References .................................................................................................... 246 ix Figure 1.1. Figure 2.1. Figure 2.2. Figure 2.3. Figure 2.4. Figure 2.5. Figure 3.1. Figure 3.2. LIST OF FIGURES Forest production (round wood) from 1990 to 2003 in the Brazilian Amazon (adapted from IBGE, 2006) ................................................ 19 Stepwise procedure for radiometric and geometric corrections of Landsat imagery ............................................................................... 33 Procedures for calculating fractional cover ....................................... 46 Flow diagram for burned forest automated detection technique ....... 48 Land use and land cover change from 1992 to 2004 in the study site ......................................................................................................... 61 Partial effects of various forest uses on fractional coverage values in the study area estimated using linear multi-regression model and multi-annual remotely sensed derived dataset ................................. 66 Partial effects of various anthropogenic activities on forest canopy cover in the Brazilian Amazon using linear multiple-regression model and multi-temporal remotely sensed data ........................................ 98 Number of tree species, Simpson’s index of diversity, and Simpson’s reciprocal index against number of sampling (transect) ................. 101 Figure 4.1 Stratified random sampling used to collect spatial data for the probit Figure 4.2. Figure 4.3. Figure 4.4. Figure 4.5. Figure 4.6. Figure 4.7. model of forest fire and selective logging in the study region. ........ 131 Probability of forest fire with respect to distance to deforestation ...134 Probability of forest fire with respect to distance to roads ............... 135 Probability of forest fire with respect to water deficit from May to September ...................................................................................... 136 Probability of forest fire with respect to forest patch size and shape1 37 Probability of forest fire with respect to forest types, states, selective logging, protected areas, and year of analysis ............................... 139 Probability of selective logging with respect to distance to roads and timber centers ................................................................................. 141 Figure 4.8. Probability of selective logging with respect to timber volume ........ 143 Figure 4.9. Probability of selective logging with respect to states, vegetation types, protected areas, and year of analysis .................................. 144 "Images in this Dissertation are presented in color”. xi LIST OF TABLES Table 2.1. Land Use and Land Cover dataset characteristics ............................. 29 Table 2.2. Selective Logging dataset characteristics .......................................... 30 Table 2.3. Correlation matrix among various vegetation indices under smoke-free atmospheric condition for the study site .............................................. 55 Table 2.4. Correlation matrix among various vegetation indices for areas in the presence of heavy smoke in the study site. ........................................ 56 Table 2.5. Empirical linear relationship between various vegetation indices and forest canopy coverage based on field measurements in the study site ............................................................................................................ 57 Table 2.6. Accuracy assessment results of detecting burned forests using non- photosynthetic vegetation (NPV) fraction image derived from Spectral Mixture Analysis (SMA) for the study area in 2004. ............................ 59 Table 2.7. Cumulative deforestation and undisturbed and disturbed forests in the study area from 1992 to 2004. ............................................................ 60 Table 2.8. Annual increase of selectively logged forest, burned and logged forests combined, and burned forest only, from 1992 to 2004 in the study area. .......................................................................................... 62 Table 2.9. Multi-annual land use dynamics in the study site from 1992 to 2004.63 Table 3.1 Deforestation dataset characteristics .................................................. 78 Table 3.2 Selective Logging dataset characteristics ........................................... 79 Table 3.3 Detected selective logging, burned forests, and dataset characteristics ............................................................................................................ 93 Table 3.4.Total area of selectively logged and burned forests detected in 1992, 1996, and 1999 within protected areas (indigenous land, conservation unit, and military area) ......................................................................... 95 Table 3.5 Correlation matrix among various forest parameters measured in the study sites in the State of Acre, Rondonia, and Mato Grosso. .......... 104 Table 3.6. Estimated increase of new selectively logged, forests burned, and selectively logged and burned forests in the Brazilian Amazon. ....... 109 xii Table 4.1 Deforestation dataset characteristics ................................................ 115 Table 4.2 Selective Logging dataset characteristics ......................................... 116 Table 4.3. Description of the thematic maps ..................................................... 117 Table 4.4. Probit regression analysis results of forest fire ................................. 133 Table 4.5. Probit regression analysis results of selective logging ..................... 140 xiii LIST OF APPENDICES Appendix A.1. Total deforestation in the Brazilian Amazon from 1978 to 2004. 165 Appendix 8.1. Study site location (Landsat path 226 row 068) in the Amazon State of Mato Grosso, Brazil. .......................................................... 167 Appendix 8.2. Satellite imagery used in the case study in the Amazon State of Mato Grosso, Brazil. Landsat Path 226 and Row 068 ................ 169 Appendix 8.3. Slope and intercept for atmospheric correction of the Landsat imagery using as 58 model. ............................................................ 171 Appendix 8.4. Slope and intercept for normalization of the Landsat imagery using as a reference the path 226 row 068, acquired in August 8, 2001 ..................................................................................................... 174 Appendix 8.5. Fieldwork locations within the study area ...................................... 177 Appendix 8.6. Canopy openness estimation using gap light analyzer and hemispherical photos from forest canopy cover ........................... 179 Appendix 8.7. Visible and SWIR (at 2.1 pm) reflectance, and MSAVI and MSAVIaf retrieved from Landsat image acquired in 2003. .......... 181 Appendix 8.8. Burned forests detection based on non-photosynthetic vegetation fraction image .................................................................................... 183 Appendix 8.9. Cumulative deforestation and persistence of selective logging and forest fire on remotely sensed data ................................................ 185 Appendix 8.10. Forest canopy losses estimated using multi-regression model for the study area .................................................................................... 187 Appendix C.1. Study region location and Landsat scenes used in the spatiotemporal assessment of selective logging and forest fire in the Legal Amazon ............................................................................. 189 Appendix 02. Acquisition dates of the Landsat imagery for 1992, 1996, and 1 999 ..................................................................................................... 191 Appendix C.3. Case study (fieldwork) locations in the Brazilian Amazon ........... 194 Appendix 04 Case study and transect locations and characteristics ................ 196 Appendix C.5. Transect design for fieldwork measurements ................................ 198 xiv Appendix C.6. List of tree species identified and recorded during the field work in the States of Acre, Rond6nia, and Mato Grosso. ........................ 200 Appendix C.7. Estimates of indicators of forest disturbances by selective logging and forest fires based on field measurements in the States of Acre, Rond6nia, and Mato Grosso ................................................. 204 Appendix 08 Empirical linear relationship between various vegetation indices and forest canopy coverage based on field measurements for the study sites in Mato Grosso, Rondonia, and Acre. ........................ 207 Appendix C.9. Basin-wide results of selective logging and burned forest detection for 1992, 1996, and 1999 ................................................................. 209 Appendix C.10. Selectively logged and burned forests detected by State in the Brazilian Amazon .............................................................................. 212 Appendix C.11. Forest canopy losses estimated using multi-regression model for the study region ................................................................................. 214 Appendix C.12. Spatial distribution and intensity (logged area /625 km2) of selectively logged forests detected in 1992 .................................. 216 Appendix C.13. Spatial distribution and intensity (logged area / 625 km2) of selectively logged forests detected in 1996 .................................. 218 Appendix C.14. Spatial distribution and intensity (logged area /625 km2) of selectively logged forests detected in 1999 .................................. 220 Appendix C.15. Spatial distribution and intensity (burned area I 625 km2) of burned forests detected in 1992 ..................................................... 222 Appendix C.16. Spatial distribution and intensity (burned area / 625 km2) of burned forests detected in 1996 ..................................................... 224 Appendix C.17. Spatial distribution and intensity (burned area / 625 km2) of burned forests detected in 1999 ..................................................... 226 Appendix C.18. Fractional coverage derived from Landsat imagery acquired in 1992 for the study region ................................................................. 228 Appendix C.19. Fractional coverage derived from Landsat imagery acquired in 1996 for the study region ................................................................. 230 Appendix C.20. Fractional coverage derived from Landsat imagery acquired in 1999 for the study region ................................................................. 232 XV Appendix D.1. Appendix 02. Appendix D.3. Appendix 04. Appendix D.5. Appendix D6. The study region location within the Brazilian Amazon ............... 234 Deforestation map for the Brazilian Amazon in 1992, 1996, and 1999 ..................................................................................................... 236 Vegetation map of the Brazilian Amazon in 1999. ...................... 238 Map of road network, protected areas, and timber centers in the Amazon ............................................................................................... 240 Map of timber volume generated using ordinary kriging interpolation and the dataset derived from forest inventory conducted by RADAMBRASIL project ........................................... 242 Water deficit (mm) for the Brazilian Amazon during the dry season (May to September) in 1999. ............................................. 244 xvi CHAPTER I Problem Statement The highest rates of tropical deforestation (conversion of natural forests to non-forest uses) have been observed in the Brazilian Amazon in recent decades. In addition to outright deforestation, forest degradation by selective logging and forest fire has become an important issue due to its potential impacts on global environmental processes, natural ecosystems, biodiversity, and economic development. As a result, several studies have been conducted to assess impacts caused by selective logging and forest fire on tropical ecosystems. These studies have provided important direct and indirect estimates of the impacts brought by selective logging and forest fires for particular study sites in which forests have been partially damaged and not removed as in cases of deforestation. However, only a few attempts have been made to measure both the extent of selective logging and forest fires and their impacts on tropical forests using remotely sensed data gathered for the entire Brazilian Amazon. Therefore, relevant questions have yet to be addressed to provide a better understanding of selective logging and forest fire dynamics, their impacts on tropical forests, and their interactions with other land use types. For example: ls selective logging and forest fire causing more forest degradation than otherwise would occur? Can we accurately measure these anthropogenic activities in the Brazilian Amazon basin? Where are the most severe selective logging and forest fire events occurring in that region? Why are selective logging and forest fires occurring there and not somewhere else? Is there a particular spatial pattern to these activities in that region? If so, are those patterns changing over time? Is there an interaction between selective logging and fire that may be synergistically causing even more forest disturbances? 1 .1. Statement of purpose The purpose of this study is to investigate the dynamics of selective logging and forest fire processes to better understand the factors that might control these processes at various scales and times, their impacts on natural forests, and their interactions with other factors that may contribute to increase forest degradation in the Brazilian Amazon basin, using field and remotely sensed data, geographic information system, remote sensing techniques, and spatial analysis. 1.2. Hypothesis testing Hypothesis 1: Forest imficts by selective loggiggjctivities incremver time and severely disturb natu_ral forests in the Brazilian Amazon. Natural forests encompass around 3.15 million square kilometers and are the main source of raw material for timber industries in Brazil (Lentini et al., 2003). Amazonian timber production averaged 51 million cubic meters annually from 1990 to 1996, decreasing to an annual average of 17 million cubic meters from 1997 to 2003 (IBGE, 2006). Amazonian timber production and its relative contribution to national markets in Brazil have been quite steady in this period of time (see Figure 1.1). These numbers indicate that most accessible natural forests in the Brazilian Amazon have been under increasing pressure by timber industry in the last decade. Uhl et al. (1997) observed that loggers are advancing into undisturbed forests and are re-logging previously disturbed forests searching for second tier economic species. Matricardi et al. (2007) estimated that the total area of selective logging detected with satellite imagery increased about 436% between 1992 and 1999 in the Amazon. Based on a case study in the state of Mato Grosso, Matricardi et al. (2005) estimated that areas of formerly logged forests that were re-logged increased 1442% between 1993 and 2002. Consequently, it is expected that forest degradation in the Brazilian Amazon has also increased as a consequence of the growth in area and intensity of selective logging activities. If this hypothesis is true, both selective logging impacts on natural forests and degraded forests have significantly increased over time. For the present study, this hypothesis was tested at local and regional scales, focusing on areas where selective logging has been detected using remotely sensed data. At the local scale, a multi-temporal assessment of selective logging impacts was conducted in the Southeastern Amazon using 13 years (1992 to 2004) time-series remotely sensed data and field measurements (i.e. forest regeneration, number of tree species and mortality, and fuel load). This case study sought to contribute to a better understanding of the annual change in degradation rates and the capacity for forest regeneration in areas affected by selectively logging. Additionally, fieldwork activities were carried out to validate remote sensing techniques in different study sites in the Amazon region. At the regional scale, fractional coverage was estimated for areas where selective logging has been detected using Landsat imagery for three different years (1992, 1996, and 1999). These results provided estimates of impacts and temporal changes in canopy degradation and regeneration of selectively logged forests in the Brazilian Amazon. Multiple regression analysis was used to statistically infer the contribution of each land use type on forest disturbances at local and regional scales. Additional statistical tests were applied to assess forest disturbances based on field measurements for different land use types. Hypothesis 2: Forest fires mostly occur on fire-prone selectively logged forests and further increage forest degrfllation in the Brazilian Amazon. Selective logging activities can severely impact tropical forests by damaging individual trees and under-story vegetation, compacting and eroding soils (Verissimo et al., 1992, Johns et al., 1996), reducing canopy cover (Uhl and Vieira, 1989, Verissimo et al., 1992), and, potentially, increasing forest fire susceptibility (Holdsworth and Uhl, 1997), especially during years of severe droughts (Uhl and Kauffman, 1990). Uhl and Buschbacher (1985) were the first to observe a synergistic interaction between selective logging and fire-maintained pastures where fire spreads into logged forests. It was then hypothesized that most forest fires were occurring on previously logged forests, and forest fires were spatially associated with logging and deforestation areas; forest degradation would be significantly higher when selective logging was combined with forest fire. This hypothesis was tested at local and regional scales. At the local scale, a study site in Mato Grosso where fire hotspots have been more frequently observed using NOAA and MODIS imagery (INPE, 2007) was studied. First, burned forests were detected using a Landsat time-series imagery (1992 to 2004) and a new remote sensing method based in part on Cochrane and Souza (1998) was applied. This method involved masking out non-forest areas and applying linear mixture model classification to detect burned forests. Linkage between selective logging and forest fires was demonstrated by juxtaposing selectively logged and burned forests. Moreover, fractional coverage was calculated for both selectively logged only and selectively logged/burned forests. This procedure helped to estimate forest canopy losses and time required for forest regeneration under different land use characteristics (i.e. burned and non- burned forests). Temporal changes were assessed by comparing data from 1992 to 2004. Finally, field measurements (i.e. forest regeneration, number of tree species, trees mortality, and fuel load) were also conducted on disturbed and undisturbed forest sites to provide additional information on forest degradation. At the regional scale, burned forests were detected for three years (1992, 1996, and 1999) using the same methodological approaches applied and validated at the local scale analysis. Fractional coverage was estimated for areas where selective logging has been detected using Landsat imagery. These datasets were mostly derived from remotely sensed data and focused on areas where evidences of selective logging and forest fire had been previously observed in the study region. Hypothesis 3: Variables that reflect landscape and land use chiacten'stics (ea. vegetation type. soil. precipitation. deforestation. forest fragmentation, proximity to ad network. etc.) explain spatial distribution and probaLiIitv of selective logging and forest fire to occur in the Brazilian Amazon. Links between selective logging and various socioeconomic and biophysical factors have been studied by many authors. (Uhl and Vieira, 1989) affirrned that access roads left behind by selective logging activities contribute to increase deforestation in new frontiers. Furthermore, fire-maintained agricultural systems may spread out into adjacent logged forests (Uhl and Buschbacher, 1985). More recently, (Cochrane et al., 2004) observed that there are synergistic interactions between different anthropogenic activities (eg. selective logging and fire, deforestation and forest fragmentation, etc.) potentially increase forest degradation. Particularly, this analysis focused on existing variables derived from remotely sensed data for a sub-region within the Amazon basin where selective logging and forest fire were more evident on satellite imagery, and excluded those areas where this type of activity were improbable. Therefore, it was expected that variables such as forest and soil types, proximity to roads, precipitation regimes, land tenure (private and public lands), proximity to urban areas, and proximity to previous deforestation events could play important roles in explaining the spatial patterns of selective logging and forest fire in the study area. It was also expected that temporal changes in spatial patterns of selective logging and forest fire in the study area could be explained by the use of a multi- temporal dataset (i.e. 1992, 1996, and 1999). Multivariate probit models were applied to assess which factors were influencing the spatial distribution of selective logging and forest fire. This analysis, however, required several attempts and different variables to estimate probability of selective logging and forest fire in the study region. This procedure was intended to select statistically significant variables that represented factors influencing selective logging and forest fire occurrences in the study area. The final statistical models were expected to significantly explain both the selective logging and forest fire probabilities throughout the study region. 1.3. Background The Brazilian Amazon contains 40% of the Earth’s remaining tropical rainforests and plays an important role in sustaining biodiversity, regional hydrological regimes, climatic patterns (Fearnside, 1999), and terrestrial carbon pools (Fearnside, 1999, Houghton et al., 2000). Consequently, the increasing rates of deforestation in the Brazilian Amazon has become an environmental concern of global dimension (Laurance et al., 2001, Nepstad et al., 2002). Multi-annual estimates of deforestation in the Brazilian Amazon provided by the National Institute for Space Research - INPE, show that total deforestation was 152,200 kmz, 377,500 sz, and 551,782 km2 by 1978, 1988, and 1998, respectively. Such estimates represent an annual increment of 19,979 kmz, an increase of 362% since 20 years ago (the world’s highest absolute rate of deforestation). Most recent measurements based on remotely sensed data show that 703,198 sz were deforested by 2005 (Appendix A.1), equivalent to 14.06% of the total legal Brazilian Amazon (INPE, 2007). Satellite-based remote sensing has been used for several decades to monitor and to evaluate land use and land cover changes in the Amazon, focusing most on deforestation assessments (Fearnside et al., 1990, Skole and Tucker, 1993). Data from these studies (eg. rate of deforestation in Brazil’s Legal Amazon) are often used to estimate human effects on the global carbon cycle (Fearnside, 1997, Houghton, 1997, Houghton et al. 2000). However, there is evidence that approximately half of the total area of forest damaged or impoverished annually by human activities has not been detected under conventional deforestation classification schemes and, consequently, the total area of disturbed forests has been greatly underestimated. Most of those non- detected areas are related to forest degradation caused by selective logging and forest fires (Cochrane et al., 1999, Nepstad et al., 1999). Earlier studies (Stone and Lefebvre, 1998, Souza and Barreto, 2000, Asner et al., 2002) in the Brazilian Amazon state of Para have shown that it is possible, with some limitations, to detect selective logging using remotely sensed data. Matricardi (2003) expanded the scope of these studies by identifying and mapping areas of selective logging in tropical “terra-finne” (high land) forests for the entire Amazon basin for three different years. Matricardi showed that at least 3,689 sz, 5,107 sz, and 11,638 sz of natural forests had being actively logged in 1992, 1996, and 1999, respectively. More recently, additional attempts to automatically detect selective logging and its impacts on tropical forests using remote sensing techniques have been conducted in different parts of the Brazilian Amazon. Souza et al. (2003) and Asner et al. (2004) provided valuable information based on different case studies in the state of Para. Matricardi et al. (2005) also conducted a multi-temporal analysis, from 1992 to 2002, in the state of Mato Grosso. Although these studies have significantly improved detection techniques and current understanding of selective logging for specific sites, its impacts, spatial patterns, and temporal dynamics over the entire region have yet to be assessed. This research sought to enhance the understanding of the spatial patterns and temporal changes of forest degradation associated with selective logging and forest fires, the interactions between selective logging, forest fires, and other land use types, and how forests ecosystems respond to these anthropogenic activities. A final goal was to provide support for prognostics of selective logging and forest fire spatial trends throughout the Brazilian Amazon region. 1.3.1. Forest degradation concepts The term forest degradation has been defined as a ‘temporary or permanent deterioration in the density or structure of vegetation cover or its species composition’ (Grainger, 1993). Unlike deforestation, this term has been used to describe disturbances in forest characteristics that do not involve land cover conversion into other land cover types (Grainger, 1999, Lambin, 1999) and that may occur in a short or long-run time-scale (Lambin, 1999). In the Amazon, anthropogenic forest degradation is often related to forest fragmentation (Skole and Tucker, 1993, Cochrane, 2001), selective logging (Pinard and Putz, 1996, Lambin, 1999, Nepstad et al., 1999, Huth and Ditzer, 2001), and forest fires (Uhl and Buschbacher, 1985, Cochrane and Schulze, 1998, Cochrane et al., 1999). More specifically, forest fragmentation is normally associated to different forms of deforestation or clear-cutting, whether involving conversion of forest for agriculture or infrastructure development, because it increases forest disturbances along the edges of those remaining forests within deforested areas (Skole and Tucker, 1993, Lambin and Ehrlich, 1997, Laurance et al., 1997). Forest disturbances tend to be higher at the edges because of the increased amounts of sunlight and wind that penetrate the forest, causing, among other things, increased tree mortality (Laurance et al., 1997) and increased drying rates of leaves and wood debris on the forest floor (Nascimento and Laurance, 2002). Ultimately, such effects increase forest fire susceptibility. Concomitantly, frequent exposure of fragmented forest edges to agricultural fires increases the risk of forest fires (Laurance et al., 1997). As a result, forest fire is another important proximate cause of forest degradation. Although tropical forests were until recently deemed as immune to fire (Uhl and Kauffman, 1990, Cochrane and Schulze, 1998), forest fires have been increasing as the deforestation and forest fragmentation increase. Deforested areas display greater risk to fire and often act as ignition sources for fragmented forest sites that have lost their immunity to fire infiltration (Uhl and Kauffman, 1990, Cochrane and Schulze, 1998, Cochrane, 2001, Cochrane et al., 2004). Selective logging also increases forest degradation. Although this economic activity involves cutting down only the few most marketable trees in tropical forests, it can severely impact undisturbed forests during the harvesting operations (Pinard and Putz, 1996, Uhl et al., 1997, Nepstad et al., 1999, Huth and Ditzer, 2001). Thus, the combined effects of selective logging, forest fragmentation, and forest fire can dramatically increase forest degradation rates 10 in tropical regions (Cochrane et al., 2004). A focus on degradation thus expands the previous discussions on deforestation alone. Further details on selective logging impacts on natural forests are presented subsequently. 1.3.2. Forest fires Previous studies had shown that forest fires rarely occur in intact tropical forests. Fire events should be unexpressive in most of the Brazilian Amazon (Uhl and Kauffman, 1990, Cochrane and Schulze, 1998) because of moist microclimates provided by tropical forests that make it difficult for the propagation of fires, even during dry season periods (Uhl and Kauffman, 1990). In spite of this expected resistance to fire, the spread of forest fire is a growing concern in many tropical countries. Uhl and Buschbacher (1985) suggested that there is a direct relationship between agricultural practices that use fire for land maintenance, such as clearing woody debris and weed control, and increased forest fire susceptibility particularly on logged sites close to agriculture. Accordingly, agricultural plots have been designated as the most common fire triggers in the Brazilian Amazon (Uhl and Buschbacher, 1985, Uhl and Kauffman, 1990, Cochrane, 2001). In fact, there is a growing probability of fires in tropical forest as the forest become more fragmented by selective logging and the edge formation along forest and deforested areas (Cochrane, 2001). Forest fires are devastating for tropical ecosystems because of their natural low resistance to fire, which allows dominance by thin bark trees (Uhl and Kauffman, 1990). Moreover, once a site is burned for a first time, increase chances for recurring fire and more intense fires 11 because of increased fuel loads and drier microclimate created by the previous fire (Cochrane and Schulze, 1998). Therefore, sequential fires can degrade forests rapidly by drastically destroying their structure and composition and, ultimately, creating a new land cover type whose structural features resembles a secondary regrowth and not an actual pristine tropical forest. 1.3.3. Defining selective logging The term selective logging is used to define the targeted extraction of a group of tree species in which, usually, the most economically valuable trees are removed from the forest (Verissimo et al., 1995, Uhl et al., 1997). While deforestation in tropical areas affects directly the carbon cycle and causes massive destruction of plants and animals by clear-cutting and burning natural forests (Skole and Tucker, 1993), selective logging activities do not clear- cut and burn forests, but harvest only a portion of trees. In spite of being a less aggressive form of forest intrusion than clear-cutting, selective logging can damage a large portion of forest and affect many trees during logging operations (Pinard and Putz, 1996, Nepstad et al., 1999, Huth and Ditzer, 2001). For instance, when traditional techniques are used, the harvesting of a single tree alone can directly result in the death of thirteen other trees as result of its fall direction, and, in addition, ordinary logging operations such trail opening, acess road construction, and the establishment of log storage patios also contribute to increase forest degradation (Verissimo et al., 1992). Meanwhile, selective logging activities have been occurring in Brazil’s tropical forests for several decades (Uhl and Kauffman, 1990, Stone and 12 Lefebvre, 1998, Nepstad et al., 1999, Alvarado and Sandberg, 2001). These activities have been traditionally restricted to flood plains (vérzeas) due the pre- existent access through the rivers (fluvial transportation). However, the expansion of road networks during 1960s and 19705 in the Brazilian Amazon allowed the expansion of selective logging to the interfluvial (terra finne) forest areas (Uhl and Vieira, 1989, Uhl et al., 1997). Moreover, the Avanca Brasil1 program set by the Federal government to strengthen transportation networks in the Brazilian Amazon as a mean to further accelerate economic development (eg. roads, timber and mining industry) in the region is expected to have major impact on the diffusion of logging operations (Laurance et al., 2001, Fearnside, 2002) Selective logging can be classified in terms of spatial distribution and severity. Spatially, selective logging can occur in ‘varzeas’ and ‘tene firme’ in the Brazilian Amazon. Moreover, selective logging varies in terms of impacts (i.e. low, moderate, and high), depending on the volume and number of harvested trees (Uhl et al., 1997). Low impact logging (i.e. highly selective logging) involve the extraction of one or two high valuable tree species, such as Virola (Virola sun'namensis (Rol.) Warb ) (Uhl et al., 1997) and Mahogany (Swietenia macrophylla, King) (Verissimo et al., 1995, Uhl et al., 1997). On the other hand, 1 “Avanca Brasil" (Fonrvard Brazil) is a development program that is being conducted by the Brazilian government in the Brazilian Amazon, involving a total of US$ 43 billion over the 2000- 2007 period of which US$20 billion is for infrastructure such as transportation corridor expansion (roads, water ways, and railways) with direct impacts on the (Laurance et al. 2001, Feamside 2002). 13 high impact logging encompasses a hundred or more tree species, and requires the use of heavy machinery and the construction of greater infrastructure (i.e. patios, forest roads, etc.) for tree harvesting and transportation. The later form of selective logging is the most common form in the more developed parts of the Brazilian Amazon (Uhl et al., 1997). Finally, (Uhl et al., 1997) described an additional logging type of logging known as forest ‘mining’, actually a sequential form of selective logging. Forest mining can completely impoverish a seemingly intact forest tract over a period up to thirty year of successive and ever more intensive selective logging activities that at the end may lead to an acute form of forest degradation or even outright deforestation. 1.3.3.1. Forest impacts by selective logging Selective logging activities leave behind a mixture of intact forest, treefall gaps, roads, log-loading patios, and damaged forests, increasing amounts of dead slash or dried biomass (fuel) and, consequently, greater risks of forest fire events (Uhl and Buschbacher, 1985, Stone and Lefebvre, 1998, Nepstad et al., 1999, Souza and Barreto, 2000). Estimates of the total of damages arising from logging operations point out that about 40% of the remaining trees in a given forest patch affected by selective logging may end either killed or severely damaged (Uhl et al., 1991). Such impacts can be devastating even when a small volume of timber is harvested (Frumhoff, 1995). The potential impacts of selective logging in tropical forest ecosystem are further discussed bellow. 14 1.3.3.2. Impacts on carbon cycle (Skole and Tucker, 1993) have argued that “tropical deforestation is a major component of the carbon cycle and has profound implications for biological diversity”. The greatest carbon and biodiversity losses happen when a forested area of high biomass content is converted into a low biomass system such as pasture and agriculture, releasing carbon directly to the atmosphere and destroying natural habitats (Skole and Tucker, 1993). Nevertheless, Amazonian forests are increasingly being exposed to logging activities (Stone and Lefebvre, 1998, Nepstad et al., 1999, Souza and Barreto, 2000). Although the impacts of selective logging are known to vary according to extraction intensity, their overall impacts are usually substantial on the complex and fragile tropical environments. Meanwhile, selectively logged forests are expected to accumulate carbon over time and return to pre-harvest levels of biomass if left undisturbed. However, many forests are revisited several times by loggers seeking to harvest additional tree species as regional timber markets evolve (Verissimo et al., 1995, Uhl et al., 1997). Re-Iogged forests become highly degraded and may have 40 — 50% of the canopy cover is destroyed during these re-logging operations (Uhl and Vieira, 1989, Verissimo et al., 1992). In addition, forest heavily impacted by selective logging are expected to face an increase in fire susceptibility (Holdsworth and Uhl, 1997) and, consequently, more emissions of carbon to the atmosphere (Houghton, 1997). Intentionally or not, uncontrolled forest exploitation by loggers also serve to catalyze deforestation by opening roads inside idle public lands and protected 15 areas that are often squandered by large ranchers and small farmers. This process results in increased rates of deforestation and higher carbon emissions to the atmosphere (Verissimo et al., 1995). 1.3.3.3. Impacts on biodiversity Upper Amazonian forests are considered to be one of the world’s richest biomes in terms of plant and animal diversity (Gentry, 1988). Although during selective logging only a few valuable tree species are harvested, high intensity logging can heavily impact a whole forest ecosystem (Frumhoff, 1995) including damage to nearby trees and soils (Uhl and Buschbacher, 1985, Johns et al., 1996) and increased risk of local species extirpation (Martini et al., 1994). Furthermore, hunters gain greater access through the logging road network, which increases both commercial and subsistence hunting, usually aimed at primates and duikers (Frumhoff, 1995). Therefore, impacts by selective logging may affect both plant and animal species, especially those associated with the timber species (eg. mammals and birds that eat timber specie fruits) (Martini et al., 1994). (Frumhoff, 1995) affirrned that the ecosystem changes caused by selective logging result in loss of equilibrium in animal population in terms of number of species and species diversity, with some species tending to become more abundant than others because of hunting. In terms of plant populations, selective logging eliminates the most valuable timber species and, systematically, reduces the number of most fit individuals and, therefore, preclude sustainable species reproduction (Uhl and Vieira, 1989). 16 Selective logging activities also cause losses in the forest structural integrity and lead to further degradation, especially in open canopy forest patches with presence of vines (Uhl and Buschbacher, 1985). Therefore, although selective logging in the Amazon floodplain concentrates on very few species, it results in profound ecological changes. (Macedo and Anderson, 1993) observed a dramatic transformation in the under-story vegetation as a result of selective logging, with the development of secondary vegetation predominantly formed by vines and herbs. Other environmental changes commonly associated to selective logging include the development of drier conditions within logged patches (Martini et al., 1994) and soil compaction (Pinard and Putz, 1996, Fredericksen and Pariona, 2002). Meanwhile, habitat modifications directly affect the distribution and abundance of amphibians and reptiles, seed dispersion, and forest regeneration (Martini et al., 1994). The extended effects of selective logging, including the decrease in forest yield, can lead to outright forest conversion to other land use types (Pinard and Putz, 1996, Huth and Ditzer, 2001), which implies the complete destruction of a given natural forest patch. 1.3.3.4. Socioeconomic impacts The Brazilian economy was placed among the 10 largest economies in the world in 2000, with a Gross Domestic Product (GDP) of US$ 596 billion. Alone, the timber sector contributed with approximately 5.5 billion to the Brazilian GDP (ABIMCI, 2002). In the Brazilian Amazon, the timber industries are responsible for approximately 15% of the regional GDP and employ 5% of the regional workforce (World Bank, 1999). It is estimated that 61.1% of the total of effective 17 productive native forests are located in the Brazilian Legal Amazon, placing the region as the main source of raw materials for the Brazilian timber industry (ABIMCI, 2002). In addition, according to (IBGE, 2006), from the country’s reported2 timber production between 1990 and 2003 a total around of 445 million cubic meters of round wood was extracted in the Brazilian Amazon states, an average around of 34.2 million m3 yr". The Brazilian Amazon alone produced approximately 80% of national round wood production in Brazil over this time (Figure 1.1). Based on the census data provided by lBGE (2006), approximately 74% of the timber production in the Brazilian Amazon from 1990 to 2003 was extracted in the state of Para, 10% in the state of Amazonas, and 8% in the state of Mato Grosso. Although this overall round wood production results place the State of Amazonas as the second timber producer in the region, the State of Mato Grosso has occupied this place from 1991 to 2003, immediately followed by the states of Rondonia and Amazonas (IBGE, 2006). As a result of an abundant timber resource pool, selective logging related activities enhance the local economy. (Verissimo et al., 1992) observed that 112 sawmills in the vicinity of the city of Paragominas in Para, generated approximately 5,700 jobs, including forestry workers (e.g. forest timber extractors, truck drivers, machinery operators, etc.) and industrial workers. 2 Total of round wood production reported by timber industries to the Brazilian Institute for Environment and Natural Resources - IBAMA (IBGE, 2005). 18 Verissimo and collaborators observed that more than 50% of the urban population of Paragominas was directly dependent of the timber industry for income generation. A major indirect impact of the timber industry is the creation of significant tax revenues, which can be used for the benefit of the local and regional population. Figure 1.1. Forest production (round wood) from 1990 to 2003 in the Brazilian Amazon (adapted from IBGE, 2006) Timber-based local economies are subject to collapse, however. Pinedo- I 90,000 100 80,000 § 70,000 2 60,000 - ~~ - - -- -~~ 70 Q .2. 50,000 ~ I, --/ r" ‘3‘ j :3 9:; , ,. f; 40,000 ~— «’7‘ ~ ~ —~—: 40 g 2 30,000 ~—-- - ~ ~ A— 2- 30 > > 20,000 *..‘_'_I, ,,. 9:731” 20 10,000 — — ~=L 10 aasssssaasssss e—It—uv—nt—nv—cv—r—n—r—Iv—tNNNN + Amazon round wood production + Amazon/Brazil round wood production (%) Vasquez et al. (2001) conducted a study case in a floodplain forest in the State of Amazonas, following a logging “boom” . In this case, the local timber industry collapsed after the high value timber species were exhausted, leading industries and individuals to migrate to other regions seeking new sources of raw material and job opportunities, respectively. 19 Uhl and Vieira (1989) observed some indirect socio-economical impacts of selective logging. Uhl and Vieira suggested that forest access roads left behind after selective logging activities lead to the occupation of new areas by landless peasants, increasing deforestation and threatening indigenous communities. Furthermore, Uhl and Buschbacher (1985) observed that fire used by farmers in the Amazon region to manage crops and pastures often spread into adjacent forests. In contrast to non-logged forest, fire spreads readily in exploited forest causing extensive damage. 1.4. General comments A great number of articles available in the literature have been used to support analyzes regarding the impacts by selective logging and forest fires in the Brazilian Amazon. This body of literature has contributed to create a conventional wisdom that characterizes these anthropogenic activities as major drivers of forest degradation in tropical regions. For example, Feamside (1997) and Uhl and Vieira (1997) affirmed that logging often leads to significant losses in canopy and biomass content. Furthermore, Holdsworth and Uhl et al. (1997), Cochrane (1999), and Cochrane and Schulze (1999) observed that selective logging leads to a significant increase in the number of forest fires in tropical ever green forests. Meanwhile, Nepstad et al. (1999) have estimated areas impacted by logging based on records of sawmills’ production because they believed that logging was cryptic and, therefore, could not be adequately resolved by the usage of remotely sensed data. In addition, these authors had never directly measured the extent of selective logging at the regional scale. Nonetheless, 20 Nepstad et al. (1999) combined these studies and concluded that selective logging is highly significant, equal or more than deforestation to explain forest degradation in tropical countries. Another major conclusion of Nepstad and his colleagues was the lack of reliable measurements of the combined impacts of selective logging and forest fires in the Brazilian Amazon. In my research, one of my main goals was to investigate the validity of the existent conventional wisdom about the extent and impacts of selective logging and forest fires in the Amazon region. To achieve this goal I created a methodological framework to quantify forest degradation at local and regional scales by examining the spatial characteristics and the temporal changes of selective logging and forest fires. I also investigated the factors controlling the processes of forest degradation at various geographical and temporal scales in the Amazon basin. 1.5. Overview of the study This manuscript was divided into five chapters to address the previously stated research purposes. Chapter I presents the research design and describes the general scientific development of the study. Chapter II focuses on the development of remote sensing and statistical analysis approaches used to assess extent and impacts by selective logging and forest fires in a case study in the southwestern Amazonian state of Mato Grosso. Chapter III shows the application of the scientific approaches developed in Chapter II to a basin wide assessment of both the extent of selective logging and forest fires and their impacts on Amazonian forests. Chapter IV shows the development and 21 implementation of spatiotemporal analyzes of selective logging and forest fires using probabilistic probit models at the regional scale in the Brazilian Amazon. Finally, Chapter V summarized analyses presented in the previous chapters by revisiting all research questions and hypotheses, and by connecting all research findings to the global change context. Finally, I concluded by presenting the potentials raised by this study for further inquiries on the processes controlling the pace of environmental changes in the Brazilian Amazon. 22 CHAPTER II Methods for Assessment of Impacts by Selective Logging and Forest Fire: A Case Study in Mato Grosso, Brazil 2.1. Abstract research Many studies have been conducted to assess the process of forest degradation in the Brazilian Amazon. Several of those researches relied on remote sensing approaches to estimate the extent and impact by selective logging and forest fires on tropical rain forest. However, only a few studies assessed the combined impacts of those anthropogenic activities. I conducted a detailed analysis of selective logging and forest fire impacts on natural forests in the Southern Amazon State of Mato Grosso, Brazil, one of the key logging centers in Brazil. I used a 13-year series of annual Landsat images (1992-2004) to test different remote sensing techniques for measuring the extent of selective logging and forest fires and their impacts and interactions with other land use types in the study region. I also assessed forest canopy regeneration following these disturbances. Field measurements and observations were conducted to validate remote sensing approaches. The results indicated that the Modified Soil Adjusted Vegetation Index aerosol free (MSAVIaf) is a reliable estimator of fractional coverage under both clear sky and smoke conditions in this study region. Multi- temporal analysis of land use and land cover change from 1992 to 2004 indicated that around of 29% of the study area had been converted into agricultural land by 2004. In terms of extent, selective logging activity was the most important forest disturbance factor, impacting more than 31% of the total 23 study area by 2004. Approximately 28%, 5%, and 3% of the study area was impacted by deforestation, selective logging and forest fire combined, and forest fire only, respectively. Although selective logging impacted the largest extent of natural forest in the period of analysis, more than 35% and 28% of the observed forest canopy losses were due to forest fire and selective logging combined and to forest fire only, respectively. These study results also indicated that approximately 70% of total area of forest disturbed by logging and fire had sufficiently recovered to become undetectable on satellite imagery in 2004, which implies that selectively logged and burned forests may transition from a carbon sources to carbon sinks in the subsequent years due to strong forest regeneration. This type of forest degradation is an addition to outright deforestation analysis and has yet to be accounted for. Finally, the results of this research could be useful to global climate change analysis, sustainable forest management programs, and environmental policy development in Brazil. 2.2. Introduction Selective logging activities have been occurring in Brazil’s tropical forests for several decades (Stone and Lefebvre, 1998, Nepstad et al., 1999, Alvarado and Sandberg, 2001). Logging activities were restricted to flood plains (véizeas) until the 1960s due to the pre-existent access though rivers (fluvial transportation) in areas flooded annually, but the widespread construction of roads during the 1960s and 1970s allowed the expansion of selective logging into the inter-fluvial (terra-firme) forest in the Brazilian Amazon (Uhl and Vieira, 1989, Uhl et al., 1997). 24 As a result of increased access provided by roads, selective logging has become a major environmental concern in the Brazilian Amazon due to its potential negative effects on natural forests. Selective logging is a form of timber extraction of a select group of tree species where only the most valuable tree species are removed from the forest (Verissimo et al., 1995, Uhl et al., 1997). Selective logging activities leave behind a complex landscape comprised of intact forest, treefall gaps, roads, log-loading patios, and damaged forest. These activities increase the amount of dead slash or dried biomass (fuel) and, consequently, forest fire susceptibility is substantially increased (Uhl and Buschbacher, 1985, Stone and Lefebvre, 1998, Nepstad et al., 1999, Souza and Barreto, 2000). The impacts caused by logging in tropical forests are significant in terms of forest degradation and fire susceptibility (Uhl and Buschbacher, 1985, Stone and Lefebvre, 1998, Nepstad et al., 1999, Souza and Barreto, 2000). Selectively logged forests become highly degraded and usually have 40 — 50% of the canopy cover destroyed during logging operations (Uhl and Vieira, 1989, Verissimo et al., 1992). Forests heavily impacted by selective logging will have a significant increase in the level of forest degradation and fire susceptibility (Holdsworth and Uhl, 1997, Stone and Lefebvre, 1998, Cochrane, 2001). Not surprisingly, forest fires have been increasing in the Brazilian Amazon, and are more common in fragmented forests located next to deforested areas, which serve as ignition sources of forest fire (Uhl and Kauffman, 1990, Cochrane and Schulze, 1998, Cochrane, 2001, Cochrane et al., 2004). 25 Most studies on the impacts of selective logging that relied on remotely sensed data quantified forests affected by selective logging were conducted for study sites in Eastern Para, Brazil, using Landsat images and visual interpretation. For example, Souza and Barreto (2000) conducted an investigation using a linear mixture model and Landsat imagery to detect logging patios within selectively logged forests in a study site in the State of Para, Brazil. Cochrane and Souza Jr (1998) developed a remote sensing technique to detect and classify burned forests using non-photosynthetic vegetation derived from Linear Mixture Analysis for a study site in Tailandia, Amazon State of Para. Cochrane and Sousa Jr (1998) and Cochrane et al. (1999) conducted field studies and a multi-temporal analysis of remotely sensed imagery to understand forest fire dynamics in a study site in the Amazon state of Para, Brazil. Souza et al. (2003) developed a methodology to map classes of degraded forest for a study case in the State of Para using fraction images (vegetation, non- photosynthetic vegetation, soil, and shade) derived from spectral mixture models. More recently, Souza et al. (2005) conducted an evaluation of different vegetation and infrared indices and fraction images derived from spectral mixture analysis in assessing multi-temporal forest degradation within nineteen transects in the eastern Amazon. Matricardi et al. (2005) estimated areas of selectively logged forests throughout an entire Landsat scene in the State of Mato Grosso, Brazil, by combining fieldwork and remote sensing approaches. Although these previous studies significantly improved remote sensing approaches to assess both extent and impacts caused by selectively logging and 26 forest fires using remotely sensed data in tropical forests, they have focused on particular study sites, a more comprehensive assessment of forest disturbances by forest fire and selective logging and their interactions with other land use and land cover processes have yet to be conducted. Moreover, atmospheric changes caused by smoke derived from deforested and forested areas have limited multi- temporal analysis using remotely sensed data (Karnieli et al., 2001, De Moura and Galvao, 2003). To address these scientific gaps, I conducted field observations and tested performance of different vegetation indices and a green vegetation fraction (GV) derived from Spectral Mixture Analysis (SMA) to assess forest canopy degradation in the presence of smoke. I also improved the Modified Soil-Adjusted Vegetation Index (MSAVI) to MSAVI_af (MSAVI aerosol-free). In addition, I developed an automated remote sensing approach to map burned forest using non-photosynthetic vegetation (NPV) fraction derived from SMA. Finally, I conducted a multi-annual analysis of forest canopy degradation in the study area that provided useful information to assess forest impact and forest regeneration for years following selective logging and forest fire events. Spatial interactions between burned and selectively logged forests were also examined. 2.3. Methodology 2.3.1. Study site This research was conducted using one Landsat scene (path 226 and row 068) that encompassed approximately 30,000 km2 in the State of Mato Grosso, Southern Brazilian Amazon (see Appendix 8.1). The study area includes the 27 municipios of Santa Carmem and Uniao do Sul and parts of the municipios of Colider, Feliz Natal, ltaI'Jba, Marcelandia, Nova Ubirata, Paranatinga, Sinop, Sorriso, and Vera, which form a territory known as the Sinop region. The climate in the study area is humid tropical with very distinct dry and wet seasons that extend from June through September and from December through March, respectively. The average annual precipitation and temperature is 2000 mm and 26° C, respectively (RADAMBRASIL, 1980). Prior to modern colonization the study area was mostly covered by transitional forests, a semi- deciduous forest type, with emergent can0py. However, by 2004 approximately 8,500 km2 of native forest had been converted into extensive soybean plantations and pasture. Nonetheless, the Sinop region remains a major timber center in the Amazon in spite of prevailing high deforestation rates. 2.3.2. Dataset 2.3.2.1. Land use and land cover dataset Multi-annual land use and land cover GIS (Geographic lnforrnation System) layers for 1992 through 2004, produced at GOES for the Landsat path 226 and row 068, were used in this analysis. These layers were generated via standard unsupervised classification of Landsat TM and ETM+ imagery and subsequent manual editing using GIS. Each layer included seven classes of land use (forest, deforestation, secondary regrowth, savannah, cloud, shadow, and water body) (see Table 2.1). Multiple non-forest land use and land cover classes were lumped together to create a forest and non-forest mask. This masking procedure was performed to separate forest only, degraded or not, on each 28 Landsat image. Forest masked images were used to detect selectively logged and burned forests. Table 2.1. Land Use and Land Cover dataset characteristics Dataset Features Format Spatial Period of Projection resolution Analysis Land use Forest, Arc/Info 30m x 30 m 1992 UTM, and land deforestation, grid to Zone 21, cover GIS secondary 2004 Datum and layers regrowth, cerrado, Spheroid clouds, and WGS84 shadows. Moreover, cumulative cloud and shadow layers for the period of analysis also were masked out of all Landsat images, which provided a common area of analysis. However, forested areas affected by smoke, visible on bands 4, 5, and 7, were not masked out. 2.3.2.3. Selective logging dataset Selective logging GIS layers prepared by Matricardi et al. (2005) were used. Matricardi et al. (2005) used semi-automated (texture algorithm) analysis of Landsat band 5 to detect log landings (log storage patios). Subsequently, Matricardi et al. (2005) applied variable buffer zones (180 and 450 meters) around patios to estimate areas affected by selective logging. In addition, selective logged forests showing obvious forest canopy degradation on Landsat images were mapped by digitally circumscribing them on a computer screen. The combination of these techniques allowed the detection of selective logging with 92.9%, 91.2%, and 92.9% of user, producer, and overall accuracy, respectively. 29 Common areas between these two techniques were around 50% without double counting. Areas eventually missed by using automatic analysis were added later by visual interpretation. In this study, the dataset created by Matricardi et al. (2005) was used. This dataset involves multi-annual measurements (1992 to 2002) of selective logging in the study area (path 226 and row 068), located in State of Mato Grosso (Table 2.2). Table 2.2. Selective Logging dataset characteristics Dataset Features Format Spatial Period of Projection resolution Analysis Selectively Binary classes Arc/Info 30m x 30 m 1992 UTM, logged (1 = logging, grid to Zone 21, forest GIS 0 = no data) 2002 Datum and layers Spheroid WGS84 Selective logging layers for two additional years (2003 and 2004) were prepared for this study area using the same methodological approach developed by (Matricardi et al., 2005). Subsequently, selective logging layers were incorporated as part of the land use and land cover change dataset the present analytical effort. 2.3.2.4. Satellite imagery The satellite imagery used in this study was drawn from the archive maintained by the Tropical Rain Forest lnforrnation Center (mpzllwwwtrficmsuedul) at the Global Observatory for Ecosystem Services (GOES), Michigan State University, and by the Brazilian National Institute for 30 Space Research (MH/wwwinpebr). The archive holds Landsat TM and ETM+ images from 1992 to 2004, bands 1 to 5, and 7. The Appendix 8.2 shows further details of the Landsat imagery used in this analysis. 2.3.2.4.1. Radiometric and atmospheric corrections of Landsat imagery Radiometric and atmospheric corrections can significantly improve image quality by reducing atmospheric effects of the absorption by atmospheric gases and the atmospheric scattering processes (Vermote et al., 1997). In this study, radiometric correction was performed to normalize satellite images for factors such as sensor degradation, earth-sun distance variation, incidence angle, view angle, and time of data gathering. This correction involved converting digital number (DN) into radiance and, subsequently, radiance into reflectance using different calibration coefficients provided by the metadata files that accompanied the image files. Coefficients provided by Chamder and Makham (2003) were used for those Landsat TM images in which coefficients were not provided. According to Chamder and Markham (2003), radiometric corrections of Landsat imagery can be performed, first, by converting digital numbers (DN) to radiance: (LMAX/t — LMIN/t L). = Qcalmax )Qcal + LMIN/t. (1) where LA = spectral radiance at the sensor’s aperture in Wl(m2 . sr .p) and Goal = Quantized calibrated pixel value in units of digital numbers (DNs). Then, by converting radiance values to top of atmosphere reflectance using the following equation: 31 2 p? = [ngcar + LMIN}. . (2) where pP = unit less planetary reflectance, LA = spectral radiance at the sensor’s aperture, d = earth-sun distance in astronomical units, ESUN/l = mean solar exoatmospheric irradiances, and Os = solar zenith angle in degrees. The resultant at satellite apparent reflectance was then corrected for atmospheric effects providing at-ground surface reflectance. For converting apparent into surface reflectance the SS (Simulation of the Satellite Signal in the Solar Spectrum) model was used. It required, however, the input of different parameters from the site and sensor as input such as site elevation, sensor altitude, visibility, date of image acquisition, and solar and sensor zenith and azimuth angles. Landsat images are provided with sensor parameters available in a corresponding metadata file for each Landsat image. The site altitude (340 meters) at the center of the Landsat path 226 row 068, and visibility of 20 Kilometers were applied. Based on these parameters, this atmospheric correction model provided linear equation coefficients (Appendix 8.3.) for each Landsat scene. Figure 2.1 shows the procedure for performing these image corrections. 32 Radiometric Digital Radiance TOA Surface correctIon Number Reflectance Reflectance Geometric [ Geometric Registration I correction f Figure 2.1. Stepwise procedure for radiometric and geometric corrections of Landsat imagery Finally, the atmospherically corrected Landsat images were geometrically corrected. The entire procedure for geometric registration is described bellow. 2.3.2.4.2. Normalization of seasonality effect of Landsat imagery Seasonality effects on soil moisture, vegetation phenology, sun angle, etc. occur due to different date of acquisition of remotely sensed data. These effects may affect performance of remote sensing procedures on multi-temporal analysis (Mas, 1999). Therefore, in order to minimize these effects in this study, most images were acquired between May and August. Additionally, normalization of seasonality effects was applied to enable inter-comparison of fourteen Landsat images from different dates in this analysis. Normalization also may minimize atmospheric and other sensor and image variation Elvidge et al. (1995) due to the study area characteristics during the image acquisition period. Normalization was carried out on each Landsat scene. First, a Landsat scene acquired in 2001 was selected as the reference image (a good quality image) after a careful spectral and visual examination of all Landsat scenes included in this study. Then, the brightest and darkest pixels were selected on the reference image and every other image used in the analysis (Elvidge et al., 33 1995). These sampled pixel values consisted of areas covered by undisturbed forests, soil exposure (brightest pixels), and deep water (darkest pixels). A linear regression model was calculated using surface reflectance values from the reference (dependent variable) and every other Landsat image (independent variable), which produced the normalization coefficients (slope and intercept) for each band and Landsat scene. Based on these coefficients (Appendix 8.4), each band and Landsat image was normalized accordingly. 2.3.2.4.3. Geometric correction The Landsat images were previously system-corrected at the TRFIC using the sensor calibration data. Geometric correction accuracy was calculated by comparing common points on system-corrected images to ground collected using GPS from several locations within the study area. Image rectification using 3 to 10 point coordinates and nearest neighbor re-sampling technique was applied. Individual geometric correction was deemed acceptable only if the root-mean- square (RMS) was less than 0.5 pixels. 2.4. Methods This research was based on remote sensing approaches and fieldwork measurements and observations to investigate the processes of forest degradation due to selective logging and forest fire and their temporal changes in the study area in the Mato Grosso state. 2.4.1. Field measurements of forest canopy Field measurements intended to support the assessment of remote sensing approaches and analysis of forest disturbances were conducted from 34 June 20 to July 10, 2004. Different types of selective logging (e.g. ongoing logging and previously logged forests), logged and burned forests, and undisturbed forests were sampled within the study area. Eight transects of 500 meter length were set in these sites. Each transect was appropriately located using Geographic Positioning System (GPS) with x and y coordinates at the start and finish locations (see Appendix 8.5 for further details). Hemispherical photos were acquired for each transect. Canopy openness was measured for both disturbed and undisturbed forests using hemispherical photos (further details are described below). Various types of forest disturbances and intensities were also observed. Hemispherical photos acquired with “fish eye” lens and digital camera (3.2 mega pixels resolution) beneath undisturbed and disturbed forest canopies were used to estimate canopy openness. The photo-shots were taken at 10-meter intervals along each transect. Canopy openness measurement for each individual location was calculated using the Gap Light Analyzer (GLA) software. Fraction canopy openness was estimated using a semi-automated technique because each individual photo requires a threshold empirically defined by the photo interpreter (Appendix 8.6). Subsequently, the canopy fraction was obtained by calculating the difference between 100% and canopy openness (%). In addition, 120 sampling points randomly distributed over forested areas within the study site were visited. Sampling points located too far from the road network were re-located to a closer distance, within a similar forest pattern visually observed on Landsat image. Based on visual evidences of forest fires 35 observed in the field, each sampling point was classified either as burned or not burned forest and appropriately located with x and y coordinates using GPS. 2.4.2. Remote sensing approaches As previously indicated, changes in forest attributes (degradation) are usually too subtle to be accurately assessed using conventional remote sensing approaches and land use classification schemes (Lambin, 1999, Nepstad et al., 1999). Lambin (1999) suggested that biophysical attributes derived from remotely sensed data (e.g. vegetation indices and land surface temperature) at fine spatial resolution should be used to assess changes in forest canopy and identify process of forest degradation throughout a study region. Landscape attributes such as type, size, distribution, and shape, may reveal important spatial components and their interactions that may help to explain process of land cover modification. And, finally, the multi-temporal information can explain processes of land cover changes over time by detecting natural, anthropogenic, seasonal or permanent modifications on the landscape. Analysis forest degradation due to selective logging and forest fire impacts were assessed in this study at local and multi-annual scales, using information from the previously described field measurements, remotely sensed data, and statistical analysis. Moreover, as suggested by Lambin (1999), spectral, spatial, and temporal indicators of forest degradation and regeneration associated with selective logging and forest fire were assessed. Firstly, vegetation indices retrieved from Landsat imagery were tested against canopy cover measurements derived from hemispherical photos acquired in the field, which helped to select 36 an optimum vegetation index, which was used to estimate fractional cover using Landsat imagery. Secondly, time-scale variation of these forest attributes was assessed through multi-temporal analysis of canopy degradation derived from remotely sensed data. Finally, spatial pattern of forest degradation due to selective logging and forest fire and their relationship with other land uses and land cover was analyzed. Further details on remote sensing approaches to assess forest canopy degradation are described as following. 2.4.2.1 . Vegetation lndices Different vegetation indices have been developed and used to better understand the vegetation dynamics in different regions (Qi et al., 1994, Karnieli et al., 2001, Huete et al., 2003). Vegetation lndices (Vls) are mathematical transformations of multiple spectral reflectances employed to estimate the amount of photosynthetically active vegetation at the land surface (Huete et al., 2003) and may be used as indicators of vegetation growth (Wiegand et al., 1991) and forest disturbances (Qi et al., 2002). Vl’s principles are based on the variation of reflected near infrared and red energies by vegetation, and takes advantage of contrasts between soil and vegetation reflectances. Consequently, near infrared and red are the most commonly used spectral bands to calculate vegetation index (Qi et al., 1995). Distance and slope based are the two most important vegetation index developing approaches. Differential between near infrared and red reflectances and the ratio of these two spectral bands are used by the distance and slope 37 based approaches, respectively (Qi et al., 1995, Qi, 2001). Both approaches aim to be more sensitive to the vegetation component, while minimizing external effects due to reflectance of red and near infrared variation at the sensor caused by solar irradiance, atmospheric conditions, canopy background, and vegetation canopy structure and composition (Qi, 2001). MSAVI (Modified Soil Adjusted Vegetation Index), NDVI (Normalized Difference Vegetation Index), and GEMI (Global Environmental Monitoring Index) were tested against canopy cover derived from hemispherical photos to support the selection of the optimum vegetation index. NDVI is one of the earliest and widely used indexes in environmental studies using remotely sensed data. Meanwhile, MSAVI and GEMI are newer approaches aiming to adjust to soil factor and to minimize atmospheric effects, respectively (Qi, 2001). MSAVI is a ratio-based vegetation index developed by (Qi et al., 1994).The basic idea of MSAVI is to provide a variable correction factor “L”. This adjustment factor “L” depends on the level of vegetation cover being observed and on the product of NDVI and WDVI (Weighted Difference Vegetation Index). In this case, the isovegetation lines do not converge to a single point, leading to a circular problem because vegetation covers must be known before calculating the vegetation index, which will generate the vegetation cover. The soil line has arbitrary slope and passes through origin, ranging from —1 to +1. MSAVI: [MR—pm“! (1+L), (3) pN1R+pred+L 38 where leR = reflectance at near infrared band, pred = reflectance at red band, 2 L =I(.0N1R ‘ Pred) * S +1 + Ple + PredI — 8.0 * S * (PNIR ‘ Pred ). (4) where s = 1.2 (slope of the soil line calculated from surface reflectance at non-forested areas in the study site). The NDVI, developed by Tucker (1979), is the most applied index in vegetation studies. NDVI is a ratio-based vegetation index calculated from the difference divided by the sum of two spectral bands yielding a normalized (-1 to +1) difference. NDVI preceded and offered theoretical basis for many other vegetation indices and it still is widely used in remote sensing applications (Qi, 2001). It is defined as follows: NDVI = pm' pm! . (5) pNIR + pred where pNIR = reflectance at near infrared band and pred= reflectance at red band. The GEMI was developed by (Pinty and Verstraete, 1992). It is a distance- based approach and non-linear vegetation index developed to be less sensitive to atmospheric effects. Although GEMI was initially intended to minimize atmospheric effects, it also is more sensitive index to soil background (Qi et al., 1994). 39 770— 0.257;) — (pred — 0.125) (1 — pred) ' where pNIR = reflectance at near infrared band and pred = reflectance at red GEMI = (6) band,and, 2( p2N1R -p2red) + 1.5 pNIR + 0.5 pred 77 : leR + pred + 0.5 (7) Vegetation index applications, however, have been limited by their sensitivity to atmospheric effects, especially on visible bands which are strongly affected by aerosols such as smoke and other types of aerosols (Karnieli et al., 2001, Huete et al., 2003, Moura and Galvao, 2003). Shortwave bands are insensitive to atmospheric effects and are also highly correlated with visible bands under aerosol-free atmospheric conditions. Therefore, shortwave bands have been favored as an alternative approach to replace the most sensitive bands when atmospheric effects thwart multi-temporal analysis (Karnieli et al., 2001, Moura and Galvéo, 2003). Based on these characteristics of the shortwave bands, Karnieli et al.(2001) tested four modified vegetation indices (NDVI, Soil-Adjusted Vegetation Index — SAVI; Atmospheric Resistant Vegetation Index - ARVI; Soil-Adjusted Atmospheric Resistant Vegetation Index - SARVI) for a study site in the Amazon State of Mato Grosso, Brazil. Karnieli and his colleagues developed a modified NDVI, named the Aerosol Free Vegetation Index (AFRI), which uses an empirical relationship to estimate red band reflectance from shortwave infrared band at 2.1 pm. Equation 8 defines this vegetation index: 40 pNIR — 05,0st (8) AFR12 1 = . I leR 'I- O'SPSWIR where IONIR= reflectance at near infrared and pom: reflectance at 2.1 pm (Shortwave infrared). This vegetation index has proven to be useful to estimate biomass burned in the presence of smoke and other atmospheric pollutants. However, AFRI may not produce good results if atmospheric particles are of equal or larger sizes than the wavelength at 2.1 pm (Karnieli et al. 2001). 2.4.2.2. Modified Vegetation Index approaches The acquisition of remotely sensed data affected by smoke and other aerosols was unavoidable due to the prevailing land use practices in the study region. Consequently, I had to assess performance of various vegetation indices to estimate forest canopy degradation under adverse atmospheric conditions. I tested four vegetation indices (AFRI, NDVI, MSAVI, and GEMI) and the Green Vegetation (GV) derived from SMA to estimate fractional coverage in the study site under smoke conditions. Additionally, I also tested a modified GEMI and MSAVI using the same empirical linear relationship estimated by Karnieli et al.(2001) to predict red band reflectance based on shortwave infrared at 2.1 pm. The equations 9 and 10 define the GEMI“ model. 770- 0.2527) — (0.5pswm —0.125) GEMI = 2'1 (1 — 0.5pSW1R) (9) where pNIR = reflectance at near infrared band and pswm = reflectance at 41 shortwave infrared band (2.1 pm), and, _ 2(p2NIR - 0.5p2SWIR)+1.5leR + 0.5(0.5pSll'lR) _ leR + OSPSWIR + 0.5 ' (10) The MSAVI using wavelength at 2.1 pm was named MSAVIaf (Modified Soil-Adjusted Vegetation Index aerosol resistant). The equations ‘1 1’ and ‘12’ describe the MSAVIaf model. 1R — 0.5 WlR MSAVIaf= pN ’05 (1+L), (11) prime + 0.5pSWIR + L where leR = reflectance at near infrared band, pswm = reflectance at Shortwave infrared band (2.1 pm). L = [(PNIR -0-5DSWIR)* S + 1 + PNIR + 0-5PSWIR12 -8-0 * 5* (PNIR -0-5PSWIR) .(12) where s = 1.2 (slope of the soil line calculated from surface reflectance at deforestation areas in the study site). 2.4.2.3. Spectral Mixture Analysis Multi-spectral categories may be represented by each pixel, and mixing proportions (class fractions or abundances) change from pixel to pixel. Furthermore, real world scenes always have spatial details with smaller dimension than any Ground Instantaneous Field of View (GIFOV) which ultimately represent the spatial resolution of a given sensor or satellite image. Moreover, spatial mixing can be also derived from a image resampling process (Rencz, 1999). 42 The number of spectral bands available in the dataset plus 1 defines the total of possible end members. In practice, the number of end members ranges from three to seven, depending on the number of bands of the data set and the spectral variability of the scene components (Rencz, 1999). The selected endmembers are used to solve the following mixture modeling equation: N N DNb =i§1FiDNib +Eb or DNb = ERR“, + ab, (13) where DN,> = intensity of a given pixel in bandpass ‘b’, DN,- = intensity of image endmember ‘r’ at wavelength ‘b’, Rib = reflectance of end member ‘i’ in bandpass ‘b’ (if an image is calibrated to reflectance, Rib must be used instead), N = number of endmembers, and ab = error of the fit for bandpass ‘b’. A second equation may be used to constrain the sum of fractions to 1: Fi = 1.0 , (14) 'M2 I I where F,-= fractional abundance of endmember ‘i’ Since spectral endmembers may be the result of mixing with different materials, fractional abundance of endmember ‘I’ may be less than 0 and greater than 1, although the overall fraction will be 1. It indicates that two materials may be combined, which will result a negative or greater than 1 fraction. It does not necessarily mean that there are method errors (Rencz, 1999). 43 2.4.2.3.1 . Endmember selection Spectral mixture analysis approach relies on endmember selection and, therefore, accuracy depends on their accurate selection of endmembers. Spectral signatures or spectral endmembers correspond to the physical endmembers that show maximum abundance. Spectral endmember identification for each piece of terrain is the first stage Rencz (1999) and main objective in mixture modeling (Adams et al., 1995, Bateson and Curtiss, 1996, Rencz, 1999). Theoretically, the data dimension and constraints of the mixture inversion define the number of end members. Consequently, the number of spectral bands in the dataset plus 1 defines the total of possible end members. However, empirically, the number of end members ranges from three to seven, depending on the number of bands of the data set and the spectral variability of the scene components (Rencz, 1999). As previously indicated, the available dataset (spatial and spectral resolution, bands, etc.) and classes of surface materials (soil, shade, green vegetation, non-photosynthetic vegetation, etc.) of a given area affect the definition of endmembers in SMA. Thus, image endmembers can be identified based on some criteria (spectral library acquired from a specific site) or using other techniques (Rencz, 1999). The end members are idealized pure signature for a class of a particular location and are the extreme pixels of the scatter plot when spectral libraries are used. Endmembers do not actually exist in the dataset, but their convex hull will enclose all data in the scattered plot. Endmembers represent 100% pure pixels in 44 their respective classes. For example, the shade endmember is a result of both shade and shading highly affected by the local topography, vegetation, and seasonal and daily solar variation. Therefore, shade endmember may compose with other endmembers in a given satellite scene and proportionally vary with these illumination characteristics (Rencz, 1999). The Pixel Purity Index (PPI) also is presented as an option to select end members. This technique was based upon the principle that spectral signature of a specific material is ‘pure’ (not compounded) Adams et al. (1995) and, therefore, PPI was designed to identify the most spectrally extreme, different, or ‘pure’ pixels, which commonly correspond to mixing endmembers (Adams et al., 1995, Boardman et al., 1995). The PPI is calculated by repeatedly projecting n- dimensional scatterplots onto a random unit vector. To find the PPI value, the extreme pixels in each projection are identified and their frequencies as extreme are determined. A PPI image is generated accordingly with the resultant histogram of the frequency of each pixel value as extreme, and thus making evident the purest pixels with extremity-scores (Boardman et al., 1995). For the present study, a four-endmember mixing model was constructed to generate fraction images of shade, soil, non-photosynthetic vegetation, and green vegetation. The end-member candidates were selected by using the previously describe PPI technique. Six image subsets of 502 x 502 pixels representing the variety of land use and land cover types within the study site were used as input for the PPI algorithm for each year of analysis. Purest pixel candidates were identified based on the PPI results and located on the original 45 Landsat imagery within the study area. A final visual and spectral examination of spectral shape and image context was conducted accordingly to select the final endmembers for the SMA. 2.4.2.4. Fractional cover Fractional cover or green fractional percentage can be estimated by using a simple linear mixture model (LMM) and two spectral end members (plant canopy and bare soil) as following (Maas, 2000, Qi et al., 2000): fc- VI—Vlopen *100 (15) — VIcanopy — VIopen where fc = green fractional percentage, VI = vegetation index value, VI canopy = vegetation index value of the tree green canopy, and VI open = vegetation index value of senescent open areas (Figure 2.2). Figure 6 shows the procedure to calculate fractional cover. [ Surface reflectance H Vegetation index ] l t [ End member selection H Fractional cover (%) ] Figure 2.2. Procedure for calculating fractional cover Forest canopy disturbances and regeneration were estimated using fractional cover derived from the discussed vegetation indices previously (NDVI, MSAVI, GEMI, AFRI, MSAVIaf, and GEMI“, and GV), all retrieved from remotely sensed data. The performance of each vegetation index was observed based on the statistical results of Pearson correlations among the vegetation indices 46 retrieved from a Landsat image acquired in August 6, 2003, under clear sky and in the presence of smoke for a variety of land cover types. The optimum vegetation index was defined based on its performance under smoke conditions and on the results of the empirical linear relationship between fractional cover retrieved from a Landsat image acquired in June 21, 2004 and fractional cover calculated from hemispherical photos also acquired during June, 2004, for different sites within the study area. Forest canopy degradation of selectively logged and burned forests, selectively logged only, and undisturbed forests were also compared. 2.4.2.5. Burned forest detection Burned forests were detected using non-photosynthetic vegetation fraction images derived from the linear mixing model. This technique was first developed by Cochrane and Souza Jr. (1998) to detect selective logging sites and burned forests using Spot images in a case study in Para, Brazil. I improved this approach to a fully automated technique to detect and map burned forests using non-photosynthetic vegetation fraction image derived from Landsat imagery. Therefore, burned forests were detected and mapped in the study area from 1992 to 2004. Additional details of this remote sensing approach for detecting burned forests are described bellow. 2.4.2.5.1. Burned forest detection approach This approach consisted in: 1) masking Landsat images in forest and non- forest, and 2) unmixing multispectral images using shade, green vegetation, and non-photosynthetic vegetation (NPV) endmembers. In this case, multispectral 47 images were unmixed based on Adams et al (1995) who observed that fraction images could be generated considering particular endmembers (spectral pure signature) that represent specific components such as green vegetation, soil, non-photosynthetic vegetation, and shade. The Landsat imagery was processed as described on Figure 2.3. Landsat Image [(Surface ReflectancJ [ LULC Layer V Masking out non-forest Forest and ’non-forest binary classification l Lorest, NPV, Shade E ndmember Selection T’T L__J [NPV FractIon Image (289 P'Xels) 7 Binary classification NPV>0.12=1, 0else Low paSSI filter (5 x 5 pixels) Masking out non-forest l Eliminate clumps ] .83 , Pixel clumping L (4 pixels) J [Burned Forest Map] Figure 2.3. Flow diagram for burned forest automated detection technique The NPV fraction images were classified following a binary labeling (burned forests = 1 if NPV value was greater or equal 0.12; and unburned forests = 0 othenivise). Subsequently, these classified images (burned and non-bumed forests) were 4 pixels clumped using the clump algorithm from Erdas Image 48 software. Clumps lesser than or equal 289 pixels were eliminated to remove small pixel clusters (noise) of misclassified unburned forests. Finally, a low pass filter was applied on clump eliminated images to smooth out limits of the detected burned forests. 2.4.3. Forest canopy degradation assessment Forest canopy degradation by selective logging, forest fire, logging and fire combined and forest regeneration following each of these forest disturbances in the study area was assessed using multiple regression analysis. Multiple regression analysis is useful technique to estimate partial effects of the independent variable by controlling many other factors that simultaneously affect the dependent variable (Wooldridge, 2000). By using the pixel as the unit of observation and based on (Wooldridge, 2000), the multiple linear regression model for green fractional percentage was defined as: FC% = ,60 + fl1x1+ ,Bzxz +...+,624x24 + u , (16) where FC% is the observed continuous variable (green fractional percentage derived from remotely sensed data), and ,80 is the intercept or constant, ,6] is the parameter associated with x1 (independent variable 1), ,62 is the parameter associated with x2 (independent variable 2) and so on. The variable u is the error term, which contains factors other than the independent variables included in this model that affect FC%. The vector of independent variables (x) tested are the following: 49 x1 = Deforestation areas x2 = Newly logged forests x3 = Old logged forest detectable x4 = Old logged forest non-detectable x5 = Newly logged and burned forests x5 = Newly burned forests x7 = Old logged and burned forest detectable x8 = Old logged and burned forest non-detectable x9 = Old burned forest detectable x10 = Old burned forest non-detectable X11= Year Of1993 X12 = Year Of1994 x13 = Year of 1995 x14 = Year of 1996 x15 = Year of 1997 x16 = Year of 1998 x17 = Year of 1999 x13 = Year of 2000 x19 = Year of 2001 x20 = Year of 2002 x21 = Year of 2003 X22 = Year Of 2004 x23: Longitude or x location (kilometer) x24 = Latitude or y location (kilometer) OOOOOOOOOOOOOOOOOOOOOOOO Note: Undisturbed forest and the year of 1992 were used as omitted variables for the land use classes and annual changes, respectively. By using this multiple regression analysis, I was able to measure the effect of each land use or year of analysis on forest canopy cover in the study area, holding the other independent variables fixed. 2.4.3.1 . Testing Hypotheses Based on field observations, I expected that impacts by any anthropogenic activities should have effects on forest canopy coverage. Therefore, any particular land use and land cover type should affect (increase or decrease) values of fractional coverage when compared to undisturbed forest. I also expected that effects of non-controlled seasonal and natural variations (e.g. El 50 Nino effects, extreme droughts, etc.) would impact values of fractional coverage. Finally, I expected that values of fractional coverage could be affected by uncontrolled spatial variability of natural forests (e.g. response of vegetation phenology to precipitation) and human activities in the study area. I hypothesized about each value of twenty four slope coefficients ( ,6, , 62, ,624), once the effect of other coefficients had been account for, and used statistical inferences to test these hypotheses as following: Ho: Null hypothesis: Land use and land cover change variables ( ,6, to 6,0): ,6] = 0: Deforestation has no effect on fractional coverage. ,62 = 0: Newly logged forest has no effect on fractional coverage. ,63 = 0: Old logged forest detectable has no effect on fractional coverage. ,64 = 0: Old logged forest non-detectable has no effect on fractional coverage. ,65 = 0: Newly logged and burned forest has no effect on fractional coverage. ,66 = 0: Newly burned forest has no effect on fractional coverage. ,67 = 0: Old logged and burned detectable forest has no effect on fractional coverage. ,68 = 0: Old logged and burned non-detectable forest has no effect on fractional coverage. ,69 = 0: Old burned forest detectable has no effect on fractional coverage. .310 = 0: Old burned forest non-detectable has no effect on fractional coverage. Temporal variables (,6l1 to ,822 ): ,8”: 0: Non-controlled seasonal or temporal variations for 1993 have no effect on fractional coverage. ,612= 0: Non-controlled seasonal or temporal variations for 1994 have no effect on fractional coverage. ,613 = 0: Non-controlled seasonal or temporal variations for 1995 have no effect on fractional coverage. fl” = 0: Non-controlled seasonal or temporal variations for 1996 have no effect on fractional coverage. ,615 = 0: Non-controlled seasonal or temporal variations for 1997 have no effect on fractional coverage. 51 H1: .316: 0: Non-controlled seasonal or temporal variations for 1998 have no effect on fractional coverage. ,6” = 0: Non-controlled seasonal or temporal variations for 1999 have no effect on fractional coverage. ,6”; = 0: Non-controlled seasonal or temporal variations for 2000 have no effect on fractional coverage. [319: 0: Non-controlled seasonal or temporal variations for 2001 have no effect on fractional coverage. ,820= 0: Non—controlled seasonal or temporal variations for 2002 have no effect on fractional coverage. 621: 0: Non-controlled seasonal or temporal variations for 2003 have no effect on fractional coverage. ,322= 0: Non-controlled seasonal or temporal variations for 2004 have no effect on fractional coverage. Spatial variables ( ,623 to ,624): ,623 = 0: Anthropogenic and natural spatial variations over longitude (x) direction have no effect on fractional coverage. ,624= 0: Anthropogenic and natural spatial variations over latitude (y) direction have no effect on fractional coverage. Alternative hypothesis: Land use and land cover change variables ( ,6] to ,610 ): ,6] ¢ 0: Deforestation has effect on fractional coverage. ,62 t6 0: Newly logged forest has effect on fractional coverage. ,63 at 0: Old logged forest detectable has effect on fractional coverage. ,64 ¢ 0: Old logged forest non-detectable has effect on fractional coverage. ,65 ¢ 0: Newly logged and burned forest has effect on fractional coverage. ,66 at 0: Newly burned forest has effect on fractional coverage. fl7 ¢ 0: Old logged and burned detectable forest has effect on fractional coverage. ,68 ¢ 0: Old logged and burned non-detectable forest has effect on fractional coverage. fig at 0: Old burned forest detectable has effect on fractional coverage. filo ¢ 0: Old burned forest non-detectable has effect on fractional coverage. Temporal variables (,611 to ,622): fl11¢ 0: Non-controlled seasonal and temporal variations for 1993 have effect on fractional coverage. ,612 at 0: Non-controlled seasonal and temporal variations for 1994 have effect on fractional coverage. 52 613150: 614560: 615% 0: 616;! 0: 61759 0: 613:5 0: ,619¢0: flzoaéo: 1321’”): fl22¢ OI Non-controlled seasonal and temporal variations for 1995 have effect on fractional coverage. Non-controlled seasonal and temporal variations for 1996 have effect on fractional coverage. Non-controlled seasonal and temporal variations for 1997 have effect on fractional coverage. Non-controlled seasonal and temporal variations for 1998 have effect on fractional coverage. Non-controlled seasonal and temporal variations for 1999 have effect on fractional coverage. Non-controlled seasonal and temporal variations for 2000 have effect on fractional coverage. Non-controlled seasonal and temporal variations for 2001 have effect on fractional coverage. Non-controlled seasonal and temporal variations for 2002 have effect on fractional coverage. Non-controlled seasonal and temporal variations for 2003 have effect on fractional coverage. Non-controlled seasonal and temporal variations for 2004 have effect on fractional coverage. Spatial variables ( ,623 to ,624): ,823 at 0: Anthropogenic and natural spatial variations over longitude (x) direction have effect on fractional coverage. 624:6 0: Anthropogenic and natural spatial variations over latitude (y) direction have effect on fractional coverage. 2.4.3.2. Data sampling Spatial autocorrelation can substantially increase the error term in the at al. 2007) regression model. Anselin (2002) suggested that these effects of spatial autocorrelation can be minimized by systematically sampling the dataset. Therefore, in this analysis, a vector file of 3 km x 3 km sample points distributed over the study area was generated. 8y sampling each point at a fixed distance from the others, potential contagion between neighboring cells is isolated (Arima and the error term in the regression model due to spatial 53 autocorrelation in the dataset is reduced (Anselin 2002, Arima 2007). The study area was systematically sampled by acquiring unique values for the dependent and independent variables at each sampling point location, all derived from remotely sensed data. In addition, each cell location was identified by its longitude (x) and latitude (y) locations in the study area. The cell x and y locations were used in the regression model as an additional set of independent variables. This procedure helps to identify spatial trends and also to mitigate potential effects of spatial autocorrelation in the data population (Chomitz and Gray, 1996). 2.5. Results and Discussions 2.5.1. Relationships among various Vegetation lndices In this analysis, the relationship among NDVI, MSAVI, GEMI, AFRI, MSAVIaf, GEMI“, and GV retrieved from a Landsat image acquired in August 6, 2003 were tested under smoke and smoke free atmospheric conditions. Table 2.3 shows the relationship among these vegetation indices under clear sky for the study area. This correlation matrix demonstrates high correlation (r > 0.90) among all vegetation indices under clear sky atmospheric condition. Although a perfect correlation (r= 1) was not observed among different vegetation indices, as observed by (Karnieli et al., 2001), these research results showed high correlations between NDVI and AFRI (r = 0.99), GEMI and GEMI2_1(r= 0.98), and MSAVI and MSAVIaf (r = 0.98), which are the modified vegetation indices that use an empirical linear relationship observed by (Karnieli et al., 2001) to predict 54 red band reflectance from shortwave infrared at 2.1. High correlation (r2 0.98) also was observed between GV and GEMI, CV and GEM|2.1, GV and MSAVI, and GV and MSAVIaf. Table 2.3. Correlation matrix among various vegetation indices under smoke-free atmospheric condition for the study site Vegetation Index NDVI AFRI GEMI GEMIM MSAVI MSAVIg GV NDVI 1 AFRI 0.99 1 GEMI 0.97 0.96 1 GEMI“ 0.93 0.94 0.98 1 MSAVI 0.96 0.94 0.98 0.96 1 MSAVIaf 0.93 0.94 0.97 0.97 0.98 1 GV 0.95 0.96 0.99 0.99 0.98 0.98 1 Correlation is significant at the 0.01 level (1-tailed). N= 2000. Bold values represent special interest in this analysis. Vegetation indices, however, are very sensitive to atmospheric conditions, especially on visible bands, which can strongly affect their results (Karnieli et al., 2001, Huete et al., 2003, Moura and Galvao, 2003). In this study, sensitivity of each vegetation index to presence of aerosol was tested. Table 2.4 demonstrates the performance of various vegetation indices under smoke condition in the study site. In this case, high correlation among aerosols resistant vegetation indices (AF RI, GEMI”, MSAVIaf, GV) and those more sensitive vegetation indices (NDVI, GEMI, MSAVI) to atmospheric effects indicated low performance in penetrating through the aerosols and depicting the vegetation cover under heavy smoke atmospheric condition. Therefore, low correlation between them was desired. Lowest correlation was observed for GEMI2,1and NDVI (r= 0.87), 55 MSAVIaf and NDVI (r= 0.87), and AFRI and NDVI (R=0.89). Relatively low correlation also was observed between MSAVIaf and MSAVI (r= 0.90). Table 2.4. Correlation matrix among various vegetation indices for areas in the presence of heavy smoke in the study site. Vegetation Index NDVI AFRI GEMI GEMI“ MSAVI MSAVlg GV NDVI 1 AFRI 0.89 1 GEMI 0.95 0.84 1 GEM|2,1 0.87 0.88 0.96 1 MSAVI 0.96 0.78 0.98 0.90 1 MSAVI,“ 0.87 0.87 0.94 0.97 0.90 1 GV 0.93 0.88 0.99 0.99 0.95 0.97 1 Pearson correlation is significant at the 0.01 level (1-tailed). N: 2000. Bold values represent special interest in this analysis. The Appendix 8.7 demonstrates MSAVI and MSAVIaf performances under smoke condition. Although GV derived from SMA was highly correlated to GEMI2_1 (r= 0.99) and MSAVIaf (r= 0.97), it was also highly correlated (r> 0.90) with those more sensitive vegetation indices (NDVI, GEMI, and MSAVI) to atmospheric influences, which indicated that GV was more sensitive than AFRI and MSAVIaf to the presence of heavy smoke in this study area. Low correlation (r < 0.90) also was observed between AFRI and all other vegetation indices, which may indicate that each index has a different response to atmospheric effects when compared to AFRI. 2.5.2. Optimum Vegetation Index In addition to the previously discussed relationships among various vegetation indices, empirical linear relationship between fractional coverage values derived from each vegetation index and from forest canopy coverage 56 calculated using hemispherical photos acquired in the study site. A total of 423 hemispherical photos were used to calculate 47-canopy fraction points on the ground, estimated based on the average of 9 hemispherical photos each point. The hemispherical photos were located over the study area using GPS. Likewise, 47-canopy fraction points were calculated from NDVI, MSAVI, GEMI, GV, AFRI, GEMI“, and MSAVIaf fractional coverage derived from Landsat image, based on the average of a group of 9 pixels (window 3 x 3) each point. The table 2.5 shows the statistical results of the linear relationship between each fractional coverage image derived from various vegetation indices and canopy coverage estimated using hemispherical photos acquired in the study area. Table 2.5. Empirical linear relationship between various vegetation indices and forest canopy coverage based on field measurements in the study site Vegetation R-Square Prob > F F(1, 45) Index MSAVI 0.84 0.000 236.83 GEMI 0.80 0.000 182.21 NDVI 0.67 0.000 92.26 MSAVI,“ 0.81 0.000 191.90 GEMI“ 0.78 0.000 155.79 AFRI 0.60 0.000 68.25 GV 0.76 0.000 144.24 N= 47. Bold values represent special interest in this analysis MSAVI showed the highest R2 (0.84) indicating that 84% of the sample variation in fractional coverage derived from ground measurements can be explained by fractional coverage derived from MSAVI model. MSAVIaf and GEMI showed slightly lower R2 (0.81 and 0.80, respectivelY). and NDVI, GEMI2_1,AFRI, 57 and GV showed R2 lower than 0.80. Indeed, a good performance by MSAVI had been observed for this study region by (Wang et al., 2005). In that study, the authors selected MSAVI as the optimum vegetation index to estimate fractional coverage derived from ETM+ image using lkonos image as a ground truth for validation. Any abnormal atmospheric condition, however, was not reported by (Wang et al., 2005). AFRI, GEM12_1, and MSAVlafpresented great potential to estimate fractional coverage from Landsat imagery for this study area, if considered that these indices fitted fairly well the fractional coverage derived from hemispherical photos acquired in the field and showed good capability to penetrate the atmosphere when aerosols is present. Based on these previously discussed limitation and potential of various vegetation indices, I selected MSAVIaf as the optimum vegetation index for this study site given its good performance under clear sky for the study area, high correlation with its non-modified version (MSAVI), slightly better fitting to field measurements compared to other modified vegetation indices, and, most importantly, its good performance under smoke conditions. 2.5.3. Accuracy assessment of burned forest detection technique The accuracy assessment was conducted by comparing binary classification (1 = burned forest, 0 = non-burned forest) from the burned forest map derived from Landsat TM5 image with 120 randomly distributed points in forested area, checked during the field observation within the study site. Both remotely sensed and fieldwork data were acquired in June 2004. Kappa statistics 58 and standard Producer’s, Users, and overall accuracies of this burned forest detection technique are presented in Table 2.6. Table 2.6. Accuracy assessment results of detecting burned forests using non- photosynthetic vegetation (N PV) fraction image derived from Spectral Mixture Analysis (SMA) for the study area in 2004. Land Use Reference Classified Number Accuracy Points (*) points Correct Producer User Burned forests 79 80 77 non-burned forests 41 40 38 92.7% 95.0% Overall accuracy = 96.0% Overall Kapa Statistic = 0.91 * 120 randomly distributed sampling points within forested area The commission and omission errors were 7.3% and 5%, respectively. The accuracy assessment results demonstrated that this remote sensing approach could correctly classify 96% of burned forest if the source of error (commission and omission errors) is not accounted for. Appendix 8.8 shows a sample of burned forests mapped using this remote sensing approach. 2.5.4. Multi-annual land use and land cover change Based on these research results, it was observed that deforestation increased from approximately 3400 km2 by 1992 to 8500 km2 by 2004, an average increase of 426 km2 yr" (:1: 202 kmz, standard deviation). The greatest deforestation increase, however, was observed between 2003 and 2004, at 980 km2. The total disturbed forests within the study region (path 226 and row 068) increased from 5.4% to 40.1%, by 1992 and by 2004, respectively. These forest disturbances correspond to an annual increase of 1,270 km2 yr’1 (i482 km2) of forests selectively logged and/or burned. Only 30.5% of the study area was 59 considered undisturbed forest by 2004. Table 2.7 shows the annual land use and land cover change over the study site. Table 2.7. Cumulative deforestation and undisturbed and disturbed forests in the study area from 1992 to 2004. Logged & Undisturbed Logged Burned forest Year forest forest only Burned forest only Deforestation (km2) (km2) (km2) (km2) (km2) 1992 24,1315 1,120.9 45.1 395.7 3,403.6 1993 22,4721 2,243.7 56.1 424.5 3,900.3 1994 21 ,441 .7 2,911.7 70.6 426.5 4,246.4 1995 20,3781 3,441.9 144.9 468.6 4,663.3 1996 19,2849 4,142.8 176.5 455.8 5,036.8 1997 17,9098 5,089.3 181.3 495.6 5,420.8 1998 16,5548 6,069.1 246.1 493.3 5,733.4 1999 ' 14,1606 7,522.0 486.9 705.8 6,221.4 2000 12,5159 7,560.2 1,491.7 1,171.3 6,357.7 2001 11,1287 8,553.0 1,508.5 1,062.6 6,844.0 2002 10,4222 8,975.8 1,553.2 1,028.1 7,117.5 2003 9,606.4 9,440.2 1,570.0 939.2 7,541.0 2004 8,894.1 9,274.7 1,549.3 857.8 8,520.7 A mask of 972 km2 of the cumulative clouds and shadows was applied. Approximately 36.3 km2 of water bodies that were annually detected on all scenes were not included. In this given period, selective logging alone was responsible for disturbing a large extent of natural forests, equivalent to more than 31 % of this study area by 2004. An additional of 5.5% and 2.9% of the study site forest was disturbed by selective logging and fire combined and forest fire only, respectively. By 2002, the total area of disturbed forests already had surpassed by more than 1,100 km2 the total area of undisturbed forest in this study site. Figure 2.4 shows the annual change of undisturbed into disturbed forests and the forest conversion into agricultural lands (deforestation) in the study region. 60 30.000 25,000 20,000 ' , 15.000 - Area (km2) 10,000 « 5,000 , 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 Year I; Undisturbed forest I Disturbed forest I Deforestatiofl Figure 2.4. Land use and land cover change from 1992 to 2004 in the study site These results also show that more than 10,000 km2 of remnant logged and burned forests had recovered sufficiently to be undetected (non-persistent) by 2004 using Landsat imagery. Appendix 8.9 shows annual changes of persistent and not persistent disturbed forests by selective logging and forest fire in this study area. New areas of selective logging only increased around of 904 km2 yr" (i354 km2) from 1992 to 2004 in this study area. An annual average of 422 km2 yr" (i440 km2) of logged forests were burned, and around of 426 (1:202 km2) and 102 km2 yr" (i152 km2) of undisturbed forests were deforested and burned, respectively. The greatest annual increase (around of 1728 km2) of selective logging only occurred in 1999. Immediately following this year, it was observed a 61 substantial increase (around of 1370 km2) of newly burned forests over logged forest by 2000. Table 2.8 shows the annual increase of selectively logged only, selectively logged and burned forests combined, and burned forest only, from 1992 to 2004 in the study site. Table 2.8. Annual increase of selectively logged forest, burned and logged forests combined, and burned forest only, from 1992 to 2004 in the study area. Annual Increase (km2) Logged Burned & Burned & Burned Deforestation Year forest newly logged Old Logged forest hma mma 1992 1,120.9 45.1 - 395.7 1993 1,158.1 14.0 0.8 88.7 496.7 1994 708.9 11.1 1.6 22.5 346.0 1995 634.2 42.0 25.9 70.2 416.9 1996 785.2 17.2 23.1 23.6 373.5 1997 1,022.3 11.6 0.5 66.9 384.0 1998 1,072.0 41.0 11.9 38.9 312.6 1999 1,727.9 111.0 145.4 249.4 488.0 2000 873.1 296.8 721.0 539.5 136.3 2001 1,116.6 64.4 6.3 10.5 486.3 2002 540.5 34.9 14.5 50.2 273.5 2003 834.8 22.2 37.2 33.9 423.5 2004 375.7 10.2 63.2 24.1 979.7 The analysis of the land use dynamics over the study site showed that previously logged and burned sites could be revisited by loggers and recurrent forest fires, respectively. Revisited logging accounted for more than 3300 km2 by 2004, an average of 276 km2 yr" (1197 km?) from 1992 to 2004. Recurrent fires accounted for 866 kmz, an average of 72 km2 yr" (:I:50 km2) in the same interval. It was also observed that more than 1756 km2 of selectively logged forests and an additional 368 km2 of burned forests had been deforested by 2004. 62 Table 2.9. Multi-annual land use dynamics in the study site from 1992 to 2004 Revisited Recurrent Disturbed forests deforested by 2004 Year logging fire 8y logging By logging By Fire only (km2) (km2) only (km2) & Fire (km ) (km2) 1992 372.9 25.1 211.5 1993 0 0 337.2 1.4 46.4 1994 32 61.8 307.2 0.8 9.2 1995 51.4 54.95 191.2 15.6 44.5 1996 101.6 37.2 154.8 3.3 12.8 1997 148.9 82.58 135.9 3.0 19.2 1998 319.3 74.78 175.5 10.1 20.6 1999 431.7 181.52 137.4 16.2 68.1 2000 491.6 92.43 85.6 44.5 134.9 2001 394.5 23.34 70.4 2.2 2.6 2002 455.3 73.71 - - - 2003 537.3 142.09 62.4 1.9 10.2 2004 350.1 41.63 - - - Total 3,313.7 866.0 1,657.7 99.0 368.3 2.5.5. Assessment of forest canopy cover impacts In this analysis, I was primarily concerned in assessing impacts of temporal and land use and land cover changes on forest canopy cover. Therefore, multiple regression analysis was applied to measure partial effect of each of factor of interest, holding fixed all other factors affecting the fractional coverage. The results of this analysis showed that the multiple regression equation (16) can significantly explain 63.07% of the dependent variable (fractional coverage) at a = 0.01 (probability of 99%). Additionally, the hypothesis testing for measuring partial effect of each land use and land cover on fractional coverage was conducted as following. I could not reject the Null Hypothesis for the old burned forest non- detectable, year of 2004, and longitude (x) direction variables. More specifically, the fractional coverage values for old burned forest non—detectable and 63 undisturbed forest (the land use omitted variable) derived from Landsat imagery were not significantly different, at q = 0.01. Similarly, fractional coverage values for the years of 2004 and 1992 (the temporal omitted variable) also were not significantly different, at a = 0.01. Fractional coverage values did not significantly change according to longitude (x) location, at a = 0.01, which means that there is no spatial trend in east-west direction. I could reject, however, the null hypotheses for all other tested coefficients and accepted the alternative hypotheses that there were statistically significant differences between fractional coverage values of each coefficient and its corresponding omitted variable (undisturbed forest or year of 1992). Based on these accepted alternative hypotheses, partial effect of each factor of interest was assessed. Water body significantly decreased 61.9% (:I: 3.6), at a = 0.01, of fractional coverage values compared to fractional coverage for undisturbed forests (the land use omitted variable). Indeed, vegetation indices are very low for water bodies due to low reflectance on infrared wavelengths (Wang et al., 2004). The effects of deforestation were the second greatest contributor for forest canopy loss, decreasing 53.5% (:I: 0.8) of forest canopy values, at a = 0.01, compared to fractional coverage values for undisturbed forests, holding all other factors (independent variable) fixed. Indeed, deforestation implies in cutting down, damaging, and burning forests, converting natural forests into other land use type Skole and Tucker (1993) and FRA (2005) where forest canopy cover is drastically reduced (FRA, 2005). 64 In terms of forest uses, newly logged forest only significantly decreased 5.0% (:I: 0.8), at q = 0.01, forest canopy in the study area compared to fractional coverage for undisturbed forests. On the other hand, newly burned forest significantly decreased 28.9% (:I: 2.0), at d = 0.01, forest canopy and, when combined selective logging and forest fires, decreased 35.6% (1 2.1) forest canopy compared to fractional coverage for undisturbed forests. Figure 2.5 shows the estimated losses and gains of canopy coverage based on the multiple regression model of fractional coverage for various forest uses classified in the study site using Landsat imagery acquired from 1992 to 2004. The alternative hypothesis that old (previously) logged forests detectable using remotely sensed data has effect on fractional coverage also was accepted. In this case, old logged forest significantly contributed to decrease only 1.6% (i 0.7), at a = 0.01, of fractional coverage values compared to those for undisturbed forest. On the other hand, old logged forests that recovered sufficiently to become undetectable using Landsat images, accounted for a significant increase of 3.1 (:I: 0.5), at a = 0.01, of fractional coverage values, compared to undisturbed forests. These results indicate that strong forest regeneration occurred and contributed to increase vegetation greenness as well as fractional coverage values, surpassing even fractional coverage value for undisturbed forests in this study area. Old burned forests detectable using remotely sensed data showed a significant decrease of 12.6% (:I: 1.5), at a = 0.01, of fractional coverage values and, when not detectable, showed no significant change in canopy cover. In this 65 last case, the null hypothesis that old burned forest has no effect on fractional coverage could not be rejected. And again, old areas of detectable selective logging and forest fire combined showed significant decrease of 25.6% (1 2.0), at d = 0.01, of fractional coverage values, and even when not detectable, still showed significant decrease of 4.7% (:t 1.1), at a = 0.01, of fractional coverage values compared to undisturbed forests. Forest canopy change (%) j {i Newly” logged 7' Dad logged forestidetectable A "7 7 ‘ 1 l Old logged forest non-detectable I Newly logged & bLmed forest 1 I I Newly buried l Old buned forest detectable l l Old bumed forest non-detectable Old logged & bu'ned forest detectable II Old logged 8r buned forest non-detectable Figure 2.5. Partial effects of various forest uses on fractional coverage values in the study area estimated using linear multi-regression model and multi-annual remotely sensed derived dataset As previously stated, in terms of temporal change, all years from 1993 to 2003 showed significant change of fractional coverage values at a = 0.01 compared to 1992 (omitted variable) and the alternative hypotheses that non- controlled seasonal and temporal variations significantly affected fractional 66 coverage values. The greatest annual losses of fractional coverage, 8.8% (:I: 0.7) and 8.4% (:I: 0.7), were observed for 1993 and 1999, respectively. Based on these results, the average around of 3.6% and 6.4% of forest canopy losses were observed for 1994-1998 and for 1999-2003 time intervals, respectively. The alternative hypothesis that anthropogenic and natural spatial variations over latitude (y direction) have effect on fractional coverage was accepted. These variations significantly increased 3.7% (:I: 0.3), at a = 0.01, of fractional coverage values for each 100 kilometer towards North. On the other hand, the null hypothesis could not be rejected for changes in longitude (x direction), which means that there is no significant change, at a = 0.01, of fractional coverage values when moving towards east or west direction, holding fixed all other factors affecting fractional coverage values. Appendix 8.10 shows further results of the linear multi-regression analysis. It was also observed that forest regeneration increases fractional coverage in the year immediately following selective logging activities and forest fires. The peak of this forest regeneration was observed 3 years following the harvesting year for logging and 5 years following forest fire. 2.6. Conclusions Modified vegetation indices AFRI and MSAVIaf showed good performance in predicting forest canopy cover under smoke condition. AF RI and MSAVIaf also showed high correlation with NDVI and MSAVI, respectively. However, it was observed that fractional coverage derived from MSAVI and MSAVIaf predicted fractional coverage slightly better than the other tested vegetation indices when 67 compared to field measurements in this study area. Additionally, fractional coverage, as a linear unmixing model in vegetation index domain retrieved from Landsat TM and ETM+ imagery, showed to be useful in measuring forest canopy degradation and regeneration in tropical evergreen forests. The land use and land cover dramatically changed from 1992 to 2004 in this study area. More than 29% of the study area, approximately 8,521 kmz, was converted into agricultural land by 2004. More than 19%, 4%, and 1% of the deforested area was previously detected as logged forest, burned forest, and logged and burned forest, respectively, in the 1992-04 time period. In addition to outright deforestation, forests disturbed by selective logging and forest fires represented approximately 40% of this study area by that year. Assuming that this observed trend of land use and land cover conversion continues, there will be no undisturbed forests remaining by 2011. In this context, selective logging only is by far the most important factor of forest disturbances of large extent in the study site. Selective logging only was responsible for the disturbance of more than 9,200 km2 of natural forests by 2004, which corresponds to more than 31% of the total study area. Indeed, large areas of tropical forests have been damaged or impoverished each year by selective logging activities in the Brazilian Amazon (Uhl and Vieira, 1989, Verissimo et al., 1995, Houghton, 1997, Nepstad et al., 1999). Roughly 2350 km2 were degraded by forest fire or a combination of forest fires and selective logging by 2004. This corresponds to less than 26% of the total forest disturbed by selective logging only. 68 During this given period of analysis, there was a large increase of revisited logging and recurrent forest fires. In this study area, more than 3,300 km2 and 800 km2 of cumulative area of revisited logging and recurrent fire was observed by 2004, respectively. I defined revisit logging and recurrent fire as logging and burned forest detected in areas of previous logging and forest fire, respectively, that had recovered sufficiently to become undetectable for one or more years prior to the return of the loggers or forest fire. An annual average of 27.8 km2 (1: 26), 255.4 km2 (:I: 152.8), and 445.8 km2 (1 74.8) of revisit logging was observed for 1992-95, 1996-99, and 2000-04, respectively. An annual average of 38.9 km2 (3: 33.9), 38.5 km2 (s 61.6), and 59.1 km2 (s 46.3) of recurrent fire was observed for 1992-95, 1996-99, and 2000-04, respectively. Recurrent forest fire is likely to increase even more in the next years in this region. According to (Cochrane and Schulze, 1998), once burned for the first time, chances of recurring fires are increased as well. Based on the results of this multi-temporal analysis of fractional coverage derived from Landsat TM and ETM+ imagery, new areas of selective logging only decreased fractional coverage by an average of 4.8% in the study area. Newly burned forests alone and selectively logged and burned forests combined decreased an additional 24% and 31 % of forest canopy cover, respectively, compared to newly logged forests only. Old areas of selective logging and forest fire combined that were still detectable, also showed a substantial decrease of 25.1% of fractional coverage values compared to undisturbed forests. A fractional coverage decrease of 4.3% was observed for old selectively logged 69 and burned forest even after they become undetectable on Landsat images. Although forest fires disturbed a smaller extent of natural forest than selective logging in this study site, when it occurs, as observed by Uhl and Kauffman (1990), its impacts can be devastating for tropical rainforests. Fractional coverage values for old selectively logged forests were 3.3% greater than fractional coverage values for undisturbed forests. These previously selectively logged forests accounted for more than 60% of the total disturbed forest in the study site by 2004. This finding implies that selective logging may be a carbon source immediately following its activities but it may become a carbon sink in the subsequent years. Therefore, further research is required to accurately infer how much selective logging has been contributing to the carbon cycle either as source or as sink in tropical areas. This amount may vary according to forest characteristics, logging and fire intensity, and forest capacity of regeneration of each site. These research results indicate that forests are capable of a strong canopy regeneration following logging activities and forest fires. Approximately 70% of the total area of disturbed forests by logging and fire had sufficiently recovered to become undetectable on satellite imagery by 2004. Forest regeneration, however, may vary according to logging and fire intensity, but in general it takes more time if burned. Selectively logged forests can be detected using Landsat imagery from 3 to 5 years following logging activities and burned forests may persist detectable from 3 to 10 years, depending on fire intensity and forest regeneration capacity. 70 CHAPTER III Basin-Wide Assessment of Forest Disturbances by Selective Logging and Forest Fires 3.1. Abstract The rapid and drastic environmental changes happening in the Brazilian Amazon because of widespread deforestation have attracted the attention of the scientific community for several decades. An area of particular interest involves the assessment of the impacts of selective logging and forest fires. Forest disturbances by selective logging and forest fires may vary in scale, from local damages to the local environment (microclimate, habitats destruction, species extirpation, etc.), to global changes, mostly related to the increase of atmospheric carbon dioxide released into the atmosphere. Selective logging activities and forest fires have been reported by many studies as important agents of land use and land cover changes but yet have to be properly addressed, especially at large scale in tropical regions. Previous studies have focused on a few study sites or were limited to estimate the extent of selective logging. Therefore, this study involved a more comprehensive study of multi-temporal and basin-wide changes of forest disturbances by selective logging and forest fires using remotely sensed data acquired in 1992, 1996, and 1999. Methods for detecting burned forests and estimating forest canopy cover were researched. Finally, I conducted rigorous ground measurements and observations for assessing local impacts of selective logging and forest fires in three different states in the Brazilian Amazon. The results of this study showed a substantial increase in total 71 areas of selectively logged and burned forests, changing from approximately 11800 km2 to 35600 km2 by 1992 and 1999, respectively. Selective logging only was responsible for 60.4% of this forest disturbance in the studied period. Approximately 33% and 7% of forest disturbances detected in the same period were due to impacts of forest fire only and selective logging and forest fire combined, respectively. Most of the degraded forests (~90%) were detected in the States of Mato Grosso and Para. My estimates indicate that approximately 5467 kmz, 7618 kmz, and 17437 km2 were new areas of selective logging and/or forest fires in 1992, 1996, and 1999, respectively. Protected areas seemed to be very effective in constraining these types of forest degradation. Approximately 2.4% and 1.3% of the total detected selectively logged and burned forests, respectively, were geographically located within protected areas. I observed, however, an increasing trend for these anthropogenic activities to occur within the limits of protected areas from 1992 to 1999. Although forest fires impacted the least extent of natural forests, new areas of burned forests detected in 1996 and 1999 were responsible for the greatest impact on canopy cover, with an estimated loss of 18.8% of forest canopy when compared to undisturbed forests. Selective logging and forest fire combined impacted even more those canopies, with an estimated loss of 27.5% of forest canopy. Selectively logged forest only showed the least impact on canopy cover, with an estimated loss of 5% of forest canopy. Field measurements indicated a significant positive correlation between forest canopy openness and tree mortality rate and dead basal area, and a negative correlation between canopy openness and tree diversity. Selectively 72 logged forests had lesser impacts on tree species diversity than did those burned forests. Selectively logged forests also showed stronger and faster forest regeneration than burned forests, following these forest impact events. 3.2. Introduction Natural forests in the Brazilian Amazon have been increasingly exposed to selective logging activities and forest fires (Nepstad et al., 1999, Cochrane et al., 2004, Asner et al., 2005, Matricardi et al., 2005, Matricardi et al., 2007). In contrast to deforestation that converts large extents of natural forests into agricultural lands, selective logging targets cutting down a few most marketable tree species and leave behind of its activities highly disturbed forest patches in which tree fall gaps, access roads, logging patios, and damaged trees are abundant (Stone and Lefebvre, 1998, Nepstad et al., 1999, Souza and Barreto, 2000). Similarly to forest fragmentation that frequently occurs between the edges of deforestation and forested areas, selective logging can increase forest fire susceptibility as tropical forest becomes more fragmented (Cochrane, 2001). Agricultural plots that frequently use fire as land management technique serve as ignition sources and fragmented forests increase the chance of spreading forest fire throughout the Amazon region (Uhl and Buschbacher, 1985, Uhl and Kauffman, 1990, Cochrane, 2001). The consequences of forest fires, however, can be devastating for those natural forests (Uhl and Kauffman, 1990). Although selective logging and forest fires are considered important anthropogenic activities in tropical regions, only a few attempts towards a spatially explicit classification of both activities using remotely sensed data have 73 been conducted in the Brazilian Amazon. The first basin-wide selective logging estimate was conducted by Nepstad et al. (1999) and it was based on a survey of sawmills’ production in the Amazon. These authors estimated that 9,000 to 15,000 km2 of natural forest had been selectively logged in 1996-97 period. Matricardi et al. (2007) detected and mapped selectively logged areas in the Brazilian Amazon using Landsat imagery acquired in 1992, 1996, and 1999. In that study, a total of 5980 kmz, 10064 kmz, and 28085 km2 of selectively logged forests were detected by 1992, 1996, and 1999, respectively. Matricardi et al. (2007) estimated an increase of new areas of selective logging in the Brazilian Amazon around of 2547 kmz, 4381 kmz, 11889 km2 in 1992, 1996, and 1999, respectively. A more recent multi-annual analysis of selective logging from 1999 to 2002 was conducted by Asner et al. (2005) in five major timber centers of the Brazilian Amazon, using remotely sensed data. These authors observed an increase around of 19800 kmz, 14200 kmz, and 12000 km2 of selectively logged forests in 1999-00, 2000-01, 2001-02 periods, respectively. In addition to selective logging activities, forest fires are increasingly contributing to forest degradation in the Amazon region. Although fire is an important agent of land use and land cover change, it has yet to be properly assessed (Schroeder et al., 2005). Most large scale analyses of fire in the Amazon region have been based on general information, manly focusing on the geographic location of fires based on thermal bands and course spatial resolution satellite products. Maps of fire locations or fire pixels have been generated in a daily basis by the National Institute for Space Research (INPE) in Brazil. Most of 74 those maps are based on NOAA3 and MODIS4 products (http://www.cptec.inpebr/queimadasl) and are available for the entire South America continent. Schroeder et al. (2005) used the INPE products to analyze spatiotemporal dynamics of fire in the Brazilian Amazon. These authors had to integrate various datasets to improve spatial scale and reduce analytical uncertainties caused by the use of a single sensor. Complementary and more detailed researches have been restricted to small study areas (e.g. Cochrane and Schulze, 1998, Souza et al., 2005) and are not sufficient for a more comprehensive analysis of forest fires (Schroeder et al., 2005) and selective logging in the Amazon region (Matricardi et al., 2007). Based on the existing knowledge gaps, I conducted a comprehensive research of forest degradation due to selective logging activities and forest fires based on remotely sensed data and ground measurements in the Brazilian Amazon. In addition to employing the selective logging dataset created by Matricardi et al. (2007), I developed and applied a fully automated remote sensing approach based on SMA (Spectral Mixture Analysis) to detect and map burned forests basin-wide. Fractional coverage was retrieved from Landsat imagery and used to assess forest canopy impacts by selective logging and forest fires. This analysis was conducted on a time-series of Landsat TM and ETM+ imagery acquired in 1992, 1996, and 1999. Field measurements and observations included three different regions in the Amazon States of Acre, 3 NOAA: A series of Geostationary and Polar-Orbiting Weather Satellites operated by the National Oceanic and Atmospheric Administration, USA; ‘ MODIS: Moderate Resolution Imaging Spectroradiometer sensor aboard of Terra and Aqua satellites, both operated by the National Aeronautics and Space Administration, USA. 75 Rond6nia, and Mato Grosso. The field information was used to assess forest impacts caused by selective logging and forest fires on forested areas and to validate remote sensing approaches. The results of this study will contribute to improve land use classification maps and to expand current understanding of the characteristics and interactions between forest fire and selective logging, and fire and other land management practices in the study region. The applied use of these results by governmental and non-governmental organizations may contribute to improve sustainable forest management, environmental monitoring, and law enforcement activities in the Brazilian Amazon. 3.3. Methods 3.3.1. Regional setting The study region was Brazil’s Legal Amazon, a territory with approximately 5 million kmz. The so-called Legal Amazon includes the totality of Acre, Amapa, Amazonas, Para, Rondcnia, and Roraima States, plus parts of Mato Grosso, Maranhao, and Tocantins (see Appendix C1). The Legal Amazon is a political-administrative region in Brazil, created by the Brazilian Federal Law 1806 in 1953. This analysis was conducted using more than 600 Landsat images of the Legal Amazon, previously used for deforestation analysis at the Tropical Rain Forest Information Center (T RF IC), of the Michigan State University. Signs of selective logging and forest fire were searched throughout the study region. Matricardi et al. (2007) found evidences of selective logging in 31 Landsat TM scenes acquired in 1992 and 1996, and in 38 Landsat ETM+ scenes acquired in 1999. Evidence of forest fires also was found on these scenes and, 76 complementarily, for 1992 and 1996, additional 6 scenes acquired in 1992 and 1996 were used and for 1999, additional 7 scenes acquired in 1999 were used. These Landsat scenes defined the subsequent effective areas of study used in this analysis (Appendix 01). 3.3.2. Dataset 3.3.2.1. Deforestation dataset The Brazilian Amazon is one of the regions covered by the deforestation monitoring project implemented by the Tropical Rain Forest lnforrnation Center (httpzllwwwtrficmsuedu) at Michigan State University, which involved a multi- annual classification of 229 Landsat scenes. In that study, Landsat images were individually classified into seven thematic classes: forest, deforestation, regrowth, cenedo 5, cloud, cloud shadow, and water using unsupervised image classification procedures. Classified Landsat scenes (path/row) were available individually and placed together as deforestation mosaics for the entire Brazilian Amazon. These deforestation mosaics preserved the original spatial resolution (30 meters). Additional details of the deforestation dataset are presented in Table 3.1. Selectively logged and burned forests were not included in these land use and land cover classes. Both individual Landsat scenes and deforestation mosaics for 1992, 1996, and 1999, produced by the TRFIC at Michigan State University, were used to perform the intended analytical procedures. 5 Cerrado is a vegetation type similar to African Savannah. 77 Table 3.1 Deforestation dataset characteristics Dataset Features Format Spatial Period of Projection resolution Analysis Land use Forest, Arc/Info 30m x 30m 1992, UTM, and land deforestation, grid 1996, and Zones 19 cover GIS secondary 1999 through 23. layers by regrowth, Projection, Landsat cerrado, clouds, Datum, and scene and shadows Spheroid (path/row) WGSB4 Land use Forest, Arc/Info 30m x 30m 1992, Sinusoidal and land deforestation, vector 1996, and projection, cover secondary and grid 1999 Datum and mosaic regrowth, Spheroid cerrado, clouds, WGS84 and shadows 3.3.2.2. Selective logging dataset Unsupervised classification has frequently been applied to assess land use and land cover change in the Brazilian Amazon. This procedure does not detect most of the selectively logged forests. As a result, additional remote sensing techniques were required to accurately detect and map them. Matricardi et al. (2007) conducted a multi-temporal analysis of selective logging of the entire Brazilian Amazon. In that study, forests showing evidences of selective logging were mapped and estimated for up to 38 Landsat scenes throughout the Brazilian Amazon for 1992, 1996 and 1999. The authors used semi-automated (texture algorithm) analysis of Landsat band 5 to detect log landings (i.e. log storage patios) and, subsequently, applied variable buffer zones (180 and 450 meters) around patios to estimate areas affected by selective logging. In addition, Matricardi et al. (2007) mapped selectively logged forests with visible canopy disturbance on Landsat images through visual interpretation, and circumscribed them digitally on a computer screen. In that analysis, visual 78 interpretation and semi-automated method could detect 83.4% and 63.7% of the total logged forests, respectively. Common areas between these two techniques were around 50% but they were not double—counted. Areas that had been previously missed using automatic analysis were added by visual interpretation and vice-versa. Moreover, semi-automated and visual interpretation technique combined showed 92.9% and 0.82 of overall accuracy and overall kappa statistic, respectively. Concomitantly, a deforestation dataset was produced for 1992, 1996, and 1999 and composed by individual Landsat scenes and mosaics for the entire region. Characteristics of the logging dataset are presented in Table 3.2. Table 3.2 Selective Logging dataset characteristics Dataset Classification Format Spatial Period of Projection Features resolution Analysis Selectively Binary classes Arc/Info 30m x 30m 1992, UTM, logged forest (1 = logging, grid 1996, Zones 19, GIS layers 0 = no data) and through 23. (Landsat 1999 Datum and path/row) Spheroid WGS84 Selectively Binary classes Arc/Info 30m x 30m 1992, Sinusoidal, logged forest (1 = logging, grid 1996, Datum and GIS layers 0 = no data) and Spheroid (mosaic) 1999 WGS84 The present study included the previously described selective logging dataset, involving multi—annual measurements for1992, 1996, and 1999 of selectively logged forests in ten'a-fimie (upland) of the Brazilian Amazon. In addition, information derived from a multi-annual analysis of selective logging from 1992 to 2002 for a case study (Landsat scene path226 and row 068) in the 79 State of Mato Grosso, conducted by Matricardi et al. (2005), was used to estimate annual increase of selectively logged forests in the study region. 3.3.2.3. Landsat imagery The Landsat imagery used in this analysis were drawn from the Tropical Rain Forest Information Center (httpzllwwwtrficmsuedu) at Global Observatory for Ecosystem Services, Michigan State University. For 1992 and 1996, 38 Landsat TM5 images were used for the analyses, and for 1999, 46 Landsat ETM+ images were used. Three years (1992, 1996, and 1999) were used as reference for measurements and analytical purposes. Some Landsat images, however, were acquired on previous or following year of reference, according to remotely sensed data availability and quality. Acquisition dates of each Landsat scene used in this analysis are provided in Appendix 02. 3.3.2.3.1. Radiometric correction Remotely sensed data is affected by changes in the instrument over time. In this case, radiometric correction can be used to normalize the sensor degradation to generate products suitable for multi-temporal analysis, especially when the remotely sensed data is derived from different sensors and acquisition dates (Chander and Markham, 2003). Therefore, radiometric correction was conducted for all Landsat scenes used in this analysis. Further details on this correction procedure were shown in Chapter 2. 3.3.2.3.2. Landsat imagery normalization Multi-temporal analysis using satellite imagery may be affected by seasonal variations of landscape components such as soil and vegetation 80 characteristics (Mas, 1999). To prevent this sort of distortion, image normalization may be applied to reduce seasonality effects and atmospheric and sensor variations (Elvidge et al., 1995). Image normalization was applied for all Landsat scenes used in this analysis. A good quality Landsat image, p226/r068 acquired in 1999, was selected as reference. As suggested by Elvidge et al. (1995), the brightest and darkest pixels or sample points were selected from the reference Landsat image and from the corresponding scene acquired in 1996. Sample points consisted of areas of undisturbed forests, soil exposure, and deep water bodies. Around 20 sample points of reflectance values from the reference image (dependent variable) and from the corresponding image acquired in 1996 (independent variable) were used to generate coefficients for a linear regression model. Normalization coefficients (slope and intercept) for each band of interest were produced. The acceptable R2 for each equation was greater than 0.95, and, when needed, additional sample points were acquired to increase it. The equation 1 describes the linear regression model used for image normalization. y = ,50 + 31951 (1) where y is the reference image reflectance (dependent variable), ,60 is the intercept or constant coefficient, ,6, is the parameter associated with x,, and xl is the reflectance of the normalizing image (independent variable). The estimated coefficients and Landsat image acquired in 1996 (independent variable) were used as input to the equation 1, which generated a spectrally adjusted (normalized) image to the reference image. The same 81 procedure was applied to normalize the Landsat image (p226/r068) acquired in 1 992. Common areas (overlaps) observed between Landsat scenes were used to obtain reflectance values of brightest and darkest pixels. In this case, each previously normalized image served as a reference image for its neighboring scene. This procedure was applied for all images acquired In 1999. Consequently, the normalized Landsat imagery acquired in 1999 were used as reference to normalize those acquired in 1992 and 1996. 3.3.2.3.3. Geometric correction The Landsat imagery used in this analysis was previously system- corrected at the TRFIC using sensor geometry and a polynomial distortion model. The root-mean-square (RMS) positional errors resulting from this geometric correction varied from 0.20 to 0.47 pixels. Additionally, ground control points at known locations and intersections of road segments acquired during fieldwork in 2004 were used to test geometric accuracy of three Landsat scenes (p002/r067, p232/r067, and p226/068) located in the States of Acre, Rondbnia, and Mato Grosso. The measurements between these three Landsat scenes and the ground control locations averaged less than 36 meters :I: 31.4 meters and 32 meters 1: 37.1 meters for x and y directions, respectively. 3.3.3. Field study The fieldwork observations and measurements were conducted during June 2003, June and July 2004 in study sites in the States of Acre, Rondonia, and Mato Grosso (Appendix 03). Various types of selective logging (ongoing 82 and previous logging), logged and burned forests, and undisturbed forests were sampled across the study sites. The study site locations and characteristics are described in Appendix 04. The field studies were designed to enhance the accuracy assessment of remote sensing approaches and to support further analysis of forest disturbances. 3.3.3.1. Field sampling and measurement Field survey sampling was necessary to estimate the potential biological composition changes of several forest use types (undisturbed, selective logging, and forest fire). Fuel load such as dead trees, wood debris, and litter were also quantified in each study site. Moreover, various forest degradation types and intensities were identified and sampled (Appendix 04). Therefore, this survey included simultaneous measurements of fuel load and forest composition and regeneration assessments. A sampling design scheme developed by Cochrane and Schulze (1998) was used to guarantee accuracy and precision of the field survey. As a result, the sample unit was the same for all sampled sites (Appendix C.5). Twenty transects (approximately 9.4 hectares) were plotted and measured in Acre, Rond6nia, and Mato Grosso. Each sampled site was geographically located using a GPS. The sample unit on the ground consisted of one transect of 500 x 10 m in which the number of trees, tree identification, tree condition (i.e. dead, alive, rotten, or broken), and DBH measurement of trees greater than 10 cm DBH were recorded. Within the main transect, a quadrat of 10 x 10 m was also plotted every 25 m. Each 10 x 10 m quadrat contained a nested sub-quadrat of 5 x 5 m 83 for sampling tree regeneration and trees within two different diameter classes (< 5 cm and 5-10 cm). Secondary regrowth species and biomass (i.e. dry, rotten, alive, broken, etc.) were identified within the sub-quadrats (DBH < 10 cm) and main transects (DBH >10 cm). Additionally, along each main transect a 10 m fuel line was plotted every 25 m. Each fuel line started at the center of every quadrat (Q1, Q2, Q3, or Q4) towards a randomized direction (0° to 90°, 90° to 180°, 180° to 270°, and 270° to 360° for Q1, Q2, Q3, and Q4, respectively). Subsequently, litter depth was measured at the beginning, middle, and end of the line. In addition, the remaining biomass under the last meter, under the last three meters, and under the entire line for classes of diameter less than 2.5 cm, between 2.5 and 7.6 cm, and greater than 7.6 cm were also counted. Finally, hemispherical photos were acquired every 10 m along the main transect line. These photos were used to measure canopy openness in each location. 3.3.3.2. Identification of species Identification of tree species was one of the most difficult tasks during the field survey. In theory, plant components could be collected and properly identified in a herbarium (e.g. Emilio Goeldi Museum in the State of Para). However, in practical terms, a great amount of time, energy, and financial resources would be required to fulfill this task. To avoid such logistical trap, I used the help of a Mateiro6 in each study area to make an approximate 6 A Mateiro is a knowledgeable local person whom has been working in a given area long enough to have the ability to identify most of the tree species using common or local names. 84 identification of most tree species. Finally, I used a description of trees produced by the Brazilian Institute of Environment and Renewable Natural Resources- IBAMA to provide the scientific name for each tree species previously identified in the field. Scientific names helped to avoid double counting of the tree species identified by local names. 3.3.3.3. Data processing for biodiversity Forest diversity can be quantified in many different ways. Key measurement concepts of the measurement of diversity include specie richness, heterogeneity, and equitability. Alternative approaches to measure biological diversity suggested by Peet (1974) are based on specie richness and heterogeneity indices. Species richness is an indicator of species diversity based on the number of species per sample. As a result, biological richness will increase as the number of species observed in a sample increases. Therefore, richness is dependent of the sample size. Following this reasoning, a larger sample size with more species present will be understood as a 'richer' sample. Alternatively, heterogeneity indices can measure diversity by taking into account the number and equitability (relative diversity) of species and, because of that, these indices are less sensitive to sample size (Peet, 1974). To compare tree species diversity of different sample sizes conducted in the State of Acre, Rond6nia, and Mato Grosso, I applied two heterogeneity indices that are not sensitive to sample size, the Simpson’s Index of Diversity (1- D) and the Simpson’s Reciprocal Index (1/D), both variants of Simpson’s Index (D) (Peet, 1974). The Simpson’s Index of Diversity varies directly with 85 heterogeneity and ranges between 0 and 1, where higher values indicate greater species diversity. This index can be defined as: S D =1— 2H p,-2 (2) The Simpson’s Reciprocal Index starts with 1 as the lowest possible value, representing a community containing only one species, and the maximum value is the number of species in the sample. It can be defined as: N S D=1/Z,=,pi (3) where D and D is the Simpson’s Index of Diversity and the Simpson’s Reciprocal Index, respectively, p, is the proportion of individuals in species i, and S is the number of species (Peet, 1974). 3.3.3.4. Field validation for remote sensing approaches Canopy openness was measured for both disturbed and undisturbed forests using hemispherical photos (further details are provided below). Similarly, tree species diversity (including secondary tree species) was qualitatively and quantitatively established for each site. Hemispherical photos acquired with “fish eye” lens and digital camera (3.2 mega pixels resolution) beneath undisturbed and disturbed forest canopies were used to estimate canopy openness. The photo-shots follow 500 meter transect trails, for each 10-meter intervals. Canopy openness measurement for each individual location was calculated using the Gap Light Analyzer (GLA) software. Fraction canopy openness was estimated using a semi-automated technique because each individual photo requires a 86 threshold empirically defined by the photo interpreter (Appendix 8.6). Subsequently, the canopy fraction was obtained by calculating the difference between 100% and forest canopy openness (%) calculated from the hemispherical photos. Finally, potential occurrences of forest fires were surveyed in 120 randomly distributed locations of forested lands within the Landsat path 226 and row 068. The resulting information was used to perform an accuracy assessment of the burned forest detection technique. Further details of the accuracy assessment of burned forest detection are described in Chapter 2. 3.3.4. Remote sensing approaches 3.3.4.1. Burned forests detection Burned forests were detected and mapped using a remote sensing approach based on Spectral Mixture Analysis. This approach was successfully applied by Cochrane and Sousa Jr (1998) and Souza et al. (2003) to detect selectively logged and burned forests using Spot imagery in a case study in the State of Para, Brazil. Cochrane and Sousa Jr (1998) used fraction images based on particular endmembers (spectral pure signatures) that represented specific image components such as green vegetation, soil, non-photosynthetic vegetation, and shade. Based on this approach, a fully automated technique was developed and tested to detect burned forests using non-photosynthetic vegetation fraction image from Spectral Mixture Analysis (SMA), retrieved from Landsat imagery. This technique was developed and tested for a 30000 km2 study site in the Amazon State of Mato Grosso. Accuracy assessment results 87 indicated 96.0% and 0.91 of overall accuracy and overall kappa statistic, respectively. Additional details regarding this technique and its usage can be found in Chapter 2. The approach introduced in Chapter 2 was applied where signs of burned forest were observed throughout the Brazilian Amazon. Burned forests were detected and binary classified (1 = burned forest, 0 = non-burned forest) in raster format for 1992, 1996, and 1999. 3.3.4.2. Fractional coverage The theoretical foundation for the assessment of forest canopy impacts by selective logging and forest fires using vegetation index derived from remotely sensed data was previously described in Chapter 2 for a case study in the State of Mato Grosso. In that study, Modified Soil-Adjusted Vegetation Index - MSAVI, Global Environmental Monitoring Index - GEMI, modified GEMI“, Normalized Difference Vegetation Index - NDVI, Aerosol Free Vegetation Index - AFRI, Modified Soil-Adjusted Vegetation Index aerosol free — MSAVIaf, and Green Vegetation derived from Spectral Mixture Analysis were retrieved from the Landsat path 226 and row 068, and their performance was assessed under different atmospheric conditions and forest characteristics. For the basin-wide analysis purposes, two additional case studies in the Amazon States of Rondonia and Acre (Appendix C.3) were conducted in the present study. Vegetation indices’ performances were assessed again for different Amazon sub-regions and forest sites by comparing fractional coverage values derived from remotely sensed data to canopy cover measurements from 88 hemispherical photos acquired in the field. This assessment contributed to select the optimum vegetation index to be applied in the basin-wide analysis. Time-scale variation of forest canopy also was verified through multi- temporal analysis of fractional coverage retrieved from Landsat imagery acquired in 1992, 1996, and 1999. Finally, partial effects of each land use and land cover change on fractional coverage were identified using multiple regression analysis. Further details of this multiple regression analysis are described bellow. 3.3.5. Forest canopy impact assessment Forest canopy degradation by selective logging, forest fire, logging and forest fire combined, and forest regeneration following each of these forest disturbances in the study area were assessed using multiple regression analysis. Multiple regression analysis is useful to estimate partial effects of a given independent variable by controlling other independent variables that simultaneously affect the dependent variable (Wooldridge, 2000). Based on Wooldridge (2000), the multiple linear regression model can be defined as: FC%: [30 +iBIxI +3239 +---+,314x14 +14: (4) where FC% is the observed continuous variable (green fractional percentage derived from remotely sensed data), and ,60 is the intercept or constant, ,3] is the parameter associated with x1 (independent variable 1), ,62 is the parameter associated with x2 (independent variable 2) and so on. The variable u is the error term, which contains factors other than the independent variables included in this model that affect FC%. 89 The vector of independent variables (x) tested is described as following: x1= Deforestation x2 = Secondary regrowth x3 = Water body x4 = Cerrado or Savannah x5 = Newly logged forest x6 = Newly logged and burned forest x7 = Newly burned forest x8 = Previously logged forest x9 = Previously burned forest x10 = Previously logged and burned forest X11= Year 1996 X1; = Year 1999 x13 = Longitude or x location (kilometer) x14 = Latitude or y location (kilometer) OOOOOOOOOOOOOO Note: Undisturbed forest and the year 1992 were used as omitted variables for the land use classes and annual changes, respectively. By using this multiple regression analysis, I was able to measure the effect of each land use or year of analysis on forest canopy cover in the study area, holding constant the other independent variables. 3.3.5.1. Testing Hypotheses Based on field observations, I expected that impacts by anthropogenic activities should produce measurable effects on forest canopy. Therefore, any observed type of land use and land cover should affect (increase or decrease) values of fractional coverage derived from Landsat imagery when compared to undisturbed forests. I also expected that effects of non-controlled seasonal and natural variations should have effects on values of fractional coverage, which ultimately could be observed by using multi-temporal dataset. Finally, I expected that values of fractional coverage could be affected by uncontrolled spatial variability of natural forests and human activities in the study area. In this case, 90 location itself could be used to identify potential spatial variation of fractional coverage values throughout the study region. Based on these assumptions, l hypothesized about each value of the fourteen slope coefficients (,6, ”62, ...,,6,4 ), once the effect of other coefficients had been account for, using statistical inferences to test the following hypothesis: Ho: Null hypothesis: Land use and land cover change variables (,6, to 6,0 ): ,6, = 0: Deforestation has no effect on fractional coverage. ,62 = 0: Secondary regrowth has no effect on fractional coverage. ,63 = 0: Cerrado has no effect on fractional coverage. ,64 = 0: Water body has no effect on fractional coverage. ,65 = 0: Newly logged forest has no effect on fractional coverage. ,66 = 0: Newly burned forest has no effect on fractional coverage. ,67 = 0: Newly logged and burned forest has no effect on fractional coverage. ,68 = 0: Previously logged forest has no effect on fractional coverage. ,69 = 0: Previously burned forest has no effect on fractional coverage. 6,0 = 0: Previously logged and burned forest has no effect on fractional coverage. Temporal variables (,6, , to 6,2 ): ,6,, = 0: Non-controlled seasonal or temporal variations for 1996 have no effect on fractional coverage. 6,2 = 0: Non-controlled seasonal or temporal variations for 1999 have no effect on fractional coverage. Spatial variables (63 to ,624 ): ,6,3 = 0: Anthropogenic and natural spatial variations over longitude (x) direction have no effect on fractional coverage. 6,4 = 0: Anthropogenic and natural spatial variations over latitude (y) direction have no effect on fractional coverage. H1: Alternative hypothesis: Land use and land cover change variables (,6, to 6,0 ): ,6, ¢ 0: Deforestation has effect on fractional coverage. ,62 at 0: Secondary regrowth has effect on fractional coverage. ,63 -'/-' 0: Cerrado has effect on fractional coverage. ,64 it 0: Water body has effect on fractional coverage. 91 ,65 it 0: Newly logged forest has effect on fractional coverage. ,66 it 0: Newly burned forest has effect on fractional coverage. ,67 75 0: Newly logged and burned forest has effect on fractional coverage. ,68 ¢ 0: Previously logged forest has effect on fractional coverage. ,69 it 0: Previously burned forest has effect on fractional coverage. 6,0 at 0: Previously logged and burned forest has effect on fractional coverage. Temporal variables ( ,6, , to 6,2 ): ,6, , ¢ 0: Non-controlled seasonal and temporal variations for 1996 have effect on fractional coverage. 6,2 it 0: Non-controlled seasonal and temporal variations for 1999 have effect on fractional coverage. Spatial variables ( 6,3 to ,6, 4 ): ,6,3 76 0: Anthropogenic and natural spatial variations over longitude (x) direction have effect on fractional coverage. 6,4 it 0: Anthropogenic and natural spatial variations over latitude (y) direction have effect on fractional coverage. 3.3.5.2. Data Sampling As previously discussed in Chapter 2, multiple linear regression models are sensitive to spatial auto-correlation in the dataset. The auto-correlation effects can be minimized by systematically sampling the dataset (Anselin 2002, Arima et al. 2007). Therefore, I used a 5km x 5km point grid to sample all variables of interest over the study region (Appendix C.1). Since pixel was used as the unit of observation in this analysis, a unique value of the dataset was acquired for each point of the sampling grid to represent each of the studied variables. Additionally, each grid cell was located with x and y coordinates, which also were used as independent variables. This procedure is expected to allow the identification of spatial trends in the data and to reduce the error term in the 92 regression model due to spatial autocorrelation in the data population (Chomitz and Gray 1996, Arima et al. 2007). 3.4. Results and Discussion 3.4.1 . Multi-temporal assessment of selective logging and forest fires Matricardi et al. (2007) developed remote sensing approaches to detect selectively logged forests in the entire Brazilian Amazon. Using such approaches, a total of 5980 kmz, 10064 kmz, and 26085 km2 of selectively logged forests were detected in 1992, 1996, and 1999, respectively. By using linear mixture analysis, I could detect 8280 kmz, 7580 km2, and 11508 km2 of burned forests in the Brazilian Amazon in 1992, 1996, and 1999, respectively. The total area of tropical forests impacted by selective logging and forest fire and detected using remotely sensed data were 11800 kmz, 16500 kmz, and 35600 km2 in 1992, 1996, and 1999, respectively. This magnitude of degraded forests had not been reported in previous studies of deforestation (Skole et al., 2004). Table 3.3 shows further details of the detected areas of selectively logged and burned forests, taking into account the overlap between both types of forest disturbances. Table 3.3 Detected selective logging, burned forests, and dataset characteristics Year Burned only Burned & Logged Logged only Total degraded (km2) 4km2) 4km2) (km ) 1992 5,889.4 391.8 5,588.2 11,8893 1998 8,177.7 1.4033(3) 8,951.0 18,5320 1999 9,038.4 2,470.7(“) 24,188.1 35,897.3 a Total includes 290.2 km2 of burned forest detected in 1996, which was previous logging detected in 1992 and not detected in 1996; Total includes 573.4 km2 of burned forest detected in 1999, which was previous logging detected by 1996 and not detected in 1999. 93 Landsat path and row analysis indicated that 1205 km2, 1719 kmz, and 4241 km2 of selective logging were detected in 1992, 1996, and 1999, respectively, within the path 226 and row 068, located in Mato Grosso. This was the greatest forest extension impacted by selective logging for a particular Landsat scene (path/row) in the entire Brazilian Amazon. Meanwhile, the greatest extension of burned forest detected was observed within the path 222 and row 063 in 1992 (around of 644 km2) and within the path 224/068 in 1996 and 1999 (around of 605 km2 and 1227 kmz, respectively). Appendix C.9 shows basin-wide results of selectively logged and burned forest detected within each Landsat path and row in 1992, 1996, and 1999. Most of the detectable burned and selectively logged forests were observed in Mato Grosso and Para. These two states accounted for more than 90% of total selective logging only, 89% of total burned forest only, and 87% of total selectively logged and burned forest combined detected in 1992, 1996, and 1999. Mato Grosso was responsible for approximately 59% of burned forest in 1992 and Para was responsible for approximately 76% of selectively logged and burned forests detected in 1996 (Appendix 0.10). An additional element of concern in this analysis was related to the occurrence of forest disturbances within the borders of land set aside from economic development for different types of non-economic uses. Around 1.8%, 2.3%, and 4.7% of the total selectively logged forests were detected within the limits of Amerindian reserves, protected lands, and military areas in 1992, 1996, and 1999, respectively (Matricardi et al., 2007). Approximately 0.6%, 2.6%, and 94 5.1% of the total forests burned were detected within these areas in 1992, 1996, and 1999, respectively. Amerindian reserves constituted the vast majority of the detected selectively logged and burned forests within these areas (Table 3.4). Table 3.4.Total area of selectively logged and burned forests detected in 1992, 1996, and 1999 within protected areas (indigenous land, conservation unit, and military area) Indigenous land Conservation units Military area Burned Logged Burned Logged Burned Logged Year forest Forest (*) forest Forest (*) forest Forest (*) (km2) (km2) (km2) (km2) (km2) (km2) 1992 33.3 106.5 2.8 3.6 0.0 0.0 1996 193.2 216.6 0.5 11.1 0.0 0.0 1999 574.3 1189.8 17.3 44.7 0.4 0.0 Total 800.8 1512.8 20.5 59.4 0.4 0.0 * Source: Matricardi et al. (2007) Multi-temporal analysis between forest fire and deforestation indicated that 2968 km2 of burned forest only detected in 1992 were deforested by 1996 and an additional 546 km2 by 1999. Around of 3225 km2 of burned forest only detected in 1996 were deforested by 1999. Comparisons between selective logging and deforestation in this period of analysis indicated that 651 km2 of logged forest only detected in 1992 was deforested by 1996 and an additional 708 km2 by 1999. Meanwhile, 984 km2 of logged forest detected in 1996 were deforested by 1999. Additionally, comparisons between deforestation, selective logging, and forest fire indicated that around of 145 km2 of selectively logged and burned forest combined in 1992 were cleared by 1996 and an additional 188 km2 were cleared by 1999. Around of 720 km2 of selectively logged forest in 1992 and/or 95 1996 and burned forest in 1996, were deforested by 1999. These results also showed that around of 457 km2 and 148 km2 of forest disturbances detected could be considered recurrent fires and revisited logging, respectively. I defined recurrent fire and revisited logging as burned and logged forests, respectively, detected in 1992 that had formerly recovered sufficiently to become undetectable in 1996 and again were detected in 1999 as burned or logged forests. 3.4.2. Optimum vegetation index selection In Chapter 2, an optimum vegetation index was selected based on the estimated relationships among various vegetation indices retrieved from a Landsat image and canopy cover derived from hemispherical photos. The statistical results showed that AFRI could perform slightly better than MSAVIa, under clear sky and anomalous atmospheric conditions for the study region in Mato Grosso. However, linear relationship between fractional coverage values derived from each vegetation index and those calculated from hemispherical photos acquired in the field indicated that MSAVI and its modified version (MSAVIaf,) could better estimate forest canopy cover for the same region. Finally, MSAVIa, was selected as the optimum vegetation index given its property of acquiring more accurate ground information than the other indices in the presence of smoke and aerosols. Additional hemispherical photos were acquired in the field sites located in Acre and Rondonia. MSAVI showed highest R-squared for Rond6nia and Acre study sites (0.74 and 0.81, respectively). Immediately following MSAVI, MSAVIaf, GEMI, GEMI“, and GV showed the same R-squared (0.69) for the Rondbnia 96 study site. MSAVIaf showed the second highest R-squared (0.80) for the Acre study site. Based on these statistical results and on its performance under clear and smoke sky condition, I selected MSAVIa, as the optimum vegetation index to be used in this basin-wide analysis. The Appendix C.8 shows the statistical results of the empirical linear relationship between various vegetation indices and forest canopy coverage based on field measurements for the study sites in Mato Grosso, Rond6nia, and Acre. 3.4.3. Forest canopy impact assessment based on remotely sensed data Impacts on forest canopy by selective logging and forest fire were estimated using a multiple regression model (Equation 4) and land use and fractional coverage derived from remotely sensed data. The statistical results indicated that this equation can significantly explain 52.8% of the dependent variable (fractional coverage). Analysis of the partial effects of different anthropogenic activities that potentially could be affecting fractional coverage derived from vegetation index domain in the study region from 1992 to 1999 indicated that deforestation alone was responsible for a decrease of 49% (d: 0.38) in the fractional coverage values when compared to fractional coverage values for undisturbed forests and holding fixed all other factors. Although secondary regrowth is defined as a formerly deforested area, this land use was much less responsible for the reduction of fractional coverage values (around of 7%) than was deforestation itself. In terms of forest uses, around of 28%, 19.8%, and 2% of estimated forest canopy decreases in the studied period were due to new areas of selective 97 logging and forest fire combined, forest fire only, and selective logging only, respectively. Previously burned and logged forests were responsible to decrease approximately 10% of fractional coverage values. When considered previously burned forest only, I could not reject the null hypothesis that fractional coverage values for this forest use are not significantly different from fractional coverage values for undisturbed forests (omitted variable). My analysis also indicated that forest canopy is sufficiently recovering after selective logging activities throughout the Legal Amazon and such recovery was responsible for an increase of approximately 6% in fractional coverage values when compared to undisturbed forests. Figure 3.1 shows partial effects of each anthropogenic activitv on forest canopv change. 15.00 10.00 5.00 0.00 —5.00 -10.00 -15.00 —20.00 -25.00 -30.00 -35.00 Canopy change (% t'iil'e’wiy loggiediforiest ’ ’ ’ T ENewIJSJmeIrcYest l Newly logged/burned forest [I Previously logged forest _ Previously burned forest :1 Previously logged/burned forest Figure 3.1. Partial effects of various anthropogenic activities on forest canopy cover in the Brazilian Amazon using linear multiple-regression model and multi- temporal remotely sensed data 98 The null hypothesis that anthropogenic and natural spatial variations over longitude and latitude (x and y) directions have no effect on fractional coverage values could be rejected and the alternative hypothesis was consequently accepted. Fractional coverage values significantly decrease 0.8% (3: 0.03 standard deviation) each 100 km towards east direction and significantly increase 1.2% (:I: 0.04) each 100 km towards north direction. In terms of temporal change, the results indicated an increase of 1% of fractional values in 1996 compared to year 1992 and by holding all other independent variables fixed. The greatest annual loss of fractional coverage, around 5% (:I: 0.3), was observed in 1999. A possible explanation is related to the factors that vary annually, such as the rainfall reduction caused by the 1997-1998 “El Nino” observed by Siegert et al. (2001), absent in the list of independent variables, may have contributed to decrease fractional coverage in 1999. Appendix C.11 shows further results of the linear multi-regression analysis and Appendices 018 to 0.20 show mosaics of fractional coverage derived from Landsat imagery acquired in 1992, 1996, and 1999 for the study region. 3.4.4. Field measurements In the field survey conducted in the States of Acre, Rondcnia, and Mato Grosso, a total of 3269 individuals of tree species (DBH > 10 cm) were recorded for an area of 9.38 hectares, an average greater than 348 tree individuals per hectare. This estimate is well in the range of Whitmore’s (1984) estimate that indicated 250 or more species of trees DBH greater than 10 cm for tropical rain forests. Approximately 80% of the total observed tree species observed in the 99 present study could be identified by the Mateiros, which indicated that a minimum of 119 different tree species were observed in those sampled sites (Appendix C6). The number of new tree species decreased as the sample size (number of transects) increased. The number of tree species also increased between the transects #3 and #4 and between transects #8 and #9, which represented the transition sites between the State of Acre and Ronddnia and between the State of Rond6nia and Mato Grosso, respectively. The observed increase of new tree species in the first samples for each sampled region indicated potential differences in tree species diversity among the study sites. However, the fact that the same Mateiro was not available to assist the field work data gathering process in three regions, could have affected the detected number of unknown species. Based on field observations, the sites sampled in Acre and Rondcnia seemed to have greater number of tree species (DBH > 10 cm) than did those sites located in Mato Grosso. Forest disturbances by selective logging and forest fire were also visually more intensive in Mato Grosso. Based on these facts, I expected that tree species diversity would be higher in Acre and Rondcnia. Statistical results (t-test for independent groups, p1¢u2) confirmed that sampled sites in Rond6nia and Acre combined had higher Simpson’s Diversity Index (M: 0.94, fl= 0.008) than did those sites sampled in Mato Grosso only (M = 0.81, E =0.087). This difference was significant, 1(18) = 3.9937, g = .0004. Similarly, sites in Rondbnia and Acre combined had significantly higher Simpson’s 100 Reciprocal Index (M: 16.3, S_D= 2.31) than did those sites in Mato Grosso only (M = 6.1, S_D =1.88), 1(18) = 10.8658, 9 = .0000. The greatest decrease of tree species diversity index was observed for a severely burned site (transect # 20) in Mato Grosso. The Simpson’s Index of Diversity, Simpson’s Reciprocal Index, and the number of tree species variation across the sampled sites are shown in Figure 3.2. 140 120 . 1005 0 i i t t . 1 f i i l . 4 i t i i i l . 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 TransectlD + Nrrberoftree species (DBH> 10cm) + Sirrpsorls Reciprocal hdex(1lD) —o— Sirrpsorls Diversityhdex(1-D) Figure 3.2. Number of tree species, Simpson’s index of diversity, and Simpson’s reciprocal index against number of sampling (transect) By grouping the sampled sites in undisturbed and disturbed (logged and/or burned) forests, the difference of mean values of Simpson’s Index of Diversity for these two groups was not significantly different from zero (undisturbed M = 0.90, S_D = 0.06, disturbed M = 0.85, g; = 0.1, t(18) = 0.9199, g = 0.1849). Similarly, the difference of mean values of the Simpson’s Reciprocal 101 Index was not significantly different for undisturbed (M = 12.03, E = 5.38) and disturbed (M = 9.53, S_D = 5.59) forests, 1(18) = 0.8742, g = 0.1965). However, the combination of undisturbed and logged forest sites (M = 0.892, S_D = 0.05) produced significantly higher Simpson’s Index of Diversity than did those burned forest sites (M = 0.796, g = 0.13), 1(18) = 2.401, g = 0.0135. Undisturbed forest sites had significantly higher canopy cover (M = 87.7, _D = 2.7) than did the forest sites disturbed by selective logging and forest fires (M = 80.1, _S_D_ = 7.7), 1(18) = 2.138, p = 0.0232. Undisturbed forest sites also had higher canopy cover (M = 88.6, E = 1.8) than did the forest sites disturbed by forest fire only (M = 76.6, S_D = 11.1), 1(9) = 2.37, p = 0.021. Similarly, undisturbed forests had higher canopy cover (M = 88.6, E = 1.8) than did the forest sites disturbed by selective logging only (M = 81.9, S_D = 2.886), 1(12) = 4.627, p = 0.001. Mean values of fuel load (metric tons per hectare) and litter depth (cm) did not show substantial difference among various types of forest uses. For example, the estimated difference of mean values of fuel load for undisturbed (M = 68.1, §[_) = 42.1) and disturbed forests (M = 60.5, SQ = 36.5) was not significant, _t_(18) = 0.380, p = 0.351. This result showed, however, that variance (standard deviation) is substantial among those forest sites. The greatest fuel loads of approximately 141 and 138 metric tons per hectare were observed in previously logged forests in Mato Grosso and Rond6nia, respectively. As opposed to forest uses, amount of fuel load seemed to vary significantly among the study regions. Study sites located in Rondénia and Mato Grosso (M = 71.1, SQ = 35.8) had 102 higher fuel loads than did those located in Acre (M = 27.9, _S_D = 14.8), t(18) = 2.32, p = 0.016. Similarly, study sites located in Rondénia and Mato Grosso (M = 4.6, S_D = 2.3) had higher litter depth than did those located in Acre (M = 2.1, _S_D = 1.1), 1(18) = 2.157, p = 0.023. The difference of mean of mortality rates of tree species (DBH > 10 cm) for undisturbed (M = 7.3, SD = 3.9) and disturbed forests (M = 15.9, S_D = 15.5) was not significantly different from zero, 1(18) = -1.2163, g = 0.12. Undisturbed and logged forest combined had significantly lower tree mortality rates (M = 7.6, S_D = 4.5) than did those burned forest sites (M = 28.1, SD = 18.2), 1(18) = - 4.064, g = 0.000. Undisturbed and logged forest combined also had lower rates of dead basal area (M = 8.47, _S_D = 5.2) than did those burned forest only (M = 22.7, S_D = 17.2), 1(18) = -2.897, g = 0.000. The difference of mean values of the rate of dead basal area for undisturbed and disturbed forests was not significantly different from zero, 1(18) = -0.9060, g = 0.1885. 3.4.5. Links between forest canopy and further ecological indicators Pearson correlation values among various field measurements that indicate different level of forest disturbances are presented in Table 3.5. Further estimates of forest disturbance indicators based on field measurements are presented in Appendix 07. High negative correlation values were observed between forest canopy cover, tree mortality rate, and dead basal area. These results indicate that tree mortality rate and dead basal area increase when there is a decrease in forest canopy cover. 103 Table 3.5 Correlation matrix among various forest parameters measured in the study sites in the State of Acre, Rond6nia, and Mato Grosso. FC TMR DBA REG REG5 REGI° Fuel Litter load depth SID SRI FC 1 TMR -0.77 1 DBA -0.78 0.93 1 REG 0.03 -0.19 -0.17 1 REG5 0.14 002 -0.01 -0.29 1 REG1o 0.31 -0.24 -0.18 —0.18 0.79 1 Fuel load -0.13 0.28 0.17 -0.27 -0.40 -0.41 1 Litter depth 0.40 -022 -0.17 -0.37 -0.04 -0.08 0.37 1 SID 0.70 -0.74 -0.73 0.37 0.02 0.22 -0.20 0.10 1 SRI 0.36 -0.47 -0.43 0.35 -0.02 0.28 -0.25 -0.19 0.82 1 Pearson correlation is significant at the 0.01 level (1-tailed) for bold values, which represent special interest in this analysis. N= 20 FC = Canopy cover (%) derived from hemispherical pictures; TMR = Tree mortality rate; DBA = Dead basal area; REG = Tree regeneration > 10 cm DBH; REG5 = Tree regeneration < 5 cm DBH; REG10 = Tree regeneration between 5 and 10 cm DBH; SID = Simpson’s Index of Diversity; RSI = Simpson’s Reciprocal Index The Simpson’s Diversity Index showed a high positive Pearson correlation value with forest canopy cover, indicating that tree diversity increases when canopy cover increases. On the other hand, the Simpson’s Diversity Index had high negative Pearson correlation values with tree mortality rate and dead basal area. These results indicate that tree diversity decreases when tree mortality rate and dead basal area increase. Tree mortality rate and dead basal area had high positive correlation. Finally, two size groups (i.e. <5 cm DBH and 5-10 cm DBH) of regeneration tree species had high positive correlation. These results indicate that forest regeneration is not only a process with temporal fluctuations but dependent on the existence of viable tree individuals. 104 3.5. Conclusions The present results showed a substantial increase (~300%) of forest degradation by selective logging and forest fires in the Brazilian Amazon between 1992 and 1999. The total area of forest impacted by these activities was around of 11800 kmz, 18500 kmz, and 35800 km2 in 1992, 1996, and 1999, respectively. Total estimates indicated that at least 52859 km2 of natural forests (1.1% of the entire Brazilian Amazon) were selectively logged and/or burned between 1992 and 1999. From this total, approximately 10000 km2 were deforested by 1999. Selective logging alone was responsible for more than 60% of forest disturbances detected in the studied period and, approximately, 33% and 7% of forest disturbances were due to forest fire alone and forest fire and selective logging combined, respectively. The States of Mato Grosso and Para were affected by approximately 90% of this forest degradation detected using remotely sensed data acquired in 1992, 1996, and 1999 (see the spatial distribution of selectively logged and burned forests detected on maps presented in Appendices 0.12 to 0.17). These amounts of forest disturbances detected in 1992, 1996, and 1999 do not represent, however, annual rates because they did not occur exclusively on these given years. Most of selectively logged forests are detectable on satellite imagery up to a year following logging activities, but none of the disturbed forests should remain detectable more than 2-3 years due to rapid forest regeneration in tropical regions (Stone and Lefebvre, 1998, Sousa Jr and Barreto, 2000). Evidences of burned forests can be even more persistent on 105 satellite data. However, their accurate detection would require multi-annual dataset in order to calculate annual rates of these types of forest disturbances (Souza et al., 2005). Based on this assumption, I used the results of the multi- annual analyses conducted by Matricardi et al. (2005) and the results of the analysis presented in Chapter 2 to estimate the increase of new areas of selectively logged and burned forests, which were then extrapolated to the entire Brazilian Amazon. In the case of selective logging, I used the average relations between total detected and the increase of logging areas from 1992 to 1999 observed by Matricardi et al. (2005) in the Mato Grosso and Rondonia study cases, 39.5% and 91.4%, respectively. Furthermore, Matricardi et al. (2005) assumed that logging activities may persist up to 3 years on satellite imagery and high intensity logging occurred on those Landsat scenes that showed an average of total detected logging areas greater than 100 km2 yr" in 1996 and 1999. Low intensity logging where fewer marketable trees are harvested, lesser infra-structure built, and, consequently, lower forest disturbances, was assumed to occur on Landsat scenes that showed an average of total detected logging areas below 100 km2 yr’ 1 in 1996 and 1999. Finally, the States of Mato Grosso and Rond6nia average relations (39.5% and 91.4%) were assumed to represent Landsat scenes showing high and low intensity logging activities, respectively. For annual rates of burned forest, I used the average relations between total detected and the increase of burned areas from 1992 to 1999 presented in Chapter 2 for the Mato Grosso case study. The results in this case were 41% 106 and 50.4% observed for burned forests and selectively and burned forests combined, respectively. I also assumed that forest fires may persist up to 5 years on satellite imagery and heavily burned forests occurred on those Landsat scenes showing an average of total detected burned forests greater than 20 km2 yr" in 1996 and 1999. Lightly burned forests were assumed to occur on Landsat scenes showing an average of total detected logging areas less than 20 km2 yr" in 1996 and 1999. Based on the Rond6nla case study, an increase of approximately 100% of burned forests was observed from 1992 to 1999 on Landsat imagery. Additionally, field observations showed that lightly burned areas encompassed small forest plots, sparsely distributed within the Landsat path 232 row 067. Very unique site characteristics (i.e. moist microclimate and dense vegetation) may have reduced fire intensity and prevented fire propagation into neighbor forests. Finally, the average relations (41% and 50.4%) were assumed to represent Landsat scenes showing heavily burned forest only and selectively logged and burned forest combined, respectively. Landsat scenes showing less than 20 km2 yr" in 1996 and 1999 were assumed as having an average relation of 100%. Nevertheless, these lightly burned sites represented less than 10% of the total burned forest detected in the studied period and should produce minor impact on final results. Assuming that the average relations previously presented can be extrapolated to a basin-wide scale, the total increase of selectively logged forest only, burned forest only, and selectively logged and burned forests combined in 1992 was at least 2391 kmz, 2883 kmz, and 193 kmz, respectively. These 107 amounts increased to 3951 kmz, 3018 kmz, and 849 km2 by 1996. Following this increasing trend, estimates for 1999 indicated that areas of selectively logged forest only, burned forest only, and selectively logged and burned forests combined expanded to 11767 kmz, 4514 kmz, and 1156 kmz, respectively. These new areas of selective logging and forest fires represent around of 46% of the total disturbed forests detected in 1992 and 1996, and 49% in 1999. These areas were considered to have been previously impacted by selective logging and forest fire and, due to their more severe forest disturbances, were more persistent on satellite imagery. The remaining detected disturbed forests increased from 8401 km2 in 1992 to 8913 km2 in 1998 and 18258 km2 in 1999. The total areas detected and annual rates of selective logging and forest fires are presented in Tables 3.3 and 3.6, respectively. New areas of natural forests impacted by selective logging and forest fires increased 139% and 229% in the period between 1992 and 1996 and between 1996 and 1999, respectively. Matricardi et al. (2007) had estimated rather similar increases of new areas of selective logging only in the same period for the entire Brazilian Amazon. These results support previous reports of increasing trends in degradation of natural forests in the Brazilian Amazon by selective logging activities (Uhl et al., 1997, Nepstad et al., 1998, Stone and Lefebvre, 1998, Souza and Barreto, 2000) and forest fires (Uhl and Buschbacher, 1985, Uhl and Kauffman, 1990, Cochrane and Schulze, 1998, Cochrane, 2001, Cochrane et al., 2004). 108 Table 3.6. Estimated increase of new selectively logged, forests burned, and selectively logged and burned forests in the Brazilian Amazon. Annual increase (km2) Year Logged only (1) Burned only (2) Burned & Total Logged (3) 1992 2,391.0 2,883.6 193.5 5,468.2 1996 3,951.6 3,018.6 649.4 7,619.6 1999 11,767.9 4,514.4 1,156.9 17,439.2 1 Logging average 1 (39. 5%) and average 2 (91.4%) of selective logging increases were estimated for Mato Grosso and Rondonia study cases, respectively. (Matricardi et al. 2005) 2Logged and burned forest average 1 (50. 4%) and average 2 (100%) of burned and logged forests combined were estimated for Mato Grosso and Rondonia study cases, respectively 3Burned forest average 1 (41%) and average 2 (100%) of burned forest“ Increases were estimated for Mato Grosso and Rondonia study cases, respectively. These averages were calculated as total area of forest Showing selectively logged and/or burned forests for the first time divided by the total area of forest wherein selective logging and/or forest fire was detected. Logging averages 1 and 2 were used to estimate new areas of forests impacted by selective logging and forest fire for all Landsat scenes showing total area of selective logging more or less than 100 km2 yr", respectively. The burned forest averages 1 and 2 were used to estimate new areas of forests burned for all Landsat scenes showing total areas of this forest disturbance more or less than 20 km2 yr", respectively. This last procedure was applied to estimate new areas of selective Ioggi_ng and forest fires using the averages 1 and 2. The intensity of forest disturbances is also increasing in the Brazilian Amazon. Formerly logged forests are increasingly been revisited by loggers searching for the second tier economic species as raw material and undisturbed forests became scarcer (Uhl et al., 1997, Matricardi et al., 2005). Matricardi et al. (2005) reported that revisiting logging increased approximately to 7.3% of the total logged forest in the period of 1993-2002. Similar increase (7.1%) of recurrent fires was observed in the studied period in Mato Grosso (see Chapter 2). The study case results support the research conducted by Cochrane and Schulze (1998) who observed that recurrent fire and its intensity are likely to 109 increase because of favorable local environmental created by the previous fire events. Forest disturbances within the limits of protected areas represented an average of 2.9% and 2.8% of the total area of the detected selective logging and forest fire, respectively. The results indicated that such areas have been very effective in constraining these types of anthropogenic activities in Brazilian Amazon. The results also indicated that between 1992 and 1999 the total area detected of selectively logged and burned forests within protected areas increased 2.9% and 4.5%, respectively. This trend of increasing forest degradation within protected areas supports the analysis by Pedlowski et al. (2005) who reported that many conservation units in the Brazilian Amazon have been increasingly been exposed to logging and deforestation activities. Finally, the results of the methods used in this analysis are considered conservative, since, in different circumstances, degraded forests by selective logging and forest fires cannot be detected. Indeed, Matricardi et al. (2005) and Matricardi et al. (2007) observed that very low intensity selective logging cannot be easily detected using remote sensing approaches, nor it may cause substantial environmental impacts on natural forests and on fluxes of carbon dioxide. However, the total areas of natural forests here classified as selectively logged and burned forests represent additional land use types that constitute major forest impacts and have not yet been properly accounted for by conventional remote sensing approaches of deforestation assessment. 110 CHAPTER IV Spatially explicit probabilistic models of forest fire and selective logging in the Brazilian Amazon 4.1. Abstract In this chapter, multivariate probit models of forest fire and selective logging were designed for the Brazilian Amazon. I developed these models using variables that affect the occurrence of forest fire and selective logging throughout the region. Therefore, the effects of each variable on likelihood of forest fire and selective logging were estimated. In spite of the results of a forest fire probit model indicated that distance to deforestation is the most correlated factor to forest fires, a combination of factors (e.g. prolonged water deficit, selective logging, vegetation type, and forest fragmentation) were apparently the more realistic causes of forest fires in the Brazilian Amazon. In apparent opposition to forest fire probability estimates, the selective logging probit model demonstrated that logging activities were not significantly related to distance to deforestation events. In fact, distance to access roads and timber centers were the most significant statically and substantively factors affecting occurrence of selective logging events. The average total timber volume per hectare was significant statistically but not substantively, which indicated that abundance of timber sources was not as important as its accessibility for loggers in the period of analysis. Like forest fire probability, all factors combined (e.g. distance to roads and timber centers, timber volume, vegetation types, land status, etc.) seemed to define chances of selective logging occurrence. Although I could observe some 111 synergistic interactions between selective logging and forest fire, selective logging activities were spatially located predominantly in new frontiers of undisturbed forests, while most of forest fire events occurred in more fragmented forests patches next to older deforestation areas. Finally, field information indicated that the landowner’s desire of converting natural forests into agricultural land may strongly affect forest fire probability. This factor, however, was not included in the forest fire probit model because it is considered a criminal action without previous authorization from the environmental agencies and, therefore, it is very difficult to accurately survey it in the Brazilian Amazon. 4.2. Introduction As already discussed in Chapters 1, 2, and 3, selective logging and forest fire are becoming anthropogenic activities of special concern in tropical regions due they potential impacts both on people and the environment. Various authors have been studying these phenomena in the Brazilian Amazon and the resultant synergistic interaction among them. Uhl and Buschbacher(1985) and Uhl et al. (1991) observed that impacts by selective logging on undisturbed forests can be severe, involving forest canopy damages, dead slash vegetation, and degradation by logging infrastructure such access roads, skid trails, and patios. These forest disturbances can be substantial even upon the occurrence of a very selective timber harvesting event (Frumhoff, 1995). Consequently, forests damaged by selective logging become more susceptible to fires, and fire- maintained agricultural lands work as powerful ignition sources and fire can rapidly spread into adjacent and more flammable selectively logged forests (Uhl 112 and Buschbacher, 1985). Furthermore, forest roads left behind by logging activities provide access to occupation of new frontiers by landless peasants and squatters (Uhl and Vieira, 1989). In addition to forest disturbances by selective logging and deforestation, several other factors might be contributing to increase forest fire in the Brazilian Amazon. Studies conducted by Kuntz and Siegert (1999) and Siegert et al. (2001) indicate that severe drought can be observed during years of climatic events such as El Nino in the Amazon region. Such events substantially increase forest susceptibility to fire (Cochrane, 2001, Laurance and Williamson, 2001, Nelson, 2001). For example, Nelson (2001) reported that area and severity of forest fires varied according to vegetation type in the state of Roraima in which secondary and igapo (low land) forests were the most severely damaged vegetation types during the 1997-98 dry season in that region. Based on that the evidence present in the literature, I conducted a spatiotemporal analysis using probabilistic models to assess probability of selective logging and forest fire occurring in the Brazilian Amazon. To reach this goal, I applied multivariate probit models and variables derived from remotely sensed data. Each variable represented a specific factor potentially affecting the spatial and temporal distributions of selective logging and forest fire throughout the region. I also used multi-temporal datasets for 1992, 1996, and 1999, including variables representing climatic, landscape, and land use characteristics such as vegetation types, water deficits, deforestation, and forest fragmentation. 113 The results of the final probabilistic models substantially improved the current understanding of spatiotemporal distribution of forest fires, selective logging, and their interaction. These results also contribute to improve land use and land cover change modeling, and the development of forest fire control and selective logging monitoring programs by governmental agencies in Brazil. 4.3. Methods 4.3.1. The setting This research focused on tropical rainforests located within the Brazilian Amazon, which encompasses an area of approximately 5 million square kilometers and includes all of the states of Acre, Amapa, Amazonas, Para, Rond6nia, Roraima, and portions of the Mato Grosso, Maranhao, and Tocantins. However, I centered my spatiotemporal analysis of selective logging and forest fire occurrence in a study region (Appendix 0.1) within the Brazilian Amazon where signs of selectively logged and forest fires were most evident in Landsat imagery in 1992, 1996, and 1999 (Appendices C.12 to C17). Therefore, I excluded those areas where these types of human activities were highly unlikely. 4.3.2. Datasets 4.3.2.1. Deforestation dataset A deforestation dataset produced by the Tropical Rain Forest Information Center (http://www.trfic.msu.edu) at the Michigan State University was used in this study. This dataset involves a multi-annual classification of 229 Landsat scenes covering the entire Brazilian Amazon. Landsat images were individually classified into seven thematic classes: forest, deforestation, regrowth, cerrado, 114 cloud, cloud shadow, and water using unsupervised image classification procedures. Three mosaics of the Landsat scenes available for the entire Brazilian Amazon for 1992, 1996, and 1999 (Appendix D.2) were used to perform the spatially explicit probabilistic models of fire and selective logging in the study region, and details of the deforestation dataset are presented in Table 4.1. Table 4.1 Deforestation dataset characteristics Dataset Features Format Spatial Period of Projection resolution Analysis Land use Forest, Arc/Info 30m x 30m 1992, Sinusoidal and land deforestation, vector 1 996, projection, cover secondary and and Datum and mosaic regrowth, grid 1 999 Spheroid cerrado, WGS84 clouds,and shadows 4.3.2.2. Selective logging dataset As previously addressed in Chapter 2 and 3, selectively logged forests were not included as a land use class in the deforestation dataset produced by the TRFIC at MSU because more sensitive remote sensing techniques are required to accurately detect and map their presence. Therefore, selectively logged forests were detected and mapped using a semi-automated (texture algorithm) technique and Landsat band 5 to detect log landings (i.e. log storage patios) and, subsequently, variable buffer zones were applied (180 and 450 meters) around patios to estimate the size of areas affected by selective logging. Following Matricardi et al.(2007), visual interpretation was used to map selectively logged forests with visible canopy disturbance on Landsat images. 115 The combination of these remote sensing approaches showed 92.9% and 0.82 of overall accuracy and overall kappa statistic, respectively. The selective logging dataset available at Global Observatory for Ecosystem Services (GOES), Michigan State University included three multi- temporal mosaics of selective logging of the entire Brazilian Amazon (Table 4.2). Table 4.2 Selective Logging dataset characteristics Dataset Classification Format Spatial Period of Projection Features resolution Analysis Selectively Binary classes Arc/Info 30m x 30m 1992, Sinusoidal, logged forest (1 if selectively grid 1996, WGS84 GIS layers logged, 0 and Datum and (mosaic) otherwise) 1999 Spheroid Such mosaics included a binary classification of natural forests (1 if selectively logged, 0 if othenlvise) for up to 38 Landsat scenes throughout the Brazilian Amazon for 1992, 1996 and 1999 The present study also included the selective logging mosaics for 1992, 1996, and 1999 produced by Matricardi et al. (2007) (Appendices C14, C15, and 0.16) 4.3.2.3. Thematic maps The present analytical effort included thematic maps of urban areas, road network, protected areas, vegetation types, timber centers, and state borders in the Brazilian Amazon. The urban area, road network, and state maps were digitized by SIVAM (2004) from datasets produced by the Brazilian Institute of Geography and Statistics (IBGE), derived from field surveillance and remotely sensed data. The vegetation map was compiled and digitized by SIVAM (2004) from dataset produced by the RADAMBRASIL Project in 1980 (Appendix 03). 116 The map of timber centers in the Brazilian Amazon was composed of timber center locations reported by Lentini et al. (2003), and the map of urban areas produced by SIVAM (2004). The timber center locations were defined based on the spatial distribution of 1190 saw mills surveyed by the Amazon Institute of Man and Environment — IMAZON throughout the Brazilian Amazon in 1998. The identification of city location for each timber center was based on Lentini et al. (2002) and their geographic location was plotted accordingly on the map of urban areas (Table 4.3). Table 4.3. Description of the thematic maps Dataset Features Format Original Projection Source scale Map of Lines and table Arc/Info Derived Geographic, SIVAM road of road types coverage from Datum IBGE network (paved, and *.dbf Landsat SAD69 unpaved, imagery, 30 access, etc.) m spatial resolution Map of the Polygons, arcs, Arc/Info 1:250,000 Geographic, SIVAM Amazon table of the coverage Datum IBGE States State borders and *.dbf SAD69 Map of Polygons, arcs, Arc/Info 1:250,000 Geographic, SIVAM urban table of city coverage Datum IBGE areas locations and and *.dbf SADS9 urban areas Map of Polygons, arcs Arc/Info 1:250,000 Geographic, ISA protected and table coverage Datum IBAMA areas and *.dbf SADGQ Map of Polygons, arcs, Arc/Info 1:250,000 Geographic, SIVAM vegetation table of coverage Datum IBGE vegetation and *.dbf SAD69 types Timber Points and Arc/Info 1:250,000 Geographic, IMAZON centers tables coverage Datum and *.dbf SA069 The road network map included different road types, which mostly included official roads constructed by the federal, state and local governments. 117 The road classification includes paved road, unpaved, secondary roads, and access roads. Logging roads and trails were not included. The state map included borders of all states within the Legal Brazilian Amazon. The map of urban areas included identification, location and administrative classification (i.e. capital, city, and village) of all urban areas in the Amazon region for 1999. Indigenous land, conservation unit classification (i.e. parks, ecological reserves, extractive reserves, national and state forests, etc), and military areas were included in the protected areas map. Appendix D.5 shows a composite map of road network, protected areas, and timber center location. Finally, the vegetation map included several vegetation types and sub- types. The present analysis included 6 classes of forest types: dense, open, semi-deciduous, deciduous, transitional, and pioneer forests. By 1999, approximately 27%, 23%, 23%, 21% of the study area was covered by dense forest, open forest, transitional forest, and cerrado (savannah), respectively. Therefore, tropical rainforest was the predominant vegetation in the study region covering 73% of its territorial area by 1999. All these thematic maps were used to support the spatial analysis of forest degradation by selective logging and forest fires in the Brazilian Amazon. 4.3.2.4. Timber volume in the Brazilian Amazon In the 1970s the RADAMBRASIL Project conducted a forest inventory that included tree species identification and measurements (i.e. basal area and volume) within thousands of sample units throughout the Brazilian Amazon. In this study, I used a dataset digitized by SIVAM (2004) containing the geographic 118 location and the total timber volume of tree species measured within 57,971 sample units generated by the RADAMBRASIL Project. In addition, a variogram model was created by using these sample points, and ordinary kriging using the values derived from this model was run in ArcGlSTM. The variogram model used for ordinary kriging had an exponential curve, with a nugget of 2182.8, a range of 3,076,600, and a partial sill of 4460.1. As a result, a map of the timber volume per hectare was created for the Brazilian Amazon and then converted into a grid (Appendix 05). 4.3.2.5. Water balance Water balance is a good measure of the moisture available in a terrestrial ecosystem and, ultimately, can be a good indicator of forest fire flammability. The water balance dataset used in this analysis was generated by (Willmott, 1999) based in a modified procedure developed by Thornthwaite and Mather in 1955. Basically, the calculation procedure for this model included multiple variables such as: soil water-holding capacity, the gridded average-monthly precipitation, evapotranspiration, and temperature. The average water balance datasets for 1992, 1996 and 1999 were then used to identify areas with water deficit during the dry season7 in these given years. Appendix D.6 shows the water balance for the Brazilian Amazon during the dry season (May to September) in 1999. 7 The dry season is defined as a time period from May to September, when a prolonged low precipitation and high temperature can be observed in the Amazon region. The dry season for the Northern Amazon, however, normally occurs from January to March. 119 4.3.3. Forest Fragmentation Skole and Tucker (1993) introduced the concept of fragmented forests in the context of tropical deforestation studies. Deforestation was previously addressed through a binomial classification of forest and non-forest. These authors observed that forest fragmentation could affect larger areas than deforestation itself, especially in the context of the Brazilian Amazon. In their ground-breaking research, Skole and Tucker (1993) defined fragmented forests as forested areas smaller than 100 hectares surrounded by deforested lands, and edge effects as a series of ecological responses affecting a buffer zone distant up to 1 km from adjacent deforested areas. Concepts drawn from Landscape Ecology have also been applied to enhance the understanding of the ecological implications of anthropogenic activities on forest ecosystems (Turner et al., 2001). Accordingly, I used two of the patch-based measures (patch area and fractal dimension) of landscape patterns proposed by Skole and Tucker (2001) to assess the presence of distinct levels of forest fragmentation in the study area. Patch area can be used to display the frequency distribution of number of patches and patch Size. Therefore, a high frequency of small patch size is a good indicator of forest fragmentation intensity, although it disregards the shaping of the patches. Conversely, patch shape can be a good indicator of temporal changes in landscape patterns. For example, small forest patches tend to have simpler shapes than larger ones due to human activities and natural boundary effects, 120 respectively. Thus, fractal dimension is a useful indicator of shape complexity for patches of different sizes (Turner et al., 2001). _ In(A) " In(P) + ln(k) (1) where d = fractal dimension, A = area of each patch, P = perimeter of each patch, and k = 0.25 constant value if the actual patch perimeter is used to estimate P. By applying the equation 1, fractal dimension can depict the shape of each forest patch that may range from 1.0 to 2.0 for a straight line and a circle or square forest patch, respectively. These two patched based measurements were applied in the study region using land use and land cover classification maps from 1992, 1996 and 1999. I used log transformed of path size (m2) in order to minimize the effects of very large forest patches, and fractal dimension was applied using the equation 1. The constant k = 0.25 was applied to estimate the fractal dimension of forest patches. Forested areas are shown in Appendix 02. 4.3.4. Modeling forest fie and selective logging probabilities in the Amazon Spatial pattern of selective logging and forest fire, their impacts and interactions with other land use and socioeconomic variables were assessed using two multivariate Probit models. The Probit is a binary response model, which implies that the estimated probabilities will range between 0 and 1. This model uses the standard normal cumulative distribution function and its use is most indicated when the dependent variable is discrete and the partial effect of any independent variable is potentially not constant (Wooldridge, 2000). 121 The probit models were used to identify the factors influencing the probability of selective logging and forest fire occurrence throughout the study region within the Brazilian Amazon based on their spatial distribution, local biophysical characteristics, and socioeconomic factors. According to (Wooldridge, 2000), the probit model can be defined as: v*=ito+xis+s. v=1iy*>01. (2) where y* is the unobserved or latent variable (in this study, a pixel representing forest fire) that satisfies a normal, homoskedastic distribution with a linear conditional mean; x is a vector of independent variables; 8 is a vector of unknown coefficients; and § is an independently distributed error term assumed to be normal with zero mean and constant variance 02. The indicator function requires that observations take 1 as their value if the event (forest fire) is true, and 0 if othenlvise. Therefore, y=1ify*> 0, and y= 0 if y* .<. 0. Based on this approach, the probability of forest fire and selective logging in the study region can be defined using equation 3: P0! = 1 IX) = P8" > OIX) = P(8 > -XB|X) = $049 (3) where, (.) is the standard cumulative normal distribution function (cdf); x is a vector of independent variables, and B is a vector of unknown coefficients. 4.3.4.1. Forest fire conceptual model Previous studies have shown that forest fire is a growing problem in the Brazilian Amazon due to different factors such as: the sprawl of ignition sources 122 from fire-managed agricultural lands Uhl and Buschbacher (1985) and the increasing forest flammability (caused by greater fuel availability and drier microclimates) as natural forests become more fragmented Cochrane(2001) and Cochrane (2004) and disturbed by deforestation and selective logging activities (Uhl and Buschbacher, 1985, Uhl and Kauffman, 1990, Holdsworth and Uhl, 1997, Cochrane et al., 2004). Environmental conditions may also substantively increase forest flammability. For example, Uhl and Buschbacher (1985), Nepstad et al. (1999), Houghton et al. (2000) , and Nelson (2001) reported that fires are more likely during years of prolonged drought. Many authors (Uhl and Buschbacher, 1985, Uhl and Kauffman, 1990, Holdsworth and Uhl, 1997, Cochrane and Schulze, 1998, Cochrane, 2001, Nelson, 2001, Cochrane et al., 2004) have observed that agricultural land is a major ignition source for forest fires in the Brazilian Amazon. In addition to that, I could observe during the fieldwork that fires frequently occur along roads and, consequently, one may need to take into account the importance of transportation networks as ignition sources. I could not find evidences, however, of lightning strikes as important ignition sources of forest fire. This finding is probably explained by the fact that most lightning strikes occur during the rainy season when forests are too moist to allow fire ignition. Therefore, I hypothesized that any forest fires observed in this study would be human-driven whether accidentally or intentionally. In addition to the ignition sources of fire, forests are becoming increasingly fragmented and, hence, more susceptible to fires. Consequently, selective 123 logging which has been reported as a major source of forest disturbances in the Brazilian Amazon (Nepstad et al., 1999, Skole et al., 2004, Asner et al., 2005, Matricardi et al., 2007) also is deemed as a cause of increased forest fire (Uhl and Buschbacher, 1985, Uhl and Kauffman, 1990, Holdsworth and Uhl, 1997, Cochrane and Schulze, 1998, Nepstad et al., 1999, Cochrane, 2001, Nelson, 2001, Cochrane et al., 2004). Additionally, small forest patches and larger forest edges left behind by the deforestation contribute substantially to forest fragmentation (Skole and Tucker, 1993, Cochrane et al., 2004, Skole et al., 2004). Once fragmented, tropical forests become more susceptible to fires (Cochrane, 2001, Cochrane et al., 2004). Water balance is an important environmental factor that may contribute to increase forest fire susceptibility in tropical regions (Cochrane, 2001, Laurance and Williamson, 2001, Nelson, 2001). Forest fires are more likely to occur in tropical regions during the dry season, when precipitation is very low (Uhl and Buschbacher, 1985, Houghton et al., 2000) and during years of extreme moisture deficit and prolonged drought , where even undisturbed forests may become flammable (Nepstad et al., 1999, Nelson, 2001). For example, a prolonged water deficit such as the extreme drought observed during year of climatic events such as the 1997-98 El Nir‘io (Kuntz and Siegert, 1999, Siegert et al., 2001) substantially increased forest flammability in the Amazon region. The forest fire conceptual model was based on the assumption that three major factors may increase the probability of forest fire in the study region: ignition sources, forest disturbances, and environmental conditions. I created a 124 vector of independent variables, which included the previously discussed biophysical and socioeconomic factors that affect forest susceptibility to fire. First, a dummy variable was created for the land status (1 if within protected areas, 0 if othenlvise). It is expected that the land status of protected areas (e.g. ecological reserves, indigenous land, extractive reserves, national parks) should be a legal barrier for deforestation and selective logging activities (Pedlowski et al., 2005) and, therefore, a grid cell (unit of observation) representing forest fire is less likely to occur within their territorial borders. Dummy variables for each year of selective logging (1 if logged, 0 if otherwise) also were created. It is expected that selectively logged forests are more susceptible to fire than undisturbed forests because of the canopy degradation caused by logging lead to a rapid decrease moisture and humidity in logged forests (Uhl and Kauffman, 1990). Subsequently, I created two continuous variables based on the Euclidean distances to agricultural lands (i.e. deforestation) and roads, which estimated the proximity of grid cells representing burned and non-burned forests to roads and deforested areas. Another continuous variable was created to represent the water deficit during the dry season of each year of analysis. As previously discussed, it is expected that forests under prolonged water deficit would be more vulnerable to fire than those under moisture conditions. Two other continuous variables (logarithm of forest patch size and fractal dimension) were created to represent landscape fragmentation, since smaller forest patch sizes and lower values of fractal dimension are likely to be more fragmented, therefore, more susceptible to fire. 125 I also created a set of dummy variables to represent vegetation factors, assuming that forest fires are more likely to occur in drier microclimate observed in deciduous, semi-deciduous, and transitional forests than in moisture microclimate observed in dense and open forests. Finally, dummy variables were created to represent each state within the study region, which were intended to capture potential variations at state level due to different environmental legislation and law enforcement capabilities. As previously presented in Chapter 3, the bulk of selective logging and forest fire activities were detected in the states of Mato Grosso, Paré, and Maranhéo in 1992, 1996, and 1999. These states are located within the so-called Arc of Deforestation created by the Brazilian Institute of Environment and Renewable Natural Resources- IBAMA as a priority region for forest fire control and prevention in the Brazilian Amazon (IBAMA, 2007). Based on that, I tested the vector of the following independent variables (x) for the Probit model described in Equation 2: Protected areas (1 if within protected areas, 0 if otherwise) Proximity to agricultural lands (deforestation) (km) Proximity to agricultural lands squared Proximity to roads (km) Proximity to roads squared Logging in 1999 (1 if selectively logged in 1999, 0 if otherwise) Logging in 1996 (1 if selectively logged in 1996, 0 if othenlvise) Logging in 1992 (1 if selectively logged in 1992, 0if otherwise) Water deficit (1 if water deficit persisted 2 5 months, 0 if otherwise) Forest patch size (In transformed area) Fractal dimension (1 to 2) Vegetation type 1 (1 dense forest, 0 if otherwise) Vegetation type 2 (1 open forest, 0 if othenlvise) Vegetation type 3 (1 semi-deciduous forest, 0 if otherwise) Vegetation type 4 (1 deciduous forest, 0 if otherwise) Vegetation type 5 (1 transitional forest, 0 if otherwise) OOOOOOOOOOOOOOOO 126 o Vegetation type 6 (1 pioneer forest0 if otherwise) 0 Temporal variable 1 (1 if forest was burned in 1999, 0 if othenrvise) 0 Temporal variable 2 ( 1 if forest was burned in 1996, 0 if otherwise) The control variables were indexed to a time scale (temporal variables) in the model. Thus, the interaction between time and other variables was assessed, which contributed to explain spatiotemporal changes of forest. Additionally, potential interactions between forest fires and very large distance from agricultural lands and roads (ignition sources) were also considered. This procedure required creating two new variables, distances to deforested areas and roads squared, which represented spatial patterns of forest fires geographically located at large distance from deforestation and roads. 4.3.4.2. Selective logging conceptual model A multi-temporal assessment of selective logging in the Brazilian Amazon conducted by (Matricardi et al., 2007) showed that selectively logged forests increased more than 336% between 1992 and 1999. The vast majority of these anthropogenic activities were observed within the states of Para and Mato Grosso (Matricardi et al., 2007) and the logging industrial centers were clustered along major Amazon transportation axis (Nepstad et al., 1999, Lentini et al., 2003, Lentini, 2005). (Matricardi et al., 2007) also speculated that some biophysical and socioeconomic factors such as raw material for saw mills, environmental law changes occurred in 1996, and extreme droughts, might have contributed to increase intensity and area of selective logging. Indeed, (Uhl et al., 1997) reported that loggers were increasing both volume and number of tree species harvested in more mature logging regions in which timber products are 127 becoming scarcer. As in the case of forest fires, given their legal status, protected areas also are deemed as offering a barrier for logging activities (Pedlowski et al., 2005). In this case, although the raw material may be abundant and economically viable, it is not legally accessible. Therefore, it was assumed for the selective logging conceptual model that land legal status, raw material availability, transportation networks, and the geographic locations of the timber centers were the major factors driving loggers over natural forests. A dummy variable was created for the land status (1 if within protected areas, 0 otherwise). A grid cell (unit of observation) representing selective logging within protected lands is less likely to be observed. Dummy variables for each year of selective logging (1 if logged, 0 otherwise) also were created. (Matricardi et al., 2007) observed that selective logging substantially increased in area and intensity in Brazilian Amazon, growing approximately 73% and 345% in 1992-96 and 1992-99 periods, respectively. Three continue variables were created to measure selective logging proximity to logging centers, roads, and deforestation. I expected that loggers have to operate at certain buffer distances from logging centers due to the transportation costs and, therefore, selective logging areas would tend to decrease as distance to logging centers increase. I also assumed that saw mills can not be easily relocated closer to sources of raw material because they are strongly attached to the consumption markets, major transportation axis, and labor and electricity availability. Similarly to logging centers, it was expected that undisturbed forests closer to the road networks and previous deforestation are 128 more accessible and, therefore, more likely to be selectively logged than those located at larger distance from access roads and agricultural lands. An additional continue variable was created to represent timber volume (m3/ha. In this case, I assumed that loggers are also attracted by the amount of timber volume (ma/ha) observed in undisturbed forest throughout a given area of interest. Finally, a set of dummy variables was created to represent vegetation factors, assuming that marketable tree species vary according to forest type and, therefore, some forest types should be more attractive for loggers than others. Based on these assumptions, I tested the vector of the following independent variables (x) using the Probit model described in Equation 2 for selective logging: OOOOOOOOOOOOOOOOOO Protected areas (1 ifwithin protected areas, 0 if otherwise) Proximity to agricultural lands (deforestation) (km) Proximity to agricultural lands squared Proximity to roads (km) Proximity to roads squared Proximity to timber centers (km) Proximity to timber centers squared Timber volume (m3 ) Forest patch size (In transformed area) Fractal dimension (1 to 2) Vegetation type 1 (1 if dense forest, 0 if otherwise) Vegetation type 2 (1 if open forest, 0 if otherwise) Vegetation type 3 (1 if semi-deciduous forest, 0 if otherwise) Vegetation type 4 (1 if deciduous forest, 0 if otherwise) Vegetation type 5 (1 if transitional forest, 0 if othenNise) Vegetation type 6 (1 if pioneer forest, 0 if otherwise) Temporal variable 1 ( 1 if selectively logged In 1999, 0 if otherwise) Temporal variable 2 ( 1 if selectively logged In 1996, 0 if otherwise) In the selective logging probit model the control variables were also indexed to a time scale (temporal variables), to allow the assessment of selective logging spatiotemporal changes. Finally, I created three variables (distances to 129 deforested areas, roads, and timber centers squared) to observe the spatial distribution of selective logging at very large distances from logging centers, deforested areas, and road network. 4.3.4.3. Data sampling As previously indicated, the present analytical exercise focused on a study region where evidences of selective logging and forest fire have been observed using remotely sensed data, including 'portions of the states of Para, Mato Grosso, Tocantins, Acre, Rondbnia, and Maranhéo. This option helped to improve the sampling process and the statistical model performance. Analyses involved datasets for 1992, 1996, and 1999, which is the most recent year of mapping of forest fire and selective logging available for the Brazilian Amazon. In this spatially explicit probabilistic analysis of selective logging and forest fires, a stratified random sampling was applied to collect spatial data from point locations. First, a vector of 5x5 km grid cell size was located evenly over the study region. Subsequently, one point was randomly located within each 25 km2 grid cell (Figure 4.1). The pixel was used as the unit of observation and, therefore, a unique value of the dataset was collected for each point of the sampling grid to represent forest fire (1 if burned, 0 if othenlvise) and another to represent selective logging (1 if logged, 0 if otherwise) (Appendix D.1). Similarly, a pixel value was collected for each independent variable and point location. 130 55:: T—T'l Rand” . I sampling 5 0 5 10 15 20Km j _ , points Figure 4.1 Stratified random sampling used to collect spatial data for the probit model of forest fire and selective logging in the study region. This stratified sampling procedure was designed to reduce the effects autocorrelation in the dataset (Anselin 2002, Arima et al. 2007). The random distribution of points within a regular sampling network can reduce effects of potential coincidence between spatial patterns of landscape and sampling points (Burrough, 1998). Stratified and random sampling combined can minimize statistical biasness of as given model (Burrough, 1998, Anselin, 2002) and the error term in the probit models due to spatial autocorrelation in the data population (Chomitz and Gray 1996, Arima et al 2007). 131 4.4. Results and Discussion 4.4.1. Forest fire probabilistic model The analysis of forest fire dataset showed that although forest fire observation was relatively rare (unconditional probability of forest fire = 0.77%) in the study region, encompassing more than 1.7 million km2 of tropical rainforests by 1999, it has increasingly become a socioeconomic and environmental concern in the last decades. The statistical significances of the previously discussed factors that affect forest fire probability were estimated using a probit regression model (Table 4.4). The estimated model predicts that forest fires are inversely related to distance to deforestation (agricultural lands). The probability of forest fires proved to be significant both statistically and substantively. Forest fires increased as distance to deforestation decreased. For example, by decreasing distance to deforestation areas from 10 to 0 km would increase forest fire by 42%. The predicted non-linear effect of distance to deforestation in the probability of forest fire is presented in Figure 4.2. 132 Table 4.4. Probit regression analysis results of forest fire Variables and Constant Coefficient Rob. St. P > |z| dF/DX Error Protected areas ( 1 if yes, 0 otherwise) -0.1955 0.0681 0.004 -0.00002 Distance to deforested areas (km) -0.1594 0.0144 0.000 -0.00002 Distance to deforested areas squared 0.0011 0.0001 0.000 0.0000001 Distance to roads (km) -0.0294 0.0043 0.000 -0.000003 Distance to roads squared 0.0002 0.00003 0.000 0.00000002 Selectively logged 1999 (1 if yes, 0 otherwise) 0.7075 0.0567 0.000 0.0004 Selectively logged prior to 1999 (1 if yes, 0 otherwise) 0.5716 0.0853 0.000 0.0002 Water deficit between May and September 0.0021 0.0008 0.011 0.0000002 Patch size (log area m2) -0.0113 0.0025 0.000 -0.000001 Fractal dimension ( 1 to 2) -0.2445 0.0444 0.000 -0.00003 Vegetation type: (omitted Pioneer) Dense forest 0.2033 0.0970 0.036 0.00003 Open forest 0.4145 0.0969 0.000 0.00007 Semi-deciduous forest 0.4337 0.1591 0.006 0.0001 Deciduous forest 0.0210 0.1429 0.883 0.000003 Transitional forest (Forest/Savannah) 0.4555 0.0936 0.000 0.00009 State: (omitted Acre) Para 0.9668 0.2224 0.000 0.0002 Maranhao 0.7751 0.2276 0.001 0.0005 Tocantins 0.3608 0.2517 0.152 0.0001 Mato Grosso 1.0190 0.2224 0.000 0.0005 Rondbnia 0.1016 0.2342 0.664 0.00001 Year: (omitted 1992) 1999 0.5476 0.0458 0.000 0.0001 1996 0.3067 0.0474 0.000 0.00005 Constant -2.8753 0.2439 0.000 Log likelihood = 418839944; Pseudo R2 = 0.2517; n= 144,793 I also estimated the effect of distance to deforestation in quadratic form. As opposed to the estimated parameter of the level term, the squared term was positive indicating that probability of forest fires eventually increases as distance to deforestation increases at very large distances from deforestation. Indeed, I could observe some isolated forest fires in the study region, geographically located away from deforestation areas, which could be associated with selective logging activities. 133 Probabiliy 0.50 0.45 0.40 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0.00 —<>— Forest Fire _;A§—__ -__- __ ____E -___\.. WW 3%- _ ___ -2 \ Av. \ _,_. \ _v a i \ E,____ __ ___\\ _ \ ..._. _ _ _u _ ___E.-\ \ _._- \ ,, \ \ _.___ _ E _E \ \ 0 2 4 6 8 10 12 14 Proximity to deforestation (km) Figure 4.2. Probability of forest fire with respect to distance to deforestation forest fire occurrence is inversely related to distance to roads. By decreasing distance to roads from 50 to 0 km, forest fires would increase 7%. The predicted non-linear effect of distance to roads in the probability of forest fire is presented Similarly to distance to deforestation, the estimated model predicts that in Figure 4.3. The effect of distance to roads in quadratic form is positively related to forest fires, indicating that probability of forest fires eventually increases as distance to roads increases at very large distances from roads. It is likely that this type of spatial pattern of forest fire occurs during logging operations in new timber sources located at large distance from roads. 134 0.08 0.07 - 0.06 — 0.05 - 0.04 0.03 . 0.02 ~ ~— 0.01 1 0 4 8121620242832 3640444852 56 60 Proximity to roads (km) —+—- Forest fire I Probability Figure 4.3. Probability of forest fire with respect to distance to roads The water deficit observed in the study region significantly contributed to increase the likelihood of forest fires at 95% probability. The direct effect is that higher water deficit level increases forest flammability. For example, by increasing the water deficit from 0 to 200 millimeters during the dry season (May to September) forest fire likelihood would increase 2.5%. The predicted effect of water deficit in the forest fire likelihood is presented in Figure 4.4. 135 0.045 0.040 ‘ 0.035 l :E‘ 0.030 5 0.025 W ,7, g +ForestfiEI 9 0.020 ‘7 T ’ LL 0.015 0.010 0.005 0.000 0 20 40 60 80 100120140 160 180 200 I Water Deficit (mm) Figure 4.4. Probability of forest fire with respect to water deficit from May to . *4 September The model predicted that the effect of an increase in forest fragmentation was significantly related to forest fires. The results showed that the applied measurements of forest fragmentation (forest patch size and fractal dimension) are significant explanatory variables, because the average probability of forest fires increased by 1% and 2% as fractal dimension decreased from 2 to 1 and forest patch size decreased from 533,000 km2 to 1 kmz, respectively. These increases in absolute probabilities might be considered small in absolute terms, but they are relatively high considering that the unconditional probability of forest fire is 0.77% in the study region. The predicted effect of forest patch size and shape (fractal dimension) in the probability of forest fire is presented in Figure 4.5. 136 Fractal dimension 1 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2 0.040 I I I I l l I I I I I I l 1' l I I I i l 0.035 0.030 - 0.025 - Vi—a—iPiatch Size 0.020 - Probability 1+ éhepe 0.015 0.010 - 0.005 - 0000 ALL]!ll'llllllllllllllllltgllgllllllglllll 0481216202428323640 Log of forest patch size Figure 4.5. Probability of forest fire with respect to forest patch size and shape Meanwhile, selective logging directly affects forest susceptibility to fires. When compared to undisturbed forests, newly and previously detected selective logging areas significantly increased the chance of fire 3.4% and 2.7%, respectively. Selective logging contributes to increase canopy openness and decrease moisture (Uhl and Kauffman, 1990), and hence, higher forest flammability. In addition to selective logging effects, probability of forest fires was 1% greater outside of protected areas than inside of them. This result supports, at least temporarily, the assumption that environmental laws and conservation policies for protected areas has been successfully applied in the Brazilian Amazon, contributing to impede or slow anthropogenic activities (e.g. forest fires) Most of the vegetation dummy variables were statistically significant. Open, semi- 137 deciduous, and transitional forests with 2% of likelihood of forest fires were the most fire-prone forest types by holding all other independent variables fixed at mean value. Dense forest, with 1% of likelihood of forest fires was the least fire prone forest type at 95% probability. Deciduous forest was not statistically different from the omitted forest type (pioneer vegetation). These results show that dense forest is the predominant and least fire prone vegetation type in the Brazilian Amazon region. However, open and transitional forests become of special concern because they were two-fold more likely to fire than dense forest, and, combined, they cover approximately 46% of the study area. The predicted effect of forest types, state political-administrative peculiarities, selective logging, protected areas, and temporal variables on the probability of forest fire is presented in Figure 4.6. The state dummy variables for Rondonia and Tocantins were not statistically different from the omitted state (Acre) in terms of forest fire probability. The dummy variables for Para, Maranhao, and Mato Grosso were both statistically and substantively significant. Mato Grosso has 5.7% greater chance of experiencing fire than the omitted state, while Para and Tocantins have 5.4% and 4.4% likelihood of fire, respectively. These results show that Mato Grosso, Para, and Tocantins are the most fire-prone states in the Brazilian Amazon by holding all other factors constant at mean value. However, the extent of the “arc of forest fire” as defined by the present study does match perfectly the arc of deforestation defined by (IBAMA, 2007). It can be hypothesized that 138 potential differences in state environmental policies and legislation might be affecting forest fire likelihood in the Brazilian Amazon. Probabiity [El Para Mato Grosso ‘ I Open forest ’El Transitional ‘ I Logged by 1999 ’IYear1996 E] Maranhao Tocantins ‘ El Rondonia I Dense forest ‘ I Semi—Deciduous I Deciduous Outside of protected areas I Inside of protected areas . . I Logged by 1996 I Year 1999 , l T T T 7 TTT l Figure 4.6. Probability of forest fire with respect to forest types, states, selective logging, protected areas, and year of analysis Finally, the multi-temporal dummy variables proved to be statistically significant. The year 1999 and 1996 had 3.4% and 2.6% greater chance of experiencing fire than the omitted year (1992). These results contribute to explain the temporal changes of forest fires which showed to be consistently and significantly increasing along the period of analysis. 4.4.2. Selective logging model Based on the selective logging dataset the unconditional probability of selective logging is 1.15% for the study region, which encompassed more than 1.7 million km2 of tropical rain forests by 1999. Additionally, the statistical 139 significances of various factors that affect selective logging probability were estimated using a probit regression model. The results of probit regression analysis of selective logging are presented in Table 4.5. Table 4.5. Probit regression analysis results of selective logging Rob. Variables and Constant Coefficient St. P > lz| dF/DX Error Protected areas ( 1 if yes, 0 otherwise) -0.3168 0.0486 0.000 00001 Distance to deforested areas (km) 0.0051 0.0132 0.697 0.000003 Distance to deforested areas squared -0.0017 0.0009 0.076 -0.0000009 Distance to roads (km) -0.0383 0.0031 0.000 000002 Distance to roads squared 0.0003 0.0000 0.000 0.0000001 Distance to timber center (km) -0.0058 0.0006 0.000 -0.000003 Distance to timber center squared -0.0000004 0.0000 0.873 00000000002 Timber volume (m3/ha) 0.0009 0.0004 0.031 0.0000005 Vegetation type: (omitted Pioneer) Dense forest 0.4229 0.1054 0.000 0.0003 Open forest 0.3101 0.1106 0.005 0.0002 Semi-deciduous forest 0.2576 0.1754 0.142 0.0002 Deciduous forest -0.0714 0.1596 0.655 -0.00004 Transitional forest (Forest/Savan nah) 0.6567 0.1071 0.000 0.0008 State: (omitted Acre) Para 0.9108 0.1948 0.000 0.0008 Maranhao 1.2005 0.1980 0.000 0.007 Tocantins -0.4176 0.3580 0.243 -0.0001 Mato Grosso 0.9233 0.1940 0.000 0.001 RondOnia -0.1841 0.2086 0.378 -0.00008 Year: (omitted 1992) 1999 0.6677 0.0297 0.000 0.0007 1996 0.2478 0.0323 0.000 0.0002 Constant -3.1936 0.2251 0.000 Log likelihood = -6947.22 ; Pseudo R2 = 0.236; n= 144,793 Based on the model results, I estimated the effect of distance to deforestation in linear and quadratic forms. As opposed to the forest fire probit model, the selective logging probit model estimated that neither the parameter of the level term nor the squared term were statistically significant, indicating that distance to deforestation has no effects in probability of selective logging. The estimated model predicted that selective logging is inversely related to distance 140 to roads and, therefore, selective logging increases as distance to roads decreases. Probability of distance to roads proved to be statistically significant. For example, a decrease in distance to roads from 30 to 0 km would increase selective logging by 2.8%. Similarly, selective logging is inversely related to distance to timber centers. The probability of distance to timber centers was also statistically significant. These results show that natural forests become less attractive to loggers if they are obligated to move away from roads and logging centers to harvest timber. The predicted non-linear effect of distance to roads and logging centers in the probability of selective logging is presented in Figure 4.7. Distance to roads (km) 0 3 6 9 121518212427 303336394245 0035 l ‘l llllAilli‘i l‘ l . TIIII’ITIIIIIITIIIIIIIIIIIIII‘ITT 0.030 r 0.025 T 0.020 -- EQands 0.015 _ + Timbericentersg Probability 0.010 -~ 0.005 ~ IlllllllllillllllTIII i , v 0 21 42 63 84 105126 147 168 189 210 Distance to timber centers (km) Figure 4.7. Probability of selective logging with respect to distance to roads and timber centers Meanwhile, I also estimated the effect of distance to roads and logging centers in quadratic form. As opposed to the estimated parameter of the level 141 term, the squared term of distance to roads was positive indicating that probability of selective logging eventually increases as distance to roads increases at very large distances from roads. This supports the assumption that loggers, although reluctantly, could direct their attention toward undisturbed forests geographically located farer away from existing road networks if timber sources become too scarce in those forests close to the road network .The estimated parameter of the squared term of distance to timber centers was not statistically significant, which indicate no effect of distance to timber centers at very large distances from saw mills in the probability of selective logging occurrence. The model predicted that the effect of an increase in timber volume was positively related to selective logging. The results showed that timber volume is significant at 95% probability, with the average probability of selective logging increased by 0.1% as timber volume increased 100 m3. Again, although such increases in absolute probabilities might be considered small in absolute terms, they are considerably high given that unconditional probability of selective logging is 1.15% for the entire study region. The predicted non-linear effect of timber volume in the probability of selective logging is presented in Figure 4.8. 142 0.010 0.009 —~ — T T V 0.008 0.007 0.006 0.005 0.004 l 0.003 0.002 ,. _‘ g 0.001 Tam-m . ___T " li‘llTTlliilll-TTTlllillll 0 60 120 180 240 300 360 420 Tlmber volume (m3/ha) + Selective logging Probability Figure 4.8. Probability of selective logging with respect to timber volume Vegetation types The vegetation dummy variables for dense, open, and transitional forests were all statistically significant. Transitional forest, with 0.9% of likelihood of selective logging was the most selective logging-prone forest type when all other factors are held constant at mean value. Dense and open forests showed 0.7% and 0.6% of likelihood of selective logging, respectively. Deciduous and semi- deciduous forests were not statistically different from the omitted forest type (pioneer vegetation). Although transitional forest is not the largest forest type and does not have the highest timber volume per hectare, it showed to be the most attractive ecotype to loggers. As previously presented, transitional forest also have been object of more forest fires than any other forest types. The predicted effect of forest types, states, protected areas, and temporal variables in the probability of selective logging is presented in Figure 4.9. 143 0.020 0.018 0.016 0.014 0.012 0.010 0.008 0.006 0.004 0.002 Probability El Para uTmnhao Tocantins , fl Mato Grosso u Rondonia I Dense forest I Open forest I Semi-deciduous I Deciduous [j Transitional Outside of protected areas I Inside of protected areas ‘l-Year1999 lYear1996 ‘ —4 Tl Figure 4.9. Probability of selective log’Wpemegetation types, protected areas, and year of analysis The probability of selective logging was three-fold greater outside than inside of protected areas with 0.6% and 0.2% of likelihood of selective logging, respectively. This result shows that protected areas have been reasonably effective in impeding or even slowing the pace of selective logging in the Brazilian Amazon The state dummy variables for Rondénia and Tocantins were not statistically different from the omitted state (Acre) in terms of selective logging probability. The dummy variables for the states of Para, Maranhao, and Mato Grosso were statistically significant. Natural forests located within the state of Maranhao have 1.8% greater chances of selective logging than the omitted state (Acre), immediately followed by forests located in Mato Grosso and Para, both 144 with 1.3% likelihood of selective logging and by holding all other factors constant at the mean value. Similar of what was observed for forest fires, the differences in state environmental policies and legislation may be affecting the likelihood of selective logging within each state. And, finally, the multi-temporal dummy variables also proved to be statistically significant. The year 1999 and 1996 had 0.9% and 0.5% greater chance of selective logging than the omitted year (1992). These results and the results presented in chapter 2 and 3 show that selective logging activities are increasing in area, intensity, and over time in Brazilian Amazon. (Matricardi et al., 2007) speculated that major factors contributing to the increase of selective logging during the period of analysis were the changes in the Brazil’s environmental law, the scarcity of raw material for timber industries, and the occurrence of extreme climatic events. Indeed, (Uhl et al., 1997) had observed that loggers were going farther searching for new timber sources (undisturbed forests) as well as revisiting previously logged forests for species that recently became marketable. 4.5. Conclusions The results derived from the two probit models could explain important spatiotemporal dynamics of selective logging activities and forest fires in the Brazilian Amazon. Based on these results, the occurrence of forest fires were highly correlated with distance to deforestation. This result is supported by Uhl and Buschbacher (1985) who observed that agricultural lands are important ignition sources for forest fires in the Brazilian Amazon. The likelihood of forest 145 fire events is even greater if additional anthropogenic and environmental factors that may increase forest flammability are considered. For example, selectively logged forests were more susceptible to fire than undisturbed forests. This fire susceptibility due to selective logging, however, tends to decrease as forests recover from logging impacts and, four years following selective logging activities, forest moisture can be similar to undisturbed forest (Holdsworth and Uhl, 1997). It is very important to point out that although selective logging seemed to be a factor fueling the increase of forest fires in the study region during the period of analysis, a large amount of selective logging activities and forest fires were spatially distinct events. While distance to deforestation is highly related to forest fires, this factor was not statistically significant in selective logging probability. For instance, the reality of timber scarcity in the old frontier has forced loggers to move ahead of deforestation frontier searching for new timber sources in undisturbed forests (Schmink and Wood, 1992, Pinedo- Vasquez et al., 2001). .Prolonged water deficit also showed to be an important factor that might increase likelihood of forest fires. This result is also corroborated by different authors (Uhl and Buschbacher, 1985, Nepstad et al., 1999, Houghton et al., 2000, Nelson, 2001) who have observed that extreme droughts can increase likelihood of forest fires in tropical regions. Complementarily, (Nelson, 2001) reported that even undisturbed forests became flammable in the Brazilian Amazon upon a severe drought as the one related to the El Nifio event of 1997/98. Similarly, forest fragmentation significantly contributed to increase the 146 chances of forest fires. Indeed, deforestation activities are responsible for creating non-continuous and small forest patches and for increasing forest edges with agricultural lands (Skole and Tucker, 1993, Cochrane et al., 2004, Skole et al., 2004) that results in greater forest flammability (Uhl and Kauffman, 1990, Cochrane, 2001, Cochrane et al., 2004). This anthropogenic phenomenon was studied by (Cochrane, 2001), who concluded that forest fires were strongly correlated with fragmented forest edges in a study site located in the state of Para, Brazil. In additional to the previously discussed factors, I also observed that probability of forest fires and selective logging varied according to forest types. It is presumable that potential differences in soil and forest moisture present in these ecosystems may affect forest fire susceptibility. In this analysis, open, semi-deciduous, and transitional forests were more likely to get on fire than dense and deciduous forests. This effect of vegetation type on forest fire probability is supported by (Nelson, 2001) who observed that secondary and igapo forests were more vulnerable to fire than any other vegetation types during the El Nif‘lo event of 1997-98 in the state of Roraima. Similarly, selective logging activities mostly occurred in transitional, dense, and open forests, which are the predominant vegetation types in the Brazilian Amazon. Transitional forests, however, showed slightly higher probability of selective logging than dense and open forests. In this case, I hypothesized that economic factors (e.g. lower harvesting cost and higher productivity) are driving loggers towards this particular forest type. 147 Forest fire and selective logging likelihood also varied according to the land ownership status. The legal status of protected areas seemed sufficient to, at least, decrease the likelihood of the occurrence of fire and selective logging within their territorial boundaries. However, given the observed increase of selective logging and forest fire between 1992 and 1999, it seems reasonable to expect that human pressure will increase in the future over the natural resources existent within the protected lands established in the Brazilian Amazon. Pedlowski et al. (2005) have already detected the occupation of areas and exploitation of natural resources within the borders of protected lands in the state of Rondénia. Meanwhile, the greatest chances of forest fire and selective logging were found in the states of Para, Mato Grosso, and Maranhao. These states fall within the infamously famous “arc of deforestation” defined by IBAMA (2007). Additionally, the states of Mato Grosso and Para were reported as responsible by most of selective logging detected using remotely sensed data in 1992, 1996, and 1999 in the Brazilian Amazon (Matricardi et al., 2007). Eventual differences in state environmental legislation and law enforcement capabilities may be a factor that promotes or hamper the occurrence of selective logging activities and mmflfims In terms of temporal changes, the results showed that selective logging and forest fires significantly increased between 1992 and 1999. (Matricardi et al., 2007) mentioned that scarcity of timber resources, changes in environmental law, and extreme climatic events are perhaps the most important factors that 148 contribute to increase selective logging in the period of analysis. I would hypothesize that the process of increasing socioeconomic pressure over undisturbed forests will continue, unless intensive environmental monitoring and law enforcement combined with governmental incentives for alternative uses of land forest resources are implemented in Brazilian Amazon. I also hypothesize that at least half of forest fires detected in 1992 and 1996 were ‘intentional’ rather than ‘accidental’ fires, which indicates that landowners intended to burn those forests in order to achieve rapid conversion to agricultural lands. This inference is supported by the results shown in Chapter 3 that indicated that more than 50% of burned forests detected in 1992 and 1996 had been deforested by 1999. This factor, however, was not included in the presented probabilistic models. Finally, it is my hope that the bulk of the results of this research can be used in one hand the expand the modeling of land cover change in the Brazilian Amazon, and on the other hand, also be used to improve governmental programs aimed at enhancing the control of forest fires and the environmental monitoring in the Brazilian Amazon region. 149 CHAPTER V Concluding Remarks 5.1. Seating the current study in the context of global change research In 2000, the area of the Earth covered with forests was estimated as being around 39 million square kilometers. Most of those forest areas were located in tropical areas (47%) and boreal zones (33%). The rest of the forested areas (18%) were located in temperate and subtropics regions. Most of the forests (95%) were then classified as natural forests and a smaller fraction (5%) as forest plantations (VVRI, 2000). Meanwhile, tropical forests are estimated to store 460 to 575 billion metric tons of carbon, an average of 180 metric tons of carbon per acre (NASA, 1998). Therefore, the highest carbon and biodiversity losses occur when a high biomass forest area is converted into low biomass systems such as pasture or agriculture; releasing carbon and other trace gases to the atmosphere while natural habitats are gravely disturbed. The release of trace gases into the atmosphere enhances the Greenhouse effect which contributes to higher temperatures and, consequently, to dramatic global climatic changes (Skole and Tucker, 1993, NASA, 1998, Skole et al., 2004). Deforestation (i.e. conversion of natural forests to non-forest land covers) is annually destroying a significant portion of the world forests. The gross and net rates of global forest loss averaged 17 and 13 million hectares annually, in the 19808. Moreover, the gross and net rates of global deforestation grew to an average of 14.6 and 9.4 million hectares annually in the 1990s. The 19903 rates of annual forest loss correspond to 0.4% globally and 0.8% in the tropics. 150 Consequently, the highest deforestation rates have been observed in developing countries in the tropics (F RA, 2005). Deforestation in the tropics is a critical factor that has several implications for biological diversity, local habitats, and carbon cycle at global scale (Skole and Tucker, 1993, Skole et al., 2004). Approximately 15.4 and 16 million hectares of forest loss was annually observed in tropical countries during 1980-90 and 1990- 00 periods, respectively (Matthews, 2001). More specifically, multi-temporal measurements of deforestation in the Brazilian Amazon provided by (INPE, 2007) demonstrate that more than 2 million hectares of natural forests were slashed annually from 1978 to 2005 in the region. In addition to deforestation, several other processes of land use and land cover change may increase forest degradation in tropical regions such as forest disturbances by selective logging, forest fires, and forest fragmentation (Skole et al., 2004). Skole and Tucker (1993) estimated that areas of disturbed forests due to forest patch isolation and its edge effects in the 19803 were 150% larger than deforested area itself in the Brazilian Amazon. Because of fragmentation, forests will become more susceptible to fire due to an increase of forest disturbances associated to edge effects including the exposure to fires (Cochrane et al., 2004). Based on sawmill survey in the Brazilian Amazon, Nepstad et al.(1999) estimated that the current carbon flux estimates for the Amazon region may be underestimated because of logging areas that have not been accounted for. Nevertheless, in spite of the important contribution of these land use processes to global climate change, only a few attempts have been made to 151 detect and measure forest disturbances, and its extent and impacts using remotely sensed data gathered for tropical regions. As a result, the total area of forest damaged by human activities may have been underestimated. Therefore, relevant questions have yet to be addressed before a better understand of selective logging and forest fire dynamics, their impacts on tropical forests, and their interactions with other land use types is achieved. In this research, based on data obtained remotely and in field studies, I presented new estimates of the extent of selectively logged and burned forests for the Brazilian Amazon basin for 1992, 1996, and 1999. I also estimated the impacts caused by selective logging and forest fire in the region. The results show that the total combined areas of selectively logged and burned forest increased from approximately 11800 km2 to 35600 km2 from 1992 to1999. Selective logging alone was responsible for 60.4% of forest disturbances in the studied period. My estimates indicate that the total active areas of selective logging and forest fire in the Brazilian Amazon have substantially increased from 5468 km2 to 7620 km2 and from 7620 km2 to 17439 km2 in 1992-1996 and 1996- 1999 periods , respectively. These amount of disturbed forests by selective logging and forest fires represent additional land use types that have yet to be properly accounted for. Skole et al. (2004) affirmed that these processes of forest degradation can substantially degrade tropical forests and increase loss of biomass. F urtherrnore, the impact of selective logging on undisturbed forests tropical forests creates a net carbon flux equal to approximately 4-7% of the annual carbon release 152 generated by deforestation (Fearnside, 1997), which can be severely aggravated by forest fires (Uhl and Kauffman, 1990). The intensity of forest disturbances is also increasing in the Brazilian Amazon. As previously mentioned, selective logging was responsible for the largest extent of forest disturbance Amazon-wide. Forest fires, however, were responsible for the greatest impact on canopy cover, causing an average of 18.8% of canopy loss and even greater average of 27.5% of canopy loss if forest fire and selective logging results were combined. This result is supported by (Uhl and Kauffman, 1990) who observed that forest fires in tropical forest can be devastating because of their natural low resistance to fire. Meanwhile, selective logging was responsible for around of ~2% of forest canopy losses. These results indicate that although selective logging may destroy 40-50% of canopy cover in particular study sites (Uhl and Vieira, 1989, Verissimo et al., 1992), it has lower impacts on forest canopy cover at the regional scale. Finally, the results of this analysis must be considered conservative, since under different circumstances, the most cryptic forest degradation by selective logging and forest fires cannot be properly detected. Indeed, Matricardi et al. (2005) and Matricardi et al. (2007) observed that very low intensity selective logging cannot be easily detected using remote sensing approaches. This type of forest disturbance, however, does not cause substantial environmental impacts on natural forests and on fluxes of carbon dioxide. 153 5.2. Research questions revisited o Is selective logging and forest fire causing more forest degradation than othem/ise would occur? According to INPE (2007) estimates, a total area of 440186 kmz, 517065 kmz, and 569269 km2 of tropical forests in the Brazilian Amazon had been deforested by 1992, 1996, and 1999 respectively. Those estimates from INPE also indicate an average increase of deforestation of 18331 km2 year“1 between 1992 and 1999. The results of the present research indicate that the total area affected by selective logging and forest fire correspond to 2.7%, 3.2%, and 6.3% of total deforestation by 1992, 1996, and 1999, respectively. In addition, results showed that active selective logging and forest fire represented an additional of 27.4%, 38.1%, and 87.3% to the outright increase of deforestation in 1992, 1996, and 1999, respectively. Therefore, selective logging activities and forest fires are substantially affecting large extents of forested areas in the Brazilian Amazon. Further results from the case study in Mato Grosso indicate that this trend in forest degradation by selective logging and forest fires may persist, while natural , resources are abundant and accessible in a given area. However, forest fires appeared to be the most aggressive type of forest disturbance, causing an average decrease of 18.8% in forest canopy cover. When forest fires and selective logging were combined, the effect is even greater, leading to an average decrease of 27.5% in forest canopy cover, whereas selective logging alone contributed to a decrease of 2% of forest canopies in the study region. 154 Despite the fact that selective logging only contributed to a decrease of 2%, this process impacted the largest extent of natural forests in the Brazilian Amazon during the period of study. Nevertheless, this study demonstrated that the area covered with natural forests under the impacts of fires and selective logging is rapidly increasing, making these land uses of greater concern. Finally, forests impacted by fires and selective logging showed the ability to rapidly recover from these disturbances if left to fallow, for periods ranging from 5 to 10 years. Therefore, forest regeneration is another very important phenomenon that must be further investigated because it may indicate forest uses and management alternatives aimed at mitigating impacts brought about by anthropogenic activities in tropical regions. o Can we accurately measure these anthropogenic activities in the Brazilian Amazon basin? The automated remote sensing technique based on Spectral Mixture Analysis was an efficient methodological approach for estimating the area affected by forest fire in the Amazon region. This approach was previously employed by Cochrane and Sousa Jr (1998) and Souza et al. (2003) to detect selectively logged and burned forests using Spot imagery in a case study in Para. I further improved, tested, and validated this remote sensing technique for a 30000 km2 study site in the state of Mato Grosso. The accuracy assessment results of this forest fire detection approach indicated 96.0% and 0.91 of overall accuracy and overall kappa statistic, respectively. This technique showed high 155 sensitivity to changes in Non-Photosynthetic Vegetation (NPV) within tropical forests. NPV grows substantially when forests are affected by fires, and its effects are prolonged throughout contiguous forested areas. Indeed, (Nelson, 2001) reported that even ground fires could be detected using Landsat TM imagery. Therefore, based on my remote sensing analyzes and findings of the field studies, I believe that the most fire-impacted forests were accurately detected and mapped. The semi-automated texture analysis and visual interpretation combined also showed to be an efficient remote sensing approach to detect and estimate areas affected by selective logging. The results of the research conducted by Matricardi et al. (2007) showed that most of selectively logged forests were detected and mapped using semi-automated and visual interpretation approaches. These remote sensing approaches showed 92.9% and 0.82 of overall accuracy and overall kappa statistic, respectively. However, I must advise that the results of these methods must be considered as conservative, since, in different circumstances, some cases of selectively logged and burned forests could not be detected. | hypothesize that very low intensity ground fires that did not affect canopy cover were difficult to detect using remote sensing approaches. Similarly, selective logging activities may not be easily detectable using Landsat imagery because of lack of soil exposure by logging features (patios, access roads, etc.) on the ground. 156 o Where are the most severe selective logging and forest fire occurring in that region? Why selective logging and forest fire are occurring there and not somewhere else? Based on the findings of the basin-wide results, most of the impacted forests by selective logging and fires were detected in Mato Grosso, Para, and Maranhao, which are geographically located within the so-called “Arc of Deforestation” defined by the Brazilian Institute of Environment and Renewable Natural Resources as a distinguished zone highly affected by anthropogenic activities in the Brazilian Amazon. While spatial distribution of forest fires were highly correlated with proximity to deforestation areas, selective logging activities were more related to proximity to logging centers and road networks. These findings are supported by Uhl and Buschbacher (1985), Uhl and Kauffman (1990), and Cochrane (2001), who observed that fires from fire-maintained agricultural lands are the main ignition sources for forest fires in the Brazilian Amazon. Additional factors such as prolonged water deficit, selective logging, and forest fragmentation also contributed to increase forest fires, though a combination of all these factors seemed to be a more probable reason for forest fire events occurring in the region. Meanwhile, I also observed that the spatial distribution of selective logging activities is strongly influenced by the distance to logging centers and road networks, which may be associated to transportation costs. As a consequence, loggers have to improve their transportation efficiency continuously to better exploit timber sources in new frontiers of undisturbed forests as the forests next to logging centers become overexploited. During the 157 field work in Mato Grosso I could observe that loggers are commonly using heavy-load (30 to 40 tons) trailer trucks to transport logs from forest sites to sawmill. Finally, the status of land ownership seemed to play an important role in the spatial distribution of both selectively logged and burned forests. For example, only 3.7% of the total impacted forests by selective logging and fires were geographically located within protected areas in the period of analysis. There is growing evidence, however, of an increasing trend for the occurrence of anthropogenic activities within the limits of protected areas. o Is there any spatial pattern of these activities in that region? Are those spatial patterns changing over time? The results of this research show that forest fires and selective logging activities were occurring throughout the Brazilian Amazon at an increasing intensity during the period of 1992 to 1999 (see appendices 0.12 to 0.17). Forest fire events that could rarely be observed in Rondonia and Acre in 1992 were evident in 1996 and 1999 in both states. The most meaningful forest fire and logging clusters were located in the Eastern and Southern Para, Western Maranhao, and Northeastern and Mid-Northern Mato Grosso in 1992, 1996, and 1999. The analysis for 1999 logging and fire mosaics (appendices C.12 to 0.17) revealed the surfacing of new logging centers and fire events in Northwestern and Southwestern Para, and Northwestern Mato Grosso. These mosaics also show that selective logging activities and forest fires have encroached on protected areas in the study region. This spatial feature is especially clear in the Northeastern Mato Grosso. 158 o Is there any interaction between selective logging and other land use or land cover type that may be synergistically causing even more forest disturbances? As previously presented in Chapter 4, selective logging activities significantly increased forest fire likelihood in the Brazilian Amazon. This fact is supported by Uhl and Buschbacher (1985), Uhl and Kauffman (1990), and Cochrane (2001), who observed that selective logging increases forest fire susceptibility in tropical regions. The proximity to agricultural land, however, was the factor that most substantively and significantly affected probability of forest fires in the study region. On the other hand, this factor did not significantly affect selective logging likelihood in the study region. Further juxtaposition between selective logging and forest fire maps indicate less than 7% of overlap between these types of forest disturbances in the period of analysis. These facts indicate that, at the regional scale, most of selective logging and forest fire were spatially distinct events. The results from the basin-wide analysis of forest fires also indicate that only around of 457 km2 could be considered recurrent fires detected over the study period. Moreover, field measurements showed that fuel load averages for study sites in Acre, Rondonia, and Mato Grosso were not significantly different for various forest uses (i.e. logged, burned, and undisturbed forests). Altogether, these facts indicate that the positive association between selective logging and forest fires at the local scale observed by many authors (Holdsworth and Uhl et al. 1997, Cochrane 1999, and Cochrane and Schulze 1999) may not be 159 supported by a basin-wide analysis, since most of the selective logging and forest fires detected did not occur at the same place and time. The results and field measurements also indicated that some forested areas are naturally more fire prone than others, whether logged or not, which indicates that forest fire events at a particular site require very unique local conditions. These may include, but are not limited to, water deficit, forest type, forest disturbance, and the presence of ignition sources. 5.3. Hypotheses revisited Hypothesis 1: Forest impactiby selective Ioggjmctivities increase over ting Ml severely disturb nettle] forests in the B__razilian Amam This hypothesis may be considered true since my results showed that areas of selectively logged forests detected using remotely sensed data increased 500% between 1992 and 1999. These results also showed that selective logging alone contribute to degrade around of 2% of forest canopy compared with undisturbed forests. Selective logging and forest fire combined substantively increases canopy degradation up to 27.5%. Moreover, selective logging is increasing in area and intensity throughout the Brazilian Amazon. It is also important to point out that forest canopy regeneration was very strong (~6% greater than undisturbed forests) in previously logged forest detected in the period of analysis. At the local scale, field measurements indicated that newly selectively logged forests may significantly decrease around 6.7% of canopy cover. lf selective logging and fire combined, canopy cover is decreased by 7.7%. Finally, diversity 160 index, tree mortality and fuel load rates for logged sites were not significantly different from undisturbed forests. Hypothesis 2: Forest fires mostly occur on fire-prone selectively logged forests _a_nd_further increase forest degidation in the §r_azilian Amazon. This hypothesis cannot be accepted as it is stated. My results showed that selective logging significantly increase forest fire probability. However, the juxtaposition of forest fire and selective logging maps showed only approximately 7% of common area between logging and fire. Additional statistical analysis indicated that proximity to deforestation was a factor that substantively and significantly affected forest fire likelihood. Therefore, fire-prone selectively logged forests may increase forest fire probability, but it did not seem to be the major factor that increases forest fire events at the regional scale. The second half of this hypothesis can be accepted as stated. Indeed, the results showed that, when taken as a singular phenomenon, forest fires severely degraded canopy cover (up to ~19%) in the study region. At the local scale, field measurements also indicated that newly burned forests significantly decreased around 12% of canopy cover when compared to undisturbed forests. Tree mortality rate was also significantly higher and diversity index was significantly lower compared to undisturbed and selectively logged forests. Hypothesis 3: yflables that reflect landscape and land use clfirgcten'stics (e. g, vegetation Me, soil, precipitation, deforestation, forest fragmentation. proximity 161 to road network, etc.) explain spatialeistripution and Mability of selective logging and forest fire to occur in the Lrazilian Amazon. This hypothesis can be accepted. In this analysis, variables derived from remotely sensed data representing landscape and land use characteristics were used as input for forest fires and selective logging probit models. These multivariate models permitted to select statistically significant variables that represented factors influencing selective logging and forest fire occurrences in the study area. The final statistical models supported inferences of both the selective logging and forest fire probabilities throughout the study region. The effect of each variable on forest fire and selective logging probabilities was previously presented and discussed. 5.4. Opportunities for further studies lVly study showed a 10 year trend of forest fire and selective logging in the Amazon, but the long-term impacts of these activities are still unknown. I also estimated the extent and impact of selective logging and forest fires on pristine forests in the Brazilian Amazon. In fact, synergistic interactions between these two land use types are poorly understood at regional scales. Therefore, new approaches using finer temporal, spatial, and spectral resolutions satellite imagery should be developed to improve the combined assessment of forest fires and selective logging in tropical regions. Field studies also should be conducted in different sub-regions in the Brazilian Amazon to better understand the process of forest degradation and its synergisms in the Brazilian Amazon. Finally, the development of simulations and scenarios of forest fires and selective logging 162 could be useful to support public policies to achieve a sustainable development in the Amazon region. 163 APPENDICES 164 Appendix A.1. Total deforestation in the Brazilian Amazon from 1978 to 2004 165 800,000 700,000 600,000 , 500,000 - 400,000 300,000 200,000 , 100,000 " Area (km2) 1978 1988 1998 2001 2002 2003 2004 2005 Year I: Cumulative deforestation Source: INPE (2007) Appendix A.1 166 Appendix 3.1. Study site location (Landsat path 226 row 068) in the Amazon State of Mato Grosso, Brazil. 167 —..m XECOQQ< “N“ e 8e 222:2; 82. com E cow 9.82.6.2 8v com o I .- V §l\r//\ \QIJ rrrrrrr \ I .\ T \\ ll lT. I.-- l :o~aE< .33 9:35 B \ .., irrr \l.. T. - T. W .\ \ .5 \. A 32.5w .\ T T, T N 8° . T Boa Ff .T. J \ mum T ..IJrK/ .3 .T ..l|tll1lll|l| / . ......................... 2. ........... zonaE< :53 2: 2556 :55 I ..=N__m:::m 295 6:. .860: L063 Lo NEv. m. cm >_o~mE_xoLaa< .uoLEQm mm; @5085 :5: 3:20 o>=m_:E:o 05 To eEv. «3 Lo xmmE < .902 Low: :o>_m 55 L8 :ozmummLoLo: o>=m_:E:o Lo _Soh,L Loo: :62: 65 L8 3898:: cc: Lang m:o_>oLa :_ 99096: 528 8:5: Lo .02. e .me; :62: ES :_ 8826: $90: 8:5: Lo _EokeL Low: :95 65 L2 3898:: En Loo: w:o_>oL: :_ c.2090: 393 8:5: :8 830. .6 .30.: o Lao.» 52¢ 65 :_ 62096: :88: 8.5:: ::m comma. :0 _the Loo: :96 65 L8 88900:: :5 Low: 9039: :_ 8896: 6.28 830. Lo .90... 6 :8: $36 65 :_ 3826: 7.92 :33. Lo .90... .umoLoL 39:86:: o>=m_:E:o .30.: o 186 momma 0mm: 03 Qmm : Nmom fimmog Lu Rad :Vmww woom 0. e39 348 Doom mwmoé when: v.89: mmmmm 4.80.9 meow D: E @va vmmm 0mm: 30me Hm teem tweed Named? meow 0.336 v.8: mdmm mam: Memo; 0. e :3 Odom: 5mm e. 3 room NEW: Qmmm mwmw N ewe Comm; 03“: N Ema 0m 5.? ooow .4. EN: WEN Owov 0mm v.8: 0:3: :8: ode El 39 4.936 33m ow? 0mm 0N9 Noam o.wmw.m @309 mm? mowed wam :98 mm: N8 0305 Named @085. .83 @086 0.8m who who How Qwood momma 343.2 89 Q89: 3w em «.03 ad: Own: mowed comm; 33.8 mm? seem: comm mdm 0mm 2.: Wmooé 36.3.? No.3. 5 ”some @086 w. Sum mmwe mm? 0.34 ohm: mwewé 33.3 mm? chow: Nmmm - rm: - mow: mammvm no? 89:98:: 506960 03898:: 3:28:80 08633:: 3:28qu Tees: Tees: Tog: 8:5: ES: Tare: ,_ 8.58580 2:0 $98 855 .w 830. 262698 2:0 832 262898 . Emma“. Lmo> 0:33:50 39:56:: 398 89320 Appendix 8.10. Forest canopy losses estimated using multi-regression model for the study area 187 Forest canopy losses estimated using multi-regression model for the study area N = 49583 observations (3000m x 3000m systematic sampling grid) R2 = 0.6307; Adj. R2 = 0.6305; Prob > F = 0.000; F(23, 49559) = 3526.17 Constant and Coefficient Std. Error t P (2- [95% Conf. Interval] Variables tails) Constant -235.0 12.96792 -18. 12 0.000 -260.46 -209.626 Deforestation -53.9 0.2091 1 -257.7 0.000 -54.294 -53.474 Newly logged -5.0 0.40512 -12.34 0.000 -5.7937 -4.2057 Old logged forest detectable(*) -1 .6 0.3423 -4.62 0.000 -2.2521 -0.9103 Old logged forest non-detectable(“) 3.1 0.2428 12.58 0.000 2.57897 3.53075 Newly logged & burned forest -35.6 1.05498 -33.78 0.000 -37.709 -33.573 Newly burned ' -28.9 0.99566 -29.05 0.000 -30.877 -26.974 Old burned forest detectable (*) -12.6 0.76258 -16.49 0.000 -14.072 -11.082 Old burned forest non-detectable(**) -1 .0 0.71549 -1 .45 0.147 -2.4412 0.36352 Old logged & burned forest detectable(*) -25.6 1 .03242 -24.75 0.000 -27.58 -23.533 Old logged & burned forest non- detectab|e(**) -4.7 0.54397 -8.57 0.000 -5.7269 -3.5945 Water body -61.3 1.81431 -33.8 0.000 -64.871 -57.759 Year of 1993 -8.8 0.36602 -24.05 0.000 -9.5186 -8.0838 Year of 1994 -4.5 0.36661 -12.23 0.000 -5.2039 -3.7668 Year of 1995 -1.2 0.3669 -3.33 0.001 -1.9414 -0.5031 Year of 1996 -3.1 0.36738 -8.45 0.000 -3.8251 -2.385 Year of 1997 -5.6 0.36799 -15.11 0.000 -6.2802 -4.8377 Year of 1998 -3.5 0.36895 -9.41 0.000 -4.1957 -2.7494 Year of 1999 84 0.36992 -22.61 0.000 -9.0905 -7.6404 Year of 2000 -4.4 0.37366 -11.83 0.000 -5. 1537 -3.6889 Year of 2001 -7.1 0.37501 -18.91 0.000 -7.8252 -6.3551 Year of 2002 -6.5 0.37629 -17.31 0.000 -7.2502 -5.7751 Year of 2003 -5.0 0.37739 -13.23 0.000 -5.7316 -4.2522 Year of 2004 0.1 0.37891 0.25 0.806 -0.6497 0.83561 X coordinate (km) -0.001 0.0015 -0.43 0.669 -0.0036 0.0023 Y coordinate (km) 0.037 0.001497 24.7 0.000 0.03403 0.0399 * The term detectable refers to previously logged and/or burned forests that persist detectable on satellite imagery. ** The term non-detectable refers to previously logged and/or burned forests that do not persist detectable on satellite imagery. Note: In this multiple-regression analysis, undisturbed forest and the year of 1992 were used as omitted variables for land use and annual changes, respectively. Appendix 8.10 188 Appendix C.1. Study region location and Landsat scenes used in the spatiotemporal assessment of selective logging and forest fire in the Legal Amazon 189 to 5.95:2 “Hun EM :3 2:. a 2:. one I. >2... 3% . 32 :5 .39 .33 . 3:1 .553:an 3:3: nan—Esau DNN QNNBN NnN N8 An—Haa L \ 33%: «F: - a E 20N35 190 Appendix C.2. Acquisition dates of the Landsat imagery for 1992, 1996, and 1999 191 Acquisition dates of the Landsat imagery for 1992, 1996, and 1999 Path/Row Acquisition Date 1992 1996 1999 221/063 July 11, 1992 May 30, 1997 May 14, 2000 222/062 July 24, 1991 July 5, 1996 July 14, 1999 222/063 July 24, 1991 June 3, 1996 August 23, 1999 222/064(1) August 25, 1991 June 19, 1996 August 23, 1999 223/062 August 16, 1991 May 28, 1997 July 13, 1999 223/063 May 28, 1991 July 12, 1996 July 13, 1999 223/064 August 10, 1992 June 10, 1996 July 13, 1999 223/065 June 02, 1993 June 10, 1996 July 13, 1999 223/066 July 25, 1992 June 10, 1996 July 13, 1999 223/0670) - - August 30, 1999 224/062(2) - - October 24, 1999 224/063 June 22, 1992 July 19, 1996 October 8, 1999 224/064(2) - - October 8, 1999 224/065 July 16, 1992 June 19, 1996 October 8, 1999 224/066 July 16, 1992 July 3, 1996 October 8,1999 224/067 July 16, 1992 July 3, 1996 October 8,1999 224/O68 July 23, 1992 July 3, 1996 August 21, 1999 224/069 July 23, 1992 July 3, 1996 August 21, 1999 225/0670) July 23, 1992 June 8, 1996 August 12, 1999 225/0680) July 23, 1992 August 11, 1996 August 12, 1999 225/069 June 21, 1992 August 11, 1996 August 12, 1999 225/0700) - - August 12, 1999 226/063 July 20, 1991 June 18, 1997 August 3, 1999 226/066(2) - - August 3, 1999 226/067 May 19, 1992 July 1, 1996 August 19, 1999 226/068 May 19, 1992 July 1, 1996 August 19, 1999 226/069 May 19, 1992 July 1, 1996 August 19, 1999 226/070(2) - - August 3, 1999 227/0620’) - - August 10, 1999 227/0650) August 06, 1992 August 09, 1996 August 10, 1999 227/067 August 6, 1992 July 24, 1996 August 10, 1999 227/068 August6,1992 June 6, 1996 August 10, 1999 227/069 July 5, 1992 June 6, 1996 August 10, 1999 227/070 July 5, 1992 June 6, 1996 August 10, 1999 228/067(2) - - August 17, 1999 228/068 June 18, 1992 June 13, 1996 August 17, 1999 228/069 June 18, 1992 June 13, 1996 August 17, 1999 229/067 my 3, 1992 July 22, 1996 August 8, 1999 1 Selectively logged forest not mapped in 1992 and 1996. 2 Selectively logged and burned forest not mapped in 1992 and 1996. Appendix C.2. To be continued 192 Acquisition dates of the Landsat imagery for 1992, 1996, and 1999 Path/Row Acquisition Date 1992 1996 1999 229/068 July 11, 1992 July 22, 1996 October 11, 1999 229/069 June 25, 1992 July 6, 1996 August 8, 1999 229/070 July 11, 1992 June 23, 1997 August 8, 1999 230/068 July 10, 1992 October 17, 1996 August 15, 1999 230/069 May 15, 1992 October 17, 1996 July 30, 1999 232/067 June 22, 1992 June 25, 1996 June 28, 2000 002/067 August 30, 1992 August 1, 1996 Appendix C.2. Continued. 193 August 2, 1999 Appendix C.3. Case study (fieldwork) locations in the Brazilian Amazon 194 no 565:? Ex coo oov com o moez hoe: 00:51. nee: eoez' o NOPE 5:86.36 e 533233335 0 Dzwow4 6T. :25 :o 35 03.52 \ \Wtf Ex 000.. 23:30... .\ H : ..\ \ 2am x, \t t / 3:552 /, .L ,_, \x.) :auE LL \p 2583: ZON<_2< gem... o.r=N<¢m com 0 2:22.31 ”NCONNE t2}. ooow com o Sow: .82 our. El 855 21 room oEHHMW. co< :0 >20 :o~mE< :mENSm 05 :_ 30380. 0.83205 >25 3:0 195 Appendix 0.4. Case study and transect locations and characteristics 196 to 5.2.8.2 :26 988 8 8:2 858 88.8 8 x 8m M38- 832- oms 88:0 682 8:2 6.6 88 a 8.5.. 858 2.58: S x 8m 83.8.. 88.2- are 886 682 8:2 :8 88 a 8:2 883 S x com 838. 8an w; 885 292 8:2 :8 83 3 8:2 883 S x 8.8 8.8.8- 8.0?- Ee 6880 682 8:2 882 893283 2 x 08 83.8- «8.2- .88 88.6 082 8:2 882 883283 3 x 8.8 838- mmmd- was 885 282 8:2 6.6 88 2 883 S x 8m NE?- 857 E 8 88.6 682 8:2 S_o 88 8 8539883 8 x 8m 8:8- 8:. e T 2 8 88.6 682 85 S_o .883 3 858 88. 88 co 3 x 08 808- mmm. e e- S 3 885 682 6.0 88> i 858 238: 8 x 08 80.8.- 8m. e T : 8 885 682 8:2 :8 88 a 8:2 883 S x 8m 83.8- 80 e T 9 3 885 682 66 88 3 858 3:8: S x 08 88.8- 837 8 e 885 682 5:2 882 88328: S x com. 888- 8:9- 8 e. 98 80m 85: 88328: S x 08 $8.8- 82:- B 8 9888: 80m 6.6 88 a 883 S x 8m «88. 88.8- 8 e 9888. S_o 88 2 883 S x 8.8. N88- 888- 8 8 888$ 80m 6.0 88 a 883 S x 8: :08- @89- 8 we 83 88 : 858.883 8 x 08 98.8- 039- 8 s 83 89a 882 8898 88:0 8 x 08 88.5. 83- 8 8 82 8.82 88328: S x 08 88.5- Ema- 8 s 89a 8% E: :o_m:®E_o $983 $833 0. Q_ mozmtofiogmzo Sew Hoomcwb- 00:56:04 $03:le— uoomcm-c. 39w 31w 197 Appendix 05. Transect design for fieldwork measurements 198 no 5883 €3.23on £00: :2... ucm .Eo On A ucm .Eo 0.5-Om .Eo mN v 80820 00:5 55.3 32:05 u:_:_m:..0.. :0 E300 "0:2 .03“. 300:9: E can 05 320 So or A .30 $2: ”EoEqumoE ran 05 5:85.50. 00....- .:.0 905 m 5230: .8085 0:... E0 m v 3.08.20 ”momma... .2089: EEoEu 02: 55.3 moo: 05 5:80:30: 36 .58 30.6030 :8 0.. A Imo 53> moo: 2:080:8«0E 0mg _0:u_ :88. .828. 52... ll €825: 800:0: .8 .88. so: $58. 88.6 :0 EoEoSmmoE Imo 0:0 €00.05 :0 .850: .950 .0003 520:8 ozm0m4 ooh 60:35.52 00... 600:: :0 30:5: 05 :0 ano 3000:“: £02 mhzgmm—Dm4g Dam—n. a . NO Em . \.\I II E... 8 _ :5 w 5 Eu. ES _ \8 ‘. _ _ _ _ Em_ _Em_Em_ Em._sm \\ \\ =58 wecmEoSmmoE 0:02.20: :0: :9000 88:0:- 199 Appendix C.6. List of tree species identified and recorded during the field work in the States of Acre, Rondbnia, and Mato Grosso. List of tree species identified and recorded during the field work in the States of Acre, Rondonia, and Mato Grosso Species Scientific Name Abacaterana Aniba burchellii Kostern Abiorana Pouten'a macrophylla (Lam.) Eyma Abiu Pouten'a sagotiana (Baill) Eyma Acai Euterpe oleraceae Mart. Acapu Minquartia guianensis Aubl. Algodao Bombax sp Amarelao Qua/ea dinizii Ducke Amendoim-Bravo Pterogyne nitens Tul. AmesclalBreu Trattinickia burseraefolia Mart. Willd. Angelim Hymenolobium sen'ceum Ducke Angelim Pedra Dinizia excelsa Ducke Angico Cassia fastuosa Willd. Apui Ficus tn'gona L.f. Babacu (*) Attalea sp Bacuri Symphonia globulifera L.f. Bagaceira Bagassa guianensis Aubl. Banana-do-mato (*) Musa spp Bandarra (*) Barriguda Bauchorana Bolateira Branquilho Branquinho Breu grande Cafezinho Caja CambaralCedrinho Canafistula Canela Capirana Caraipe Caroba Castanheira Catanudo Catuaba / Breu Leite Caucho Caxeta / Mandioqueira Cedro Champagne/Cumaru Chicha/ Capote Cinzeiro Schizolobium amazonicum (H ubber) Ducke Chon'sia integrifolia Ulbr. Ecclinusa guianensis Eyma Manilkara huben' (Ducke) Chevalier Albizia hasslen'i (Chodat) Burkart Sebastiana sp Protium apiculatum Swartz Caesan'a sp Spondias dulcis F orst. En'sma uncinatum Warm. Cassia Ieiandra Benth. Nectandra cuspidata Nees Calycophyllum spruceanum Benth Licania pruinosa R. Benoist Jacaranda copaia (Aubl.) D. Don Bertholletia excelsa Humb. Bonpl Chrysophyllum sp Th yrsodium schomburgkianum Benth. Castilla uIei Warb. Qua/ea albiflora Warm. Cedrela odorata L. Dipten'x odorata (Aubl.) Willd. Sterculia speciosa K. Sch um Terminalia amazonica QF. Gmell Excell. Appendix C.6. To be continued... 201 List of tree species identified in the field work in the States of Acre, Rondénia, and Mato Grosso Species Scientific Name Cipouba Parkia discolor Spruce ex. Benth. Copaiba Copaifera guianensis Desf. Copiuba Goupia graba Ambl. Cumaru Ferro Dipten‘x trifoliata Ducke Cupuacu Theobroma bicolor Humb & Bonpl. Envireira Rollinia sp Escorrega Macaco Escova de Macaco Espeteiro Farinha Seca Favefia Figueira Freijo Garapa/Garapeira Garrote Goiabinha (*) Guanandi Guaranta Guariuba lmbauba (*) Imburana Inga lpe Mauba Jambo Jatoba (Jatai) Jenipapo Jito Joao Mole Lacre Landim Leiteiro Louro Macaranduba Macuco Mamica de Porca Mamui Mandiocao Marapaju Marmelada Matamata Capirona huben'ana Ducke Apeiba sp Casean'a sylvestris Sw. Polygonanthus amazonicus Ducke Parkia nitida Miq. Ficus malacocarpa Standl. Cordia sagoti L. M. Johnston. Apuleia Ieiocarpa (Vogel) J .F. Macbr. Brosimum utile (H.B.K.) Pittier Bellucia grossulan'oides (L.) Triana Calophyllum brasiliense Cambess. Esenbeckia Ieiocarpa Engl. Clan'sia racemosa Ruiz & Pav. Cecropia uIei Snethl. Amburana acreana (Ducke) A.C. Sm. Inga macrophylla H.B.K. Tabebuia senatifolia (Vahl) Nichols. Mezilaurus itauba (Meissn.) Taubert ex Mez. Eugenia malaccensis L. Hymenea courban'l L. Genipa caruto H.B.K. Quarea silvatica CDC. Neea opositifolia Ruiz & Pav. Vismia guianensis Pers. Calophyllum brasiliense Cambess. Himatanthus sucuuba (Spruce ex. Mull. Arg.) Woodson Ocotea rubra Mez. Manilkara excelsa (Ducke) Standl. Hirtella racemosa Lam. Zanthoxylum rhoidolium Lam Jaracatia spinosa (Aubl.) A. DC. Schefflera morototoni (Aubl.) Decne. & Planch. Manilkara Iongifolia (A.DC.) Dubard Amaioua guianensis Aubl. Eschweileragrandifolia (AublLSandwith Appendix C.6. To be continued... 202 Species Scientific Name Mirindiba Terminalia amazonica (J.F. Gmel) Excell. Monjolo Enterolobium maximum Ducke Mororo Bauhinia macrostachya (Raddi) J.F. Macbr. Muiracatiara Astronium gracile Engler Mulateiro Pentaclethra macro/oba (Willd.) Kuntze Mulungu Malouetia tamaquan'na (Aubl.) A.DC. Murici Byrsonima chrysophylla H.B.K. Naja Maximiliana man'pa (Aubl.) Drude Nao identificada Unknown Orelha de Negro Enterolobium contortisiliquum (Vel|.) Morong Orucuri Siagus sp Paineira Ceiba Pentandra (L) Gaertn. Palheira (*) Geonoma sp Palmeira (*) Livistoma chinensis (Jacq.) R.Br. Palmeira Norjesu (*) Parna Pata de Vaca Pau cebola Clusia rosea Jacq. Pau d'alho Seguien'a Iangsdorffii Mog Paxiuba (*) PALMAE Pente de Macaco Bagassa guianensis Aubl. Pequia Caryocar gracile Wittm. Peroba Mico Aspidospenna pyn'folium Mart. Pindaiba Xylobia frutescens Aubl. Pororoca Curatella americana L. Quina Coutarea hexandra (Jack.) K. Schum. Roxinho Peltogyne paradoxa Ducke Sangue lryanthera elliptica Ducke Seringueira Hevea brasiliensis Mull. Arg Sucupira Bowdichia virgilioides H.B.K. Sumauma Ceiba Pentandra Gaertn. Tachi Tachigalia paniculata Aublet Tamarindo Man‘iodendron elatum (Ducke) Gleason Tauari Couratan' guianensis Aubl. Tucuma Astrocaryum aculeatum G.F. W. Meyer Uchi Endopleura uchi (Huber) Cuatr. Unha de gato (*) Mimosa sp Urtiga (*) Cnidoscolus pubescens (Fax) Fax & k. Hoffm. Velame Sclelorobium paniculata Vogel Violeta Peltogyne paradoxa Ducke Virola Virola sun'namensis (Ro|.) Warb. Livistoma sp Brosimum sp Bauhinia sp * Regeneration (secondary) tree species Appendix C.6. Continued. 203 Appendix C]. Estimates of indicators of forest disturbances by selective logging and forest fires based on field measurements in the States of Acre, Rondonia, and Mato Grosso 204 ...00::_::00 0: 0 ._. ho 50:00}: 0: 00.0 EN: mm mm: 0mm 800:0 0:02 0Q: om 3.0 00.3 00 mm 000 00080 0:02 or: om Rm 00.0: mm 3» 0mm 800:0 0:02 0:: mm mm: 00.0: 0.0 «0 0mm 000:0 0:02 .20.: 3 0.0.0 omen 0: mm 000 800:0 0:02 0:: 0: m: 00.8 00 m: 30 080:0 0:02 mt: 00 00.: omNm 00 mm mm: 00080 0:02 .3 u: om 8.0 00.: om ow 05 800:0 0:02 m: u: m: Bum 00.0: 0: mm 00m 800:0 0:02 m: :: 0m 0: 000: mm mm mom 800:0 0:02 S u: 0: 80 5mm om 00 «mm 00080 802 o: 0 0:. 3.: 00.0: m0 mm 3.0 800:0 0:02 mo :: m0 000 mmem 00 0: 00m 9:00:00. mo 0.: 00 8.0 9.0m mm mm Sm 0_:00:0m B 0: 0:. NWN 00.0w mm: mm NR 0_:00:0m mo 0:: 00 E: omwm 00: ON 0.00 0_:00:0m mo :: 00: mod 3.0m 00m mm 030 0:90. 00 u: m: 00.0 mm: 00: 00 00.0 0:0< mo 0: mm 9.: 00m: 0: 0 0mm 0:04 mo: mm 00.0 3.9: om: 0: 0:0 0:0< :00 0:: 0&9: 00:0 :0::m:: 0:: 0:: 0:: :0:0:0:000m _000: 0000 00:0 _000m 0.00% 0000 20303.3. :0:000_ 05 o_ 2.50 E0 0: A: 000:: 800:0: 205 00:00:00 0.0 50:00:; 0.: 00.0: 0:: 000: 00.0 00.0 :0. 00.00 0.00 00:: 0.0 00.00 00: 00:0 00.0 00.0 0.0 00.00 «.00 0:0 0.0 00.00 00: 0000 00.0 00.0 0.:: 00:: 0.0: 0:: 0:.0 :.:0: 3.0 0000 00.0 00.0 0.0 00.0 0.0: :.:00 0.0: 5.00 000 0000 00.0 00.0 0.0 0:.:: 0.0 0::" 0.0 :.00 000 $0.00 00.0 00.0 0.0 00.0 0.0 0 :0 0.0 0.00 000 00:0 00.0 00.0 0.0: 0.: 0.0 w: u 0.0 0.00 000 0000 00.0 00.0 0.0: 0.00 0.00 0: 0 0.0 :.: :: E: 000: 3.0 :00 0.0 0.0: 0.0: 0: n 0.0 0.00 000 0000 00.0 00.0 0.0 0.0 0.0: :2: 0.0 0.00 000 0000 00.0 :00 0.00 0.0: 0.0 0::" 0.0 0.:0 0:0 0:0: 00.0 00.0 0.00 0.0 0.0: 00:" 0.0 0.00 E 000 00.0: 00.0 0.0: 0.: 0.0 00:w 0.0 0.00 00 000 00.0: 00.0 0.0: 0.0: 0.0 00:: 0.0 000: 00: 000 00.0: 00.0 0.00 :.0: 0.:. 000 :.0 0.00 00 30: 00.0: 00.0 0.00 :.0 0.0 00:: 0.0 0.0: 000 0000 00.0: 00.0 0.00 0.0 0.0 00:: 0.0 :.:0 000 0000 00.0: 00.0 0.00 0.0: :.0: 00:: 0.0 0.00 000 0000 00.00 00.0 0.0 0.0 0.: 0 00: :.0 :00 000 0000 00.0: «0.0 0.0 0.: 0.0 :0:W 0:3 020:9 :00 :00 2:82: 0:084 .080 2.08:: 5000 0:002: ::0 0 :-0 Eu 0 v «:00 : _Qm :0:0:0:000m 30: 0:0: 320:0: :05: 002 _000 :0::0_0:0_>_0:: D_ 000:020 000:0>< 5000:0000. 0005 E0 0: A: 006000 00:: 600:0; 206 Appendix C.8. Empirical linear relationship between various vegetation indices and forest canopy coverage based on field measurements for the study sites in Mato Grosso, Rondonia, and Acre. 207 Mato Grosso site, N= 47 208 Vegetation Index R2 df F(1,45) Sigf. MSAVI 0.840 45 236.83 0.000 GEMI 0.802 45 182.21 0.000 NDVI 0.672 45 92.26 0.000 MSAVIaf 0.810 45 191.9 0.000 GEM|2,1 0.776 45 155.79 0.000 AFRI 0.603 45 68.25 0.000 GV 0.762 45 144.24 0.000 Rondonia study site, N= 32 Vegetation Index R2 df F(1,30) Sigf. MSAVI 0.7374 30 84.26 0.000 GEMI 0.6991 30 69.7 0.000 NDVI 0.6018 30 45.35 0.000 MSAVlaf 0.6983 30 69.44 0.000 GEMI2.1 0.6972 30 69.07 0.000 AFRI 0.5772 30 40.96 0.000 GV 0.6897 30 66.67 0.000 Acre study site, N = 30 Vegtation Index R2 df F(1,28) Sigf. MSAVI 0.8125 28 121.3 0.000 GEMI 0.7304 28 75.85 0.000 NDVI 0.7181 28 71.34 0.000 MSAVIaf 0.8035 28 114.49 0.000 GEM|2.1 0.705 28 66.9 0.000 AFRI 0.7147 28 70.14 0.000 GV 0.7416 28 80.34 0.000 Appendix C.8 Appendix C.9. Basin-wide results of selective logging and burned forest detection for 1992, 1996, and 1999 209 000:0:00 0: o... 0.0 50:000.: 0.000 0. :: 0.00: 0.00 0.0 0.000 0.0: 0. : 00:0 009000 0.00 - 0.0 - - - - - - 6000.000 0.0 - 0.0 0.00 :.0 0.0 0.0 - 0.: 009000 - - - - - - - €080.00 0.00 0.0 0.000 0.0: 0. : 0.000 0.: 0.0 0.000 009000 0.00 0.0 0.00: - - 0.000 - - 0.00: 300900 0.0: - 0.000 - - 0.000 - - :.:00 6009000 - 0.3.. - - 0.000 - - 0.:: €082.00 m: - 0:00.: :.o - 0.000 - - 0.00: 9008500 00 :0 0.0 0. :0: 0.0: 0. : 0.00 :.00 0.0 00:0 0900 0.000 :00 00.00.: 0. :0: 0.00 0.00: 0.000 0.00 0.000 009.00 0.00 :.0: :.0: 0.00 0.0 0. K 0.00 - 0.00 009.000 0.0.0 0.0 0.00 :.0: :.0 0.3. 0.... - ...00 009.000 0. :00 0.0: 0.00: 0. :: 0.0 0.00 - - - 9009000 - 0.0 - - 00 - - - 5:00.000 .10 0.0 :00 0.0 0.0 :.00 0.00 0.: 0. :0 009000 0.00 - 0.00 0.0: 0.0 09.00 0.00 :.: 0. : :: 009000 0.000 0.0 0.00 09.0 0.0 0.00 .000 - 0.0: 009000 0.03.0 0000 0.000 00:0: :.:0: 0.000 0.000 0.00 :.00 009000 :.000.0 0.000 000.0. 0.000.: 0.000 0. : :0 0.000 :00 0.00: 009000 0.:: 0.0 0. :0 0.: :.0 0.00 - 0.0 0.:: 6009000 0. :00.0 0.000 0.00:. 0.000 0.00: 0.00:. 0.0.00 0.00 0.0.0 009000 0. :00 :.000 0.0.00 0.000 0.00 0.3.0 0.000 0.00 :.000 009000 :00 :.0: 0.00 0.: :.0: 0.:: 0.00 0.00 0.000 009:00 0.00 - ...00 0.00 - 0. :: 0.: - :.0 009000 .05.. 0:3 .05.. 6%.. 0:2. 0:2. .05.. We: .05.. 2:0 0.: 00000.. 2:0 2:0 C 00000.. 2:0 2:0 00000.. 2:0 500 00000.. .0 00:50 00:50 00000.. .0 00:50 0055 00000.. .0 00:50. 00:50 .0 000: 000: 000: :.0n. 210 . 0005.50 .06 50:00.2 :.00:.00 0000.0 0000.0 0. :00.0 0.000.: 0.00 :.0 :.000.0 0. :00 0000.0 .0000 0.00: - 0.0 - - 0.0 0.0: - :.0 009000 0.00 0.0 0.00 0.00 0.0 0.0: :.0: 0. : 0.00 009000 0.00: 0.0 0.00: 0. :0 0.0 0.00 0.0: - 0.00 009000 0.00 0. : 0.00 0.00 - 0.0 0.00 0.0 0.00 009000 0.0: 0.0 0.00 0.0 0.0 0.00 0.0 - 0.0 009000 0. : :0 0.00 0.00: 0.00 0.0 0. :: 0.0 :.0 0.00 009000 0.000 0.0 0.0: 0.00 - 0.0: 0.0 - 0.0: 009000 1 0.000 0.0 0.00 0.00 0.0 0. :: 0.0: 0.0 :. :: 009000 «A 0.000 0. :0 0.00: 0.00: 0.00 0.00: 0.00: 0.0 :.00: 009000 :. :: - :.00 :.0: - 0.0 - - - $009000 0.0: :.0 0.00 0.0 - - 0.0 - - 009000 0.000 0. :0 0.00: 0.000 0.0: 0.00 :.000 0.0 0.00 009000 0.00:. : 0. :0: 0.000 0.000 0.00 0.000 0.000 0. 00 0.0 :0 009000 0.00: 0.0 :.00: 0.0: 0.0 0.00: 0.0 0.0 0.000 009000 0.0:: 0. : :.00 - - 0.0 - - 0.0 $009000 0.000 0.0 0.00 0.0: :.0 :.0 - - - 7.009000 0. : - 0. :0 - - - - - - $009000 0000.0 0.000 0.000 :.000.: 0.00 0.0 :0 0.000 0.00 0.00: 009000 0. :00.0 0.000 0.000 0.0:0.: 0.00 0. :0: 0.000.: 0.00 0.000 009000 0:2. 0%.. 05... 0E... 0%.. 050 :5... 0:2. 0:2. 2:0 A... 00000.. 2:0 2:0 C 00000.. 2:0 2:0 00000.. 2:0 .500 00000.. .0 00:50 00:50 00000.. 0 00:50 00:50 00000.. .0 00:50 00:50 .0 000: 000: 000: £00 Appendix C.10. Selectively logged and burned forests detected by State in the Brazilian Amazon 212 2.0 50:32 :.00:_00 0000.0 0000.0 0.:00.0 0.000.: 0.00:.0 :.000.0 0.:00 0000.0 .060 0.0: - 0.00 0.:: 0.0 0.00: 0.0 0.0 :.00 0:0:0000 - - - - - - - - - 08.050 0.000 0.0 0.00: 0.00: 0.: 0.00 0.00 0.0 0.:0 9:00:00 0000.0 0.0:0.: 0000.0 0.00:.0 0.000.: :.000.0 0.00:.0 0.000 0.000.: 0:0n. 0.000.:: 0.000 0.:00.0 00:00 0.000 0000.0 0000.0 :.00: 0.:00.0 00080 0.0.2 0000.0 0.000 0.000 0.000 0.0:: 0.000 0.000 0.00 0.000 005:0:02 - - - - - - - - - 00:80:00 - - - - - - - - - 000:2. 0.00 - 0.00 0.00 - 0.:: 0.0 0.0 0.0 0:00. .05.. 005.. .05.. .05. .05.. .05.. .05.. .05.. .05.. 2:0 F. 00000.. 2:0 2:0 A“. 00000.. 2:0 2:0 00000.. 2:0 0.0.0 00000.. .0 00:50 00:50 00000.. .0 00:50 00:50 00000.. .0 00:50 00:50 000: 000: 000: 213 Appendix C.11. Forest canopy losses estimated using multi-regression model for the study region 214 Variables and Coef. Std. Err. t P (2 tails) [95% Conf. Constant Interval] Constant 95.5 0.2461 387.83 0.000 95.0 95.9 Deforestation -49.0 0.1724 -284.30 0.000 -49.4 -48.7 Secondary Regrowth -6.8 0.2297 -29.74 0.000 -7.3 —6.4 Cerrado (Savannah) -39.2 0.1573 -249.37 0.000 -39.5 -38.9 Water body -66.8 0.5647 -118.36 0.000 -67.9 -65.7 Newly logged (1) -1.6 0.4895 -3.28 0.001 -2.6 -0.6 Newly burned (1) -18.8 0.6250 -30.12 0.000 -20.1 -17.6 Newly logged & burned ( ) -27.5 1.3681 -20.07 0.000 -30.1 —24.8 Previously logged (2) 5.8 1.4327 4.05 0.000 3.0 8.6 Previously burned (2) -2.5 1.1203 -2.25 0.024 -4.7 -O.3 Previously logged & burned (2) -9.7 1.4907 -6.48 0.000 -12.6 -6.7 Year 1996 1.0 0.1381 7.19 0.000 0.7 1.3 Year 1999 -5.1 0.1324 -38.29 0.000 -5.3 -4.8 Longitude (km) —0.008 0.0001 -59.48 0.000 -0.008 -0.007 Latitude (km) 0.012 0.0002 58.34 0.000 0.011 0.012 ‘ The term newly refers to logging and/or burning activities occurred during 1993-96 and 1997-99 intervals, detected by 1996 and 1999, respectively. 2 The term previously refers to logging and/or burning activities detected by 1992 and 1996 that persisted detectable on Landsat imagery by 1996 and 1999, respectively. N = 154635 observations (5000m x 5000m systematic sampling grid) R2 = 0.5285; Adj. R2 = 0.5284; Prob > F = 0.000; F(14, 154620) = 12377.16 Appendix C.11 215 Appendix C.12. Spatial distribution and intensity (logged area I625 km2) of selectively logged forests detected in 1992 216 Spatial distribution and intensity (logged area / 625 km2) of selectively logged forests detected in 1992 701w sogw 1'10 1 , «MLI IU I 1 IV I 0° 0. 10°S -10°S Logged area (1992) ‘ 0% l : l : ‘ = 35% l l = 1 ' = 70% l 20°s ‘ * 20°s l l i 70"W 60°W 50°s Appendix C.12 217 Appendix C.13. Spatial distribution and intensity (logged area I625 km2) of selectively logged forests detected in 1996 218 Spatial distribution and intensity (logged area / 625 km2) of selectively logged forests detected in 1996 70gw 60W 1 10°s- ‘ , -10°s 1 Rondonia” ' 1| I I. ' l flab m Logged arm (1996) l j _ 0% ‘ C l ’ = l “ g 35% . l = \ —=— i : 70% 0 300 600 900 Km 20°s 1 1 20‘s 7o'°w 605w 503w Appendix C.13 219 Appendix C.14. Spatial distribution and intensity (logged area / 625 km2) of selectively logged forests detected in 1999 220 Spatial distribution and intensity (logged area / 625 km2) of selectively logged forests detected in 1999 707w 60’W 10°11 1 10°N N 1 l W>E ] S , Area of Study 0° ' ' ff . ' [I .. r f ...‘1 — L“ Logged area (1999) % w u: a? IIIIIIIIII O N o 33 WMC Lu 0 l 20°s l 1 Appendix C.14 Appendix C.15. Spatial distribution and intensity (burned area / 625 km2) of burned forests detected in 1992 222 Spatial distribution and intensity (burned area / 625 km2) of burned forests detected in 1992 Burned forest area (1 1 I o a? or a! ‘3 as (l) anon £U O Appendix C.15 223 Appendix C.16. Spatial distribution and intensity (burned area I 625 km2) of burned forests detected in 1996 224 Spatial distribution and intensity (burned areal 625 km2) of burned forests detected in 1996 701W 50M 10° I 1 i . law-mg“ 10%.- f .1; 1] Area of Study 20°s- Burned foreSt area (1996) o 33 Appendix C. 16 I soow Appendix C.17. Spatial distribution and intensity (burned area I625 km2) of burned forests detected in 1999 226 Spatial distribution and intensity (burned area / 625 km2) of burned forests detected in 1999 10°N * 777777 ,, 77 7 a «LV v» e7 M 10°N or a? 8 at Appendix C. 17 227 Appendix C.18. Fractional coverage derived from Landsat imagery acquired in 1992 for the study region 228 Fractional coverage derived from Landsat imagery acquired in 1992 for the study region 5‘5: Tocantins Mato Grosso :.:—Z: 0 250 500 750 1,000 Km Appendix C.18 229 Appendix C.19. Fractional coverage derived from Landsat imagery acquired in 1996 for the study region 230 Fractional coverage derived from Landsat imagery acquired in 1996 for the study I’Jf region A.10apa 1R“\ (“J E/\ / , 11181201338 FC% E10 E = II50 \ - inlamGrosso/ = I— - o 250 500 750 1,000 Km Ax -100 ‘x / \vslji __/ Appendix C.19 231 Appendix C.20. Fractional coverage derived from Landsat imagery acquired in 1999 for the study region 232 Fractional coverage derived from Landsat imagery acquired in 1999 for the study region Jv/ Roraima Amazonas TI 0 o\° IIIIIIIIIflfi 01 o O _I O 0 III—:— 0 250 500 750 Appendix C20 233 Appendix D1 The study region location within the Brazilian Amazon 234 The study region location within the Brazilian Amazon 7o:w 60:W 50°w 5° N 0° 5°s 10°s- 15°s- 70°w 60°W 50°w Appendix D.1. 235 Appendix D.2. Deforestation map for the Brazilian Amazon in 1992, 1996, and 1999 236 Deforestation map for the Brazilian Amazon in 1992, 1996, and 1999 Deforestation map - 1992 Deforestation map - 1999 Appendix D.2 237 Appendix 03. Vegetation map of the Brazilian Amazon in 1999. 238 Vegetation map of the Brazilian Amazon in 1999. 70°W 60" W 50" W forest .-:- 0 300 600 9001km 70° W Appendix D.3 239 10°N Appendix D.4. Map of road network, protected areas, and timber centers in the Amazon 240 Map of road network, protected areas, and timber centers in the Amazon 70° W 60°W 500 W P 1 l l l .,_¥_—.V _50 N 1 5° 3 I! I.151: S l I A Tlmber centers 1 - Protected areas 1 ll 0 250 500 750m 1 S Road network . =—=l ‘ l 20081 #7; A VT in? if T —" " A A. v fi ,_ —.._ A. 2 fihzoos r 1 70° W 60° W 500 w Appendix 0.4 241 Appendix 05. Map of timber volume generated using ordinary kriging interpolation and the dataset derived from forest inventory conducted by RADAMBRASIL project 242 Map of timber volume generated using ordinary kriging interpolation and the dataset derived from forest inventory conducted by RADAMBRASIL project 5°8-1 10°3- . Timber center 1 15° 3'” 7 A ”‘17' v A ’ 1‘ Tlmber Volume h15°S l < 50 m3 ' I - 50-100 m3 1‘ 0 250 500 750 km ‘1 - 1m_150 m3 2008 _777 *‘l __ fifi *7 ‘ ik A. _{_ ‘_ - 150.2m "121.20,, E 1 r - > 200 m S I 70°W 60°W 50'W Appendix D.5. 243 Appendix D.6. Water deficit (mm) for the Brazilian Amazon during the dry season (May to September) in 1999. 244 Water deficit (mm) for the Brazilian Amazon during the dry season (May to September) in 1999. 70°W 60°W 50°w 10° N - . 10°S-W —*'10°S Legend —Paved roads Water deficit '0 300 600 9001 km 20°8- -60.1-80 mm 701w 601w 50°w Appendix 0.6 245 6. References ABlMCl (2002). 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