TA 1 Illflllljfllllll‘llllliil [ 1 3 00882 0288 This is to certify that the thesis entitled WATER QUALITY AND EIOMAss IMPACTS ; OF WATER TABLE MANAGEMENT presented by Andrew Charles Fogiel has been accepted towards fulfillment of the requirements for Technology and Systems Management es flfidq / flpmflr’ [' Date f/C/gz 0-7639 MS U is an Affirmative Action/Equal Opportunity Institution LIBRARY Mlchlgan State Unlverelty i PLACE IN RETURN BOX to remove this checkout from your record. TO AVOID FINES return on or before date due. DATE DUE DATE DUE DATE DUE ‘ l . - 5- 9" i _ | o :1 I T fill J MSU Is An Affirmative Action/Equal Opportunity lnstttutlon , chimeras-9.1 WATER QUALITY AND BIOMASS IMPACTS OF WATER TABLE MANAGEMENT BY Andrew Charles Fogiel A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Department of Agricultural Engineering 1992 ABSTRACT WATER QUALITY AND BIOMASS IMPACTS OF WATER TABLE MANAGEMENT BY Andrew Charles Fogiel Research conducted in 1990 and 1991 evaluated the influences of water table management on (1) the fate of agricultural chemicals in drainage waters, and (2) corn biomass production. The treatments were "subirrigation" (SI), "subsurface drainage" (DO), and "no subsurface drainage" (ND). 1990 had above average seasonal rainfall, and the 1991 had below average seasonal rainfall. Iflfi-N drainage loadings from the SI and DO treatments increased compared to the ND treatment for both growing seasons. The SI treatment reduced Nos-N loadings compared to the DO treatment for both growing seasons. PO4-P drainage loadings from the SI and DO treatments were reduced compared to the ND treatment for above average rainfall. P0,.-P loadings from all three treatments were insignificant for below average rainfall. Plant biomass increased in SI compared to DO and ND during above average rainfall. Plant biomass decreased in SI compared to DO, and increased compared to ND during below average rainfall. ACKNOWLEDGEMENTS I would like to extend my sincere thanks and appreciation to my major professor Dr. Harold Belcher for his guidance and assistance during my research and studies. His dedication towards the water management field provided inspiration and helped strengthen my conviction of working for the improvement of the relationship between agriculture and our environment. I would also like to thank the members of my committee, Dr. Ted London, Dr. George Merva, Dr. Jim Crum, and Dr. Ruth Schaffer, for their guidance, inspiration and support of my research and studies. Finally I want to thank Mr. Roger Gremmel and his family, the farmers who provided practical suggestions and contributions that helped make this research project successful and mutually beneficial. TABLE OF CONTENTS INTRODUCTION . . . . . . . . . . . . . . . . . . . . LITERATURE REVIEW . . . . . . . . . . . . . . . . . . Nutrients . . . . . . . . . . . . . . . . . . . Water Table Management . . . . . . . . . . . . . Effect on Field Runoff . . . . . . . . . . Subsurface Drainage . . . . . . . . . Controlled Drainage and Subirrigation Effect on Pollutants . . . . . . . . . . . Subsurface Drainage . . . . . . . . . Controlled Drainage and Subirrigation Effect on Groundwater Quality . . . . . . . Subsurface Drainage . . . . . . . . . Controlled Drainage/Subirrigation . . Crop Yield . . . . . . . . . . . . . . . . . . . Biomass . . . . . . . . . . . . . . . . . . . . SITE DESCRIPTION . . . . . . . . . . . . . . . . . . METHODOLOGY . . . . . . . . . . . . . . . . . . . . . System Operation and Data Collection . . . . . Meteorological Data . . . . . . . . . . . . . . Water Table Elevation Data . . . . . . . . . . . Drainage Flow Monitoring and Water Sample COlleCtion O O O O O I O O O O O O O O O 0 Soil and Soil Water Collection . . . . . . . . . Agronomic Data . . . . . . . . . . . . . . . . . Statistical Analysis . . . . . . . . . . . . . . iv 10 10 10 11 12 12 26 33 33 35 36 37 40 41 41 43 43 44 47 51 53 RESULTS AND DISCUSSION . . System Operation Data Hydrology . . . . . . Nutrient . . . . . . . Alachlor . . . . . . . Crop Yield and Biomass Statistical Analysis . CONCLUSIONS . . . . . . . . RECOMMENDATIONS . . . . . . REFERENCES . . . . . . . . 57 57 58 69 111 112 119 122 126 207 B. C. D. E. F. APPENDICES Monitoring Equipment Diagram . . . . . . . . Climatological Data . . . . . . . . . . . . Observation Well Watertable Elevation . . . Water Sample Nutrient Analysis Data . . . . Soil Sample Nutrient Analysis Data . . . . Soil Alachlor Analysis Data . . . . . . . . Crop Yield, Leaf Area, Stem Volume and Biomass Nutrient Analysis Data . . . . . . . Soil Nutrient, Crop Yield, Leaf Index and Biomass Statistical Analysis . . . . . . . . vi 128 132 141 148 161 171 173 199 LIST OF TABLES Table 1. Soil texture and classification . . . . . . . Table 2. Fertilizer and herbicide summary . . . . . . . Table 3. Field operations, irrigation and drainage control schedule 1990 . . . . . . . . . . . . . . Table 4. Field operations, irrigation and drainage control schedule 1991 . . . . . . . . . . . . . . Table 5. Monthly drainage discharge volumes . . . . . . Table 6. Rainfall nutrient loadings and concentrations Table 7. Irrigation water nutrients . . . . . . . . . . Table 8. SI tile drainage nutrient concentrations . . . Table 9. DO tile drainage nutrient concentrations . . . Table 10. SI surface drainage nutrient concentrations . Table 11. DO surface drainage nutrient concentrations . Table 12. ND surface drainage nutrient concentrations . Table 13. SI Treatment Monthly Drainage Nutrient Loadings . . . . . . . . . . . . . . . . . . Table 14. DO Treatment Monthly Drainage Nutrient Loadings . . . . . . . . . . . . . . . . . . Table 15. No Drainage (ND) Treatment Monthly Drainage Discharge Nutrient Loadings . . . . . . . . Table 16. Tile drainage ammonia-N concentrations and loadings . . . . . . . . . . . . . . . . . . . . Table 17. Surface drainage ammonia-N concentrations and loadings . . . . . . . . . . . . . . . . . . . . Table 18. Alachlor Loadings and Concentrations in Drainage Water . . . . . . . . . . . . . . . . . vii 42 53 54 55 63 69 71 71 72 78 78 79 81 83 84 101 103 111 Table Table Table Table Table 19. 20. 21. 22. 23. Crop Yield Data . . . Leaf Area Index . . . Plant Biomass . . . . Plant Nutrient Content Corn Kernel Nutrient Content viii 113 116 116 118 119 Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. LIST OF FIGURES Research Site Layout . . . . . . . . . Site rainfall . . . . . . . . . . . . . . Comparison of site rainfall to seasonal average . . . . . . . . . . . . . . . . . Watertable Depths 1990 . . . . . . . . . Watertable Depths 1991 . . . . . . . . . Total Drainage Volumes . . . . . . . . . Tile Drainage Volumes . . . . . . . . . . Surface Drainage Volumes . . . . . . . . Total Drainage Nitrate-N Loadings . . . Tile Drainage Nitrate-N Loadings . . . . Surface Drainage Nitrate-N Loadings . . Total Drainage OrthOphosphate-P Loadings Tile Drainage Orthophosphate-P Loadings Surface Drainage Orthophosphate-P Loadings Total Drainage Potassium Loadings . . . Tile Drainage Potassium Loadings . . . . Surface Drainage Potassium Loadings . . Total Drainage Ammonia-N Loadings . . . Tile Drainage Ammonia-N Loadings . . . . Surface Drainage Ammonia—N Loadings . . Soil Nitrate Nitrogen Loadings, 0.0-0.3m Soil Nitrate Nitrogen Loadings, 0.3-O.6m Soil Nitrate Nitrogen Loadings, 0.6-0.9m Soil Orthophosphate-P Loadings, 0.0-0.3m Soil Orthophosphate-P Loadings, 0.3-0.6m ix 41 58 60 60 61 62 64 68 82 85 87 90 92 94 97 98 100 101 102 104 104 105 105 107 107 Figure 26. Soil Orthophosphate-P Loadings, 0.6-0.9m . 107 Figure 27. Soil Potassium Loadings, 0.0-0.3m . . . . 108 Figure 28. Soil Potassium Loadings, 0.3-0.6m . . . . 108 Figure 29. Soil Potassium Loadings, 0.6-0.9m . . . . 109 Figure 30. Soil Ammonia Nitrogen Loadings, 0.0-0.3m . 110 Figure 31. Soil Ammonia Nitrogen Loadings, 0.3-0.6m . 110 Figure 32. Soil Ammonia Nitrogen Loadings, 0.6-0.9m . 110 Figure 33. Crop Yields . . . . . . . . . . . . . . . 114 INTRODUCTION Water table management is. defined as any practice which includes subsurface drainage, controlled subsurface drainage and/or subirrigation. Such practices provide a means of regulating the water table at optimum depths during periods of both drought and excessive rain. Optimum water table depths are those which provide sufficient amounts of water in the root zone of developing crops in order to satisfy the water requirements. Artificial drainage removes excessive water from the root zone during periods of heavy rainfall providing a suitable environment for developing crops. Drainage also ensures trafficable conditions for field operations. Water table management has been shown to be economically beneficial to Michigan corn and sugar beet producers (LeCureux and Boom, 1989a&b). Controlled drainage/subirrigation systems provide a means of water management for agricultural lands that require both irrigation and drainage for crop production. During drought periods, water is supplied through the drainage system to the root zone of the growing crop. Controlling drainage also allows for the conservation of water added to the field by rainfall. The system operates as a drainage system to remove excessive water from the root zone during wet periods. There is public concern over the environmental fate of 1 2 agricultural chemicals in drainage water. Excessive losses of nutrient and pesticides in drainage are detrimental to the quality of receiving surface water bodies, and adversely affect the surrounding ecology. In addition, mismanagement of agricultural chemicals is a loss of resources. There are many examples in the United States and worldwide of the adverse impacts drainage pollution has on surface and groundwater quality. In the United States, over 30 million hectares of cropland benefit from artificial drainage, with 75 percent in need of drainage system improvement or replacement (USDA, 1987) . Along the Atlantic Coastal regions, the improvement of surface and subsurface agricultural drainage has increased transport of commonly used fertilizer nutrients to adjacent receiving waters (Deal, et al., 1986) Of particular concern are the nitrogen and phosphorus nutrients. The nitrates threaten regional drinking water supplies, and the phosphorus threatens the delicate wetland wildlife. On the Pacific Coast, the San Luis Drainage in The San Joaquin Valley of California is a large water drainage and distribution system which serves most of the agricultural lands and many municipalities in California. High salinity and nitrate contents are commonly found in groundwater beneath irrigated lands, and several chlorinated hydrocarbon pesticides have been detected in numerous wells (Schmidt, et al., 1987). In the north central region, fertilizer use accounts for about 70% of the total annual usage in the United States (Keeney, 1985) and nitrate nitrogen concentrations have been found to exceed the 10 mg/l drinking water standard in many regional groundwater aquifers (Hallberg, 1986). Commonly used herbicides such as alachlor, atrazine, metolachlor and cyanazine have been found in groundwater of several states (Holden, 1986 and Ritter, 1986). The European Community (BC) member nations have experienced an average increase in agricultural productivity per laborer of 7 percent per year over 20 years (Du Vivier, 1986). The EC agricultural policies have led to an intensification of production and increased land values, and the consequences have been increased fertilizer pollution, field drainage, and wildlife habitat destruction (World Resources, 1987) . Funding has been made available to EC member nations for improving agricultural productivity through field drainage. For most of Europe, field drainage is modified or installed in existing agricultural land, but in France, much of the field drainage is for the conversion of wetlands (Baldock, 1984). Within the former Soviet Union, the extent of pollution caused by fertilizer and pesticide runoff in agricultural drainage is staggering. Collective farming practiced in communist nations 4 was often performed on a very large scale. An estimated billion and a half tons of fertile soil are lost to erosion each year, and indiscriminate use of pesticides and fertilizers have poisoned millions of acres of farmland (0.8. News & World Report, 1992). Thirty percent of all foods in the former Soviet Union contain pesticides considered hazardous and are banned in the United States and the European Community. The full extent of the pollution problem and its impacts are far from being realized in the former Soviet Union and other communist block nations since researchers have not until recently been able to investigate and report the full extent of damage caused by agricultural production, and agricultural irrigation and drainage practices. In the United States, the primary nutrient pollutants of concern are nitrates and phosphorus. It was concluded that drinking water containing high nitrate concentrations had the potential of causing methemoglobinemia, a blood disorder in infants that results in adverse health affects and often death (Hammer, M.J., et a1., 1981). The phosphorus anion orthophosphate contributes to algae and aquatic plant growth associated with eutrophication in surface waters. The maximum contaminant level for nitrate nitrogen set by the EPA for drinking water standards is 10 ppm, and a commonly established maximum concentration for orthophosphate phosphorus is 1.0 ppm (Viessman, W.J. , et a1., 1985) . The phosphoric form of orthophosphate phosphorus is the stable form of phosphorus and 5 provides a good starting point for investigating phosphorus reactions in soils (Lindsay, 1979). The 1986 amendments to the Safe Drinking Water Act required that maximum contaminant levels of highly water-soluble pesticides be enforced within three years of enactment. Examples of such pesticides are alachlor, atrazine, simazine and carbofuran (Cook, 1989). The maximum contaminant levels proposed for alachlor, atrazine and carbofuran are 2, 3tand 40 ppb, respectively (Benson, 1989). Michigan has 7.9 million acres of Class I through III cropland, and over 3 million acres requires drainage in order to be productive (USDA, 1982). Within a five county area near the Saginaw Bay of Lake Huron, over 1.6 million ha of land in Michigan has the potential to utilize water table management systems (Kittleson, et al. , 1990) . This has resulted in increased concern as to the potential impact these systems may have on the environment. Scientists at Michigan State University have been conducting field research on the effects of subirrigation.on nutrient and pesticide concentrations and loadings in discharge waters and soil water since April, 1987 (Protaswiewicz, et a1., 1988). The Unionville site, the subject of this thesis, is located in the thumb region of Michigan and within 1 km of the Saginaw 6 Bay. The water table management system was installed during the summer of 1989 by members of the Michigan Land Improvement Contractors Association. The 13.1 ha site is on soils representative of the soils and topography most likely to be subirrigated in Michigan and the North Central Region of the United States. The objective of the Unionville Site project is to evaluate and demonstrate the influences of water table management practices on the environmental fate of agricultural chemicals, with emphasis on nitrogen.and phosphorus, for a soil type with potential for subirrigation expansion. The effect of water table management practices on crop biomass production was also evaluated. The specific objectives are to: To compare the chemical concentrations and loadings in the soil and drainage waters, and compare the corn biomass production, corn leaf, stem and kernel nutrient content of a "subirrigation / controlled drainage" treatment, a "conventional subsurface drainage" treatment, and a "no subsurface drainage" treatment during growing seasons with both above and below average seasonal rainfall. LITERATURE REVIEW Nutrients As stated previously, the main nutrient pollutants of concern are nitrates and the phosphorus anion orthophosphate. Nitrogen is one of many components that are essential for plant growth processes. The amount of nitrogen in available forms for plants is small, while the annual requirements by crops is relatively large“ Often. excessive amounts of nitrogen in readily soluble forms are lost through drainage waters in high quantities creating the potential for surface and groundwater pollution. It can also be lost from the soil by volatilization. The three major forms of nitrogen in mineralsoils identified by Brady (1984) are organic nitrogen associated with the soil humus, ammonium nitrogen fixed by certain clay minerals, and soluble inorganic ammonium and nitrate compounds. Many complex. transformations accompany the intake and loss of nitrogen in soils through the courseaof'a‘yearu These changes occur due to the interlocking succession biochemical reactions in what is known as the nitrogen cycle. Plants absorb most of their nitrogen in the ammonia or nitrate forms. Nitrate is usually the predominant source of nitrogen due to usual higher concentrations in the soil and its ability to freely move to the roots by mass flow and diffusion (Brady, 1984). 8 Much of the nitrogen in a soil is in organic combinations, is protected from loss and is mostly unavailable to plants. Nitrogen is tied up in organic forms by the process of immobilization. The slow release of nitrogen occurs with the conversion of organic to inorganic nitrogen through the process of mineralization. Both the organic and inorganic soil fractions can fix ammonia in forms relatively unavailable to plants and even microorganisms. Many different mechanisms and compounds are involved in the fixation process. Fixation occurs by clay minerals and organic matter. Microorganisms in the soil cause the process of nitrification which is the enzymatic oxidation of ammonia to nitrates. Nitrification occurs at a rapid rate under warm temperature, aerated soil, and moist conditions. Nitrate nitrogen, whether added by fertilizers of formed by nitrification, has four possible fates (Brady, 1984) . It may (1) be incorporated into microorganisms, (2) assimilated into plants, (3) lost to drainage, and (4) escape in a gaseous state. In poorly drained soils with low aeration, nitrates are subjected to reduction by the process of denitrification. The reduction products include nitrogen gases which can be lost to the atmosphere. This reduction occurs primarily through microbial action, although some chemical reduction occurs. Phosphorus is as critical in agricultural crop production as 9 nitrogen. In soils, both inorganic and organic forms of phosphorus occur and both are important to;plants~ 'The amount of phosphorus available for plant use at any given time is very low, seldom exceeding 0.01% of the total phosphorus in the soil (Brady, 1984). The requirements of the plants are supplemented through fertiliZing, but much of what is applied is converted to the less available inorganic forms. In the inorganic form, phosphorus is released very slowly and is usable to plants over a period of years. The retention of phosphorus is viewed as a continuous sequence of precipitation, chemisorption, and adsorption. With phosphorus generally remaining at low concentrations in the soil, adsorption appears to be the dominant retention mechanism (Tisdale, et a1., 1985). Precipitation of many reaction products often occurs with the addition of common phosphoric fertilizers. Due to the variety of chemical properties of fertilizer salts and their mixtures, a great diversity of compounds in soil systems is to be anticipated (Tisdale, et a1., 1985). Phosphorus held at the surface of a solid is said to be adsorbed. When phosphorus penetrates more or less uniformly into the solid.phase, it is considered to be absorbed or chemisorbed (Tisdale, et a1., 1985). Potassium is another vital plant nutrient. Potassium activates numerous enzymes that are responsible for such plant processes as energy metabolism, starch synthesis, nitrate 10 reduction, and sugar degradation. Most mineral soils are relatively high in total potassium. But the quantity of potassium held in an easily exchangeable condition at any given time is usually very small. Most of potassium is held rigidly as part of the primary minerals or is in fixed forms that are moderately available to plants (Brady, 1984). Factors that affect the amount of potassium fixed include (a) the nature of the soil colloids, (b) wetting and drying, (c) freezing and thawing, and (d) the presence of excess lime. .Annual losses of available potassium by leaching and erosion are much higher than those of nitrogen and phosphorus. Water Table Management Effect on Field Runoff Subsurface Drainage The effects of subsurface drainage on field runoff show that subsurface drainage reduces overland flow from fields as compared to similar fields that do not have subsurface drainage. However, the overall water that leaves fields is increased. The predominant flow to the edge of field from a subsurface drainage syStem is in subsurface drain flow. But subsurface drainage . system design, climatological, geographical and soil conditions were all found to influence the rate of flow from a field. 11 Willard, et al. (1927), Schwab and Fouss (1967) Schwab, et al. (1977), Bengtson, et-al. (1984 & 1988), Istok and Kling (1983), Jacobs and Gilliam (1985), Bottcher, et al. (1981), Skaggs, et al. (1982), and Evans and Skaggs (1989) reported that overland flow was reduced by subsurface drainage compared to fields with no subsurface drainage. However, these same studies along with Schwab, et al. (1980) reported that the overall drainage to edge of field was increased by subsurface drainage, and that more water is removed from a field or treatment by subsurface drains than by surface drains. This observation was also reported by Natho-Jina, et al. (1987), Jackson, et a1. (1973), Evans, et al. (1984), and Fouss, et al. (1987). Only Gambrell, et al. (1975) reported higher surface drainage volumes than subsurface drainage volumes from a field. Controlled Drainage and Subirrigation Controlled subsurface drainage and subirrigation has been shown to reduce total subsurface drain flow of conventional subsurface drained fields. The effectiveness of controlling overland flow by controlled drainage and subirrigation systems was dependent upon field characteristics and climatological factors. Research on the effects of controlled subsurface drainage and subirrigation have on field runoff is recent and the data is limited. Campbell, et al. (1985), Gilliam and Skaggs (1986), Deal, et 12 al. (1986), Fouss, et al. (1987), and Evans and Skaggs (1989) reported that controlled drainage and subirrigation system design and management has a significant impact on the drainage flow. from agricultural fields. Campbell, et al. (1935) reported a decrease in surface drainage to edge of field from a subirrigation system compared to a water furrow system, but that the total drainage was increased by the subirrigation system. Gilliam and Skaggs (1986), and Deal, at al. (1986) both reported. that controlled. drainage compared. to conventional subsurface drainage increased surface drainage to edge of field but that the total drainage was reduced. Fouss, et al. (1987) also reported that controlled drainage reduced the total drainage to edge of field compared to conventional subsurface drainage. Evans and Skaggs (1989) reported that total drainage to edge. of field was reduced by controlled drainage compared to conventional subsurface drainage, but system design and management of controlled drainage affected the amount of surface drainage to edge of field. Effect on Pollutants Subsurface Drainage Subsurface 'drainage reduces erosion and sediment bound nutrient losses, mainly phosphorus and potassium, by primarily reducing overland 'flow. Nitrogen losses, particularly nitrate-nitrogen, were generally increased in both overland and subsurface drain flow of subsurface drained fields compared to non drained fields, but system design and field 13 characteristics influence greatly the fate of nitrate-nitrogen transport. Pesticide losses have been cited to be decreased with subsurface drainage, but there is very little data reported to be able to support any firm conclusions on the effect subsurface drainage has on the transport of pesticides. In the Istok and Kling (1983) study on the effects subsurface drainage had on overland flow from.a‘watershed, the effects on suspended-sediment loads transported to the edge of field were simultaneously studied. The principle soil series within the watershed is Willakenzie silt loam, a member of the fine-silty mixed mesic Ultic Haploxeralfs. These soils are moderately deep well—drained deposit of silty material overlying either a palesol or weathered tuffaceous sandstone. The watershed had no subsurface drainage for the first two years of the study, and then was subsurface drained the last two years of the study. A reduction in watershed (overland) sediment loss of approximately 55% was observed on ’ the watershed after the subsurface drainage system was installed. The authors concluded that the reduction in sediment loss was caused by the reduction of watershed runoff observed in the study. The Schwab, Nolte and Brehm (1977) study of the effects subsurface drainage had on total flow from a field also 14 studied the effects on sediment transport (erosion) from a field. Three treatments compared were no subsurface drainage, subsurface drainage only, and combination surface and subsurface drainage. ‘The treatments were located in a predominantly Toledo silty clay lakebed soil. The no subsurface, drained treatment had annual average sediment transport to edge of field of 3687 kg/ha. The subsurface drained only treatment had annual average sediment transport to edge of field of 2539 kg/ha. The combination treatment had annual average sediment transport to edge of field of 2672 kg/ha. The authors concluded that subsurface drainage reduced soil transport due to the reduction in overland flow measured. Skaggs, 'Nassehzadeh-Tabrizi and Foster (1982) coupled the drainage simulation model DRAINMOD with the CREAMS model for simulating erosion and evaluating the effects of combination subsurface/surface drainage systems on erosion. The simulations were performed on a Goldsboro sandy loam (fine- loamy, siliceous, thermic Aquic Paleudults). Changing the drainage system from one with good surface drainage and poor subsurface drainage to one with poor surface drainage and good subsurface drainage caused predicted average annual rates of erosion to be reduced from 9 to 0.9 metric tons/ha. Increasing the subsurface.drain depth from 0.75 m‘to 15 1.25 m for a drain spacing of 30 m reduced predicted erosion over a 5-year period from 33 to 23 metric tons/ha. The authors concluded that the reduction overland flow observed had reduced erosion. Schwab, Fausey and Kopcak (1980) studied the effects subsurface drainage has on sediment, nitrate-nitrogen, phosphorus and potassium transport to edge of field from the same three drainage treatments used to study the effects on flow. The no subsurface: drainage treatment. had. annual average sediment losses of 2548 kg/ha. The deep subsurface drainage only treatment had annual average sediment loss of 1529 kg/ha. The no subsurface drainage treatment had an annual average nitrate-nitrogen carried to edge of field of 12.1 kg/ha with annual mean concentrations of 3.4 ppm ranging from 0.4 to 11 ppm. The deep subsurface drainage only treatment annual average nitrate-nitrogen carried to edge of field of 18.7 kg/ha, with annual mean concentrations of 8.2 ppm ranging from 5.0 to 23.0 ppm. The annual average phosphorus carried to the edge of field from the no subsurface drainage treatment was 2.2 kg/ha, with annual mean concentrations of 0.9 ppm ranging from 0.4 to 2.0 ppm.- The deep subsurfaCe drainage only treatment had annual 16 average of phdsphorus carried to edge of field of 1.2 kg/ha, with annual mean concentrations of 0.7 ppm ranging from 0.5 to 1.0 ppm. The annual average potassium Carried to edge of field from the surface drainage only treatment was 31.6 kg/ha, with annual mean concentrations of 22.0 ppm ranging from 6.0 to 34.0 ppm. The deep subsurface drainage only treatment had annual average potassium carried to edge of field of 22.5 kg/ha, with. annual mean concentrations of 14.2 ppm ranging from 3.0 to 26.0 ppm. The authors concluded that subsurface. drainage caused. a decrease in sediment, phosphorus, and potassium carried to edge of field, while-nitrate-nitrogen was increased. In the Bengtson, Carter, Morris and Bartkiewicz (1988) study of subsurface drainage effects on flow to edge of field, the effects on sediment, nitrogen and phosphorus carried to edge of field were also studied. The annual average total soil carried to edge of field from the treatment without subsurface.drains and.the treatment with subsurface drains was 4986 and 3482 kg/ha, respectively. Of the 3482 kg/ha of total soil carried from the subsurfacetdrain treatment, 3117 kg/ha was from.overland flow and 365 kg/ha.was from subsurface drain flow. The annual average total ammonia and nitrate-nitrogen (total 17 nitrogen) carried to edge of field from the treatment without subsurface drains and the treatment with subsurface drains was 7.3 and 6.0 kg/ha, respectively. Of the 6.0 kg/ha of total nitrogen carried to edge of field from the subsurface drain treatment, 4.2 kg/ha was from overland flow and 1.8 kg/ha was from subsurface drain flow. The annual average total phosphorus carried to edge of field from the treatment without subsurface drains and the treatment with subsurface drains was 7.8 and 5.0 kg/ha, respectively. Of the 5.0 kg/ha of total phosphorus loss from the subsurface drain treatment, 4.7 kg/ha was from overland flow and 0.3 kg/ha was from subsurface drain flow. The authors concluded that sediment loss was reduced by subsurface drainage primarily due to reduced overland flow. It was thought that nitrogen transport was restricted by a dense clay layer in the top meter of the soil profile, typical of the local Mississippi flood plain and reduced nitrogen carried to edge of field from the subsurface drained plots. Phosphorus 10sses were observed to be influenced mainly by time after application of phosphorus fertilizer, monthly amount of sediment loss, rainfall amounts, amount of surface runoff and drainage discharge. Bdttcher, Monke and Huggins (1981) studied the effects subsurface drainage had on sediment, nutrient and pesticide 18 transport to edge of field from the 17 ha subsurface drainage system used to study the effects of subsurface drainage on flow to edge of field. The annual average sediment carried to edge of field from the subsurface drained treatment was 94 kg/ha. Annual average total phosphorus and nitrate-nitrogen carried to edge of field were 0.2 and 6.5 kg/ha, respectively. Annual mean phosphorus and nitrate-nitrogen concentrations of 0.28 and 7.5 ppm, respectively. The authors concluded through comparing the subsurface drained treatment to a more normal situation with partial subsurface drainage and greater overland flow, the total sediment losses and sediment-bound nutrient loadings were substantially less, but not data of the :more normal drainage treatment was presented. Nitrate-nitrogen and other soluble nutrients were higher in the overland flow of the subsurface drained treatment. Overland flow had a direct impact on sediment and sediment bound nutrient loadings. The Jacobs and Gilliam (1985) study of the effects subsurface drainage had on flow from field also studied the fate of nitrogen carried by drainage flow through examining measured nitrate concentrations in shallow groundwater beneath cultivated fields and in the overland drain flow from those fields. Nitrate-nitrogen losses in subsurface drain flow and overland flow were estimated using DRAINMOD for a Middle 19 Coastal Plain watershed. The natural stream and no improved drainage treatment fields had mean nitrate-nitrogen concentrations in subsurface wells of 7.6 ppm (mg/l) . The mean nitrate-nitrogen concentration in the overland flow at the edge of the fields was measured to be 1.1 ppm. The estimated annual nitrate-nitrogen carried by overland flow at the edge of the fields was 1.0 kg/ha. The surface ditch treatment had a measured mean nitrate- nitrogen concentration from subsurface wells of 7.7 ppm and an estimated annual 9.9 kg/ha carried in subsurface flow. The mean nitrate-nitrogen concentration measured in overland flow at the edge of the field was 1.7 ppm and an estimated annual 3.8 kg/ha carried-in overland flow. The subsurface drain treatment had a mean nitrate-nitrogen concentration measured from the subsurface drain flow of 14.8 ppm with an estimated annual 54.9 kg/ha carried in subsurface drain flow. The mean nitrate-nitrogen measured from overland flow at the edge of the field was 1.2 ppm with an estimated annual 0.3 kg/ha carried in overland flow. The authors concluded that subsurface drainage caused more nitrate-nitrogen to be carried to edge of field. The highest amounts were carried insubsurface drain flow. Subsurface drainage caused a reduction in nitrate-nitrogen carried in 20 overland flow. In the Jackson, Asmussen, Hauser and White (1973) study, nitrate-nitrogen carried to edge of field was monitored in both the overland and subsurface drain flow from a subsurface drainage system. Water samples from both overland flow and subsurface drain flowmwere collected during each natural rainfall event that.caused overland.and subsurface:drain flow. Water samples taken from the site before any agricultural practices were initiated showed appreciable nitrate-nitrogen concentration. The total annual average nitrate-nitrogen carried to edge of field was 43.64 kg/ha, with 0.30 kg/ha by overland flow and 34.34 kg/ha by subsurface drain flow. The authors concluded that the high proportion of nitrate-nitrogen carried in the subsurface drain flow can be accounted for by the high leaching potential of the sandy soil. Baker, Campbell, Johnson and Hanaway (1975) made measurements of nitrate-nitrogen, sulfate, orthophosphate, and total phosphorus concentrations and loads carried to edge of field from four subsurface drained plots 0.42, 0.46, 0.41 and 0.46 ha in size, at a study site in Iowa from 1970 to 1973. The soil type was a silty loam with a maximum slope of 2%. Average subsurface flow for all four plots was measured on a 21 daily basis for the individual flow periods. The average daily flow ranged from 0.05 to 2.62 mm/day’. The annual average nitrate-nitrogen carried to edge of field by subsurface (drain flow was 30.6 kg/ha. The mean nitrate- nitrogen concentration in subsurface drain water for individual flow'periods was 21.0 ppm, ranging from.8.2 to 36.2 ppm . The annual average orthophosphate carried to edge of field by subsurface drain flow was 0.003 kg/ha. The mean orthophosphate concentration in subsurface drain water for individual flow periods was 5 ppm, ranging from 2 to 13 ppm. The annual average total phosphorus carried to edge of field by subsurface drain flow was 0.018 kg/ha. The mean total phosphorus concentration in subsurface drain water for individual flow periods was 24 ppm, ranging from 16 to 103 ppm . The authors concluded that nitrate-nitrogen concentrations increased with increased flow to end of field from rain events. But similar intensity events did not yield similar amount of nitrate-nitrogen.> 'This was accounted for by differences of nitrate-nitrogen concentrations in the water that passed through the soil profile, soil moisture conditions, depth and amount of organic matter, temperature, tillage, and timing and amounts of fertilizer applied. 22 Willardson, Meek, Grass, Dickey and Bailey (1972) studied the process of denitrification in an agricultural field by the submergence of drains in the San Joaquin Valley of California. The soil around the subsurface drains, groundwater from the center of the experimental field, and subsurface drainage flow were tested for nitrate-nitrogen concentrations. The highest nitrate-nitrogen readings ranging from 330 to 364 ppm were found in the soil around the bottom.of the subsurface drains while the soil at the top of the drains had lower readings ranging from .10 to 218 ppm. The highest concentrations found in all measurements were around the drains. While nitrate-nitrogen concentrations remained the same over a measured period of time, subsurface drain flow concentrations decreased over the same period. From this data, the authors concluded that denitrification was occurring. Benoit, Grant, Bornstein and Hepler (1989) measured concentrations of carbon and nitrogen in subsurface drain flow from different subsurface drainage plots to study the long- term changes in soil carbon and nitrogen, and- determine nitrogen levels in soil water and subsurface.drain flown Each plot was 36 x 36 m (118 x 118 ft) and located on a poorly drained silty clay loam soil in Maine. Measurements were made from 1978 through 1983. Three treatments were studied. The first treatment was three plots with subsurface drains spaced 23 3 m, the second treatment was three plots with subsurface drains spaced 6 m, the third treatment was three plots with subsurface drains spaced 12 m, and the forth treatment was three plots with no drains. Data graphically presented showed that subsurface drainage caused a decrease in organic carbon and loss of nitrogen in the 0- to 0.15-m soil layer. Nitrate-nitrogen concentrations in subsurface drain flow averaged as high as 33 ppm (range of 29-36 ppm) for all drain spacings. in. July of 1980 but decreased to less than 1 ppm by November of 1984. The authors concluded that long term potential for nitrogen loss to overland or subsurface drain flow fromtdrainage of these soils was small, and that proper management of cropping and fertilizer practices can keep the potential at minimum. The model Kanwar, Johnson, and Baker ( 1983) developed to simulate the major water processes occurring in a typical agricultural watershed also simulated the nitrogen-transport processes. The measured and predicted nitrogen carried by subsurface drain flow was 30.84 and 30.47 kg/ha. The model provided satisfactory simulation results. Differences between measured and predicted values were caused by lack of a completely accurate hydrologic predictions. The authors concluded that the processes of nitrification, mineralization, nitrogen 24 uptake, and denitrification are areas that need to be better investigated for better representation. Muir and Baker (1976) monitored the herbicides cyanazine, cyprazine, atrazine, and metribuzin which were applied separately to four subsurface:drained.experimental plots 1.75, 1.16, 1.30 and 0.60 ha in size, located in southern Quebec, Canada, from 1973 to 1974. ,Initial levels of atrazine and its degradation products were detected in subsurface drain flow from all four plots before pesticide applications were made. Atrazine had been used on a yearly base since 1968. Atrazine concentrations from the subsurface drain water ranged from 0.30 to 1.49 ppb (pg/l), 0.00 to 0.68 ppb for cynazine, and 0.00 to 0.57 ppb for cyprazine. Metribuzin was applied during the second year and was found in the subsurface drain water in concentrations ranging from 0.00 to 1.65 ppb. Atrazine levels 'were consistently’ higher' than all other herbicides because of residuals left from. previous applications“ lOverall analysis showed that about 0.15% of the applied chemicals appeared in the subsurface drain water either in the unchanged form or as degradation products. southwick, et a1. (1990) measured atrazine and metolachlor carried in subsurface drain flow over a period of 243 days. The herbicides were applied preemergent to corn grown on subsurface drained treatment plots, and on undrained treatment 25 plots. The subsurface drainage treatment consisted of three 4 ha (9.9 ac) and, two 2 ha (4.9 ac) plots. The no subsurface drain treatment plots consisted of two 4 ha (9.9 ac) and, two 2 ha (4.9 ac) plots. The plots were located on a clay loam near Baton Rouge, Louisiana. Atrazine was applied at a rate of 1.63 kg/ha, and a total of 0.00623 kg/ha was measured in subsurface drain flow. Metolachlor was applied at a rate of 2.16 kg/ha, and 0.02760 kg/ha was measured from subsurface drain flow. Concentrations for atrazine ranged from 0.015 ppb (243 days after application) to 3.53 ppb (12 days after application). Concentrations for metolachlor ranged from 1.92 ppb (58 days after application) to 29.3 ppb (12 days after application). All of the metolachlor carried in the subsurface drain water was observed within the first 59 days after application. Bengtson, et al. (1990) reported on the amount of metolachlor and atrazine carried to edge of field from a subsurface drained treatment and in flow from the no subsurface drainage treatment over a 243 day period. The total amount of atrazine and metolachlor measured in flow to edge of field from the subsurface drainage treatment was 0.02347 kg/ha and 0.02584 kg/ha, respectively. The total amount of atrazine and metolachlor measured in overland flow to end of field from the no subsurface drain treatment was 26 0.05164 kg/ha and 0.05268 kg/ha, respectively. Subsurface drainage reduced. the amount. of atrazine and. metolachlor carried to end of field. Smith, et al. (1990), reported.on the movement of atrazine and alachlor within the soil profile and a shallow water table aquifer following surface application. Concentrations of atrazine in the soil water at a depth of 0.61 m reached 350 ppb 19 days after application, but no alachlor was detected in the soil below a depth of 0.36 m. Atrazine concentrations as high as 90 ppb were found in the shallow ground water six months after application while no alachlor was detected. Protasiewicz, et al. (1988), reported to the MiChigan Department of Natural Resources the results of a 1 year water quality pilot study from 1987 to 1988. Atrazine carried to the edge of field by the subsurface drain flow from the conventional subsurface drainage treatment was 0.00126 kg/ha. The maximum concentration of atrazine observed in the subsurface drain water was 0.8 ppb. antroll d Drainage and Subirrigation Properly designed and managed controlled drainage and subirrigation systems have. the potential to reduce .the transport of accumulative plant nutrients and applied herbicides. ‘In addition to design and management factors, site characteristics influence the fate of transport of 27 nutrients and applied herbicides. No data was provided on the sediment transport in controlled drainage and subirrigation systems and little has been reported On the fate of potassium transport. Gilliam, Skaggs and ‘Weed (1979) compared the amount of nitrate-nitrogen carried to edge of field from conventional drainage and controlled drainage treatments. Controlled drainage was maintained by using flashboard riser-type water level control structures installed at two locations representative of soil conditions of large areas of artificially drained soils of the North Carolina Coastal Plain, both well and poorly drained. Each location had 2 fields, one which was under conventional drainage while the other was under controlled drainage. The treatments of each field were changed periodically. Nitrate-nitrogen reductions in subsurface drain flow from an average 32.5 to 4 kg/ha by controlling subsurface drainage in the moderately well drained soils was observed. The nitrate- nitrogen concentrations tended to be a constant 15-20 ppm year round. In the moderately well drained soils, there was no sign of increased denitrification. The average total nitrate-nitrogen carried to edge of field from the conventional drainage treatments was 27.5 kg/ha and slightly half that was found at the edge of field for the 28 controlled drainage treatments in the poorly drained soils. The authors concluded this reduction was due to increased water movement into and through deeper soil horizons which underwent denitrification. High water table control could have a long-term effect on structure in some soils but this phenomena was not studied. The Campbell, Rogers, and Hensel (1985) study on flow to edge of field from a subsurface drainage-irrigation system with drainage control and a water furrow-irrigation system also studied nutrient transport to edge of field from.both systems. Nitrate-nitrogen losses were the predominant nitrogen form detected from.both.systems, and.orthophosphate was:measured.as well. The total nitrate-nitrogen carried to edge of field from the water furrow system was 4.53 kg/ha. The total nitrate- nitrogen carried to edge of field was 2.75 kg/ha, with 0.83 kg/ha carried in overland flow. and 1.91 kg/ha carried in subsurface drain flow. The total orthophosphate carried to edge of field from the furrow system was 1.10. The total orthophosphate carried to edge of field was 0.43 kg/ha, with 0.26 kg/ha carried in overland flow'and 0.17 kg/ha carried in subsurface.drain flow. The greater loss of nitrate-nitrogen in the water furrow 29 system was unexpected by the researchers. The authors concluded that the combining of a controlled high water table and raised row-beds created conditions resulting in interflow through the row-beds to the alleys instead of leaching downward to the drains. Gilliam and Skaggs (1986) determined the effects of drainage system design and management upon water quality of drainage water through use of the DRAINMOD computer model on two experimental Atlantic Coastal Plain soils. Nitrate-nitrogen loads carried to edge of field were compared between conventional drainage treatments and controlled drainage treatments. The annual average nitrate—nitrogen carried to edge of field from the conventional drainage treatments was 33.5 kg/ha. The annual average nitrate-nitrogen carried to edge of field from the controlled.drainage treatments was 22.8 kg/han ‘The annual average phosphorus carried to edge of field from the conventional drainage treatments was 0.12 kg/ha. The annual average phosphorus carried to edge of field from the controlled drainage treatments was 0.22 kg/ha. Controlled drainage reduced the nitrate-nitrogen carried.to edge:of field but increased the phosphorus carried to edge of field. Deal, Gilliam, Skaggs and Konyha (1986) used the DRAINMOD computer simulation to predict nutrient losses under various 30 drainage designs from 6 different soils over a 20 year period. Nitrate-nitrogen and total phosphorus carried to edge of field from conventional drainage treatments and controlled drainage treatments were compared. The predicted annual average nitrate-nitrogen carried to edge of field from the conventional drainage treatments was 19.30 kg/ha, with 1.42 kg/ha in overland flow_and 17.88 kg/ha in subsurface drain flow; The predicted annual average nitrate- nitrogen carried to edge of field from the controlled.drainage treatments was 14.49 kg/ha, with 1.93 kg/ha in overland flow and 12.56 kg/ha in subsurface drain flow. The annual average total phosphorus carried to edge of field from the conventional drainage treatments was 8.30 kg/ha, with 1.60 kg/ha in overland flow and 6.70,kg/ha in subsurface drain flow. The annual average total phosphorus carried to edge of field from the controlled drainage treatments was 8.00 kg/hg, with 2.00 kg/ha in overland flow and 6.00 kg/ha in subsurface drain flow. Controlled drainage reduced nitrate-nitrogen'and phosphorus carried.to end.of field, but increased.both amounts carried to edge of field by overland flow. Skaggs and Gilliam (1981) modified the computer simulation model, DRAINMOD to predict nitrate-nitrogen movement from artificially’ drained soils ‘with. high. water ‘tables. Conventional drainage, controlled drainage during the winter 31 and controlled drainage all year were simulated for both good and poor surface drainage systems. The good surface drainage system had predicted nitrate- nitrogen carried to edge of field from the conventional subsurface drainage treatment of 20.0 kg/ha. Nitrate-nitrogen carried to edge of field from the controlled drainage treatment was 14.5 kg/ha for controlled drainage during the winter, and 12.2 kg/ha for controlled drainage all year. The poor surface drainage system had predicted nitrate- nitrogen carried to edge of field from the conventional drainage treatment of 38.9 kg/ha. Nitrate-nitrogen carried to edge of field from the controlled drainage treatment was 33.0 kg/ha for controlled drainage during the winter, and 39.0 kg/ha for controlled drainage all year. The Evans and Skaggs (1989) study on the effects water table management strategies have on flow to edge of field also studied average annual nitrate-nitrogen and total phosphorus carried to edge of field. Subsurface drain and overland flow were compared between conventional and controlled drainage treatments. The average annual nitrate-nitrogen carried to edge of field from the conventional drainage treatments was 35.0 kg/ha, with 8.5 kg/ha in overland flow and 26.5 kg/ha in subsurface drain 32 flow; “The annual mean concentrations were 3.0 ppm in overland flow and 8.7 ppm in subSurface drain flow. The average annual nitrate-nitrogen carried to edge of field from the controlled drainage treatments was 18.7 kg/ha, with 4.5 kg/ha in overland flow and 14.2 kg/ha in subsurface drain flow; ‘The annual mean concentrations were 2.6 ppm in overland flow and 6.8 ppm in subsurface drain flow. The average annual total phosphorus carried to edge of field from the conventional drainage treatments was 0.69 kg/ha, with 0.48 kg/ha in overland flow and 0.21 kg/ha in subsurface drain flow. The annual mean concentrations were 0.14 ppm in overland flow and 0.05 ppm in subsurface drain flow. The average annual total phosphorus carried to edge of field from the controlled drainage treatments was 0.45 kg/ha, with 0.28 kg/ha in overland flow and 0.17 kg/ha in subsurface drain flow. The annual mean concentrations were 0.12 ppm in overland flow and 0.07 ppm in subsurface drain flow. In the Protasiewicz, et al. (1988), report to the Michigan Department.of Natural Resources, the total atrazinelcarried.to the edge of field by the subsurface drain flow from the subirrigation treatment was 0.00277 kg/ha. The maximum concentration observed in the subsurface drain water was 1.8 ppb. The subsurface drain atrazine loading from the subirrigation treatment was 120% greater' than from the 33 conventional subsurface drainage treatment. Effect on Groundwater Quality Subsurface Drainage Little published studies are available that look at the effects subsurface'drainage practices have on groundwater quality. The cost of studying groundwater aquifers is high and studies are focused more on impacts to surface water quality. Only until recent growth in concern of groundwater aquifer contamination has created a demand to research the impacts of subsurface drainage on groundwater quality. Many of the studies cited describe the potential problems that exist under agricultural practices and the needs of investigating agricultural water management practices. But for most soils that are drained, a low'permeable soil protects the deeper groundwater aquifers that are used by the public. Schmidt and Sherman (1987) summarized numerous research findings on the effects of irrigation and on groundwater quality in California. ' The authors concluded that contamination of groundwater aquifers by nutrients and pesticides is dependent on. the soil structure ‘within a prOfile. The presence of sandy soils and shallow groundwater was found to contain the highest amounts of pesticides and nitrate levels. Where hardpans were present, no significant amounts of pesticides and nutrients used in agricultural production have been found. 34 Mossbarger and Yost (1989) reviewed available case studies from the Central Sand Plain of Wisconsin and discussed present and potential problems associated with irrigation and groundwater quality. These soils are characteristically low in moisture holding capacities where heavy irrigation and applications of herbicides and pesticides are practiced in order to achieve substantial crop yields. .Because of the high hydraulic conductivities and leaching potential of sandy soils, shallow groundwater aquifers in these areas are extremely susceptible to contamination of soluble nutrients and pesticides. Pivetz and Steenhuis (1989) investigated pesticides, nitrates and tracers carried to edge of field from subsurface drains and to the groundwater from 1987 to 1989, in northern New York. The site was located.on.a predominantly sandy clay loam and clay loam soil overlying a profile of clay on top of gravelly loam and sandy loam. The profile was on top of bedrock, 9 m deep. Potential of contamination of underlying groundwater aquifers was thought to be minimal. The results from the non-refereed American Society of Agricultural Engineers paper so far have found no significant traces of pesticides in deep groundwater well samples. Nitrates were detected in deep groundwater well samples and exceeded the 10 ppm maximum contamination level ion 2 occasions. 35 Users of chemicals should understand the factors that influence the movement of a chemical through a soil profile. The characteristics of the chemical, frequency of application, type of soil and depth of water table are crucial in preventing possible contamination of groundwater (Michigan State University, 1988). Controlled DrainagelSublrrigation Few published studies are available that look at the effects water table management practices have on groundwater quality. Ritter, Humenik, and Skaggs (1990) reviewed the effects irrigated agricultural has on groundwater quality through out the northeastern and Appalachian states. The largest irrigated areas are located.in.North Carolina, New Jersey, New York, Delaware, Virginia, and Maryland, most of which is on Coastal Plain soils. These soils are typically sandy loam or loamy sand and are highly susceptible to leaching of soluble materials, especially after heavy rainfalls. The authors cited the studies of water table management performed. in INorth. Carolina. that. have. shown significant reduction in nitrate-nitrogen entering surface waters under controlled drainage. But little research has been performed to determine the fate of soluble materials, especially Car a 5' DCE‘ grow that yste 36. pesticides and nitrate-nitrogen through sandy soils into underlying groundwater aquifers. Crop Yield Carter, et al. (1988) found increased sugarcane yields under a subirrigation and controlled drainage system compared to a non-irrigated and surface drained only system. The benefits to sugarcane yield from water table management were most significant during periods of drought. Foust, et al. (1987) observed maximum corn silage yields from fields with controlled subsurface drainage during a growing season with below normal rainfall and minimum yields during above normal growing season rainfall. Evans and Skaggs (1989) emphasized that properly designed and operated water table management systems can significantly increase yields and. production efficiency compared to conventional subsurface drainage and no subsurface “drainage. Mismanaged controlled drainage and subirrigation systems can significantly reduce crop yield and quality. Belcher (1990) reported that corn and soybean production is sensitive to mean water table depth and water table fluctuation. Research found that the best Operation management for subirrigation of crops is to establish a water table depth immediately following seeding. The water table should be raised periodically'for short time periods during the growing season. At crop maturity, the system should be 37 put into the subsurface drainage mode and maintained until after harvest. It was found to be beneficial to repeat the water table management cycle the next spring. Sipp, et al. (1984) reported in an unpublished paper that corn yields increased substantially under water table management compared to a non-drained and non-irrigated conditions. Rausch.and Nelson (1984) reported in an unpublished paper that subirrigation increased alfalfa production during the months of July and August compared “to non-irrigated treatments. Carter, et al. (1988) found and reported in an unpublished paper that water table depths maintained within 0.30 m of the surface adversely affected soybean, wheat, and corn yields, but did affect the quality of the crops. Lieualse Publication of research on biomass production is limited to observed effects environmental and climatological stresses have on various crops, little was found that addressed water table management effects on biomass production. Wareing (1978) reported that leaf shape may be profoundly modified by environmental factors. Dry weight of the plant was used to measure the amount of organic material synthesized by the plant. The ability of a plant to synthesize new material is dependent upon its leaf area. The rate at which new material is assimilated increases proportionately with the rate at which a plant grows and increases leaf area. Elk, et al. 38 (1966) reported that any factor affecting the size of corn plants should affect the leaf area as well. The actual yield obtained from a crop depends on the effects various factors have on the crop throughout the growing season. The water use of the corn crop varies with the stage of development (Sprague, 1977). Water loss early in the growing season is primarily from evaporation from the bare soil. As crop cover increases with leaf development, transpiration becomes an increasingly dominant factor. Sprague (1977) also reported that the stand height may affect the amount of water use by the plant. Low stands use low amounts of water. As the stand increases, water use increases rapidly, but with time the growing stand decreases its water use which is due to a peak and subsequent decrease in solar energy utilization in evapotransporation from the stand. Ritter and Beer (1969) reported that flooding corn early in the season was more detrimental to grain yield than flooding late in the season. Iel and Taylor (1969) reported that intermittent flooding early in thetgrowing season.reduced.corn yields compared to maintaining constant water tables of 0.15 to 0.30 m in depth. Damage to corn due to flooding or high water contents is probably caused by many factors including low oxygen or high carbon dioxide concentrations in the soil air, the plant’s respiration rate at flooding, reduced nutrient uptake, and possible toxicity of chemicals produced 39 reducing conditions. Alvino and Zerbi (1986) found that at the vegetative and flowering stage, plants reached their maximum height with shallowHwater'depths‘under both irrigated.and rain conditions. Highest yields were obtained on shallow water table depths even though grain moisture content increased as well. Baser, et al. (1981) reported that corn had maximum growth at water table depth of 0.3 m compared to 0.15 and 0.48 m. Rattan and George (1969) compared constant and varying' water table depths, at two‘ levels of nitrogen and two levels of the micronutrients zinc and copper. Corn grain yields were reduced at water table depths of 0.15 and 0.30 m, and varying water table depths with occasional flooding early in the growing season reduced yields even more. Higher levels of N, Zn, and Cu increased yields under well drained conditions and at shallow water table depths of 0.15 and 0.30 m. The uptake of N and Zn by corn was reduced by high water table depths and flooding. Follett, et al. (1974) found that corn shoot growth was at maximum with intermediate water table depths, and corn grain yields were lower at high and low water table depths compared to medium water table depths. Shoot growth decreased in high water tables due to poor aeration, and decreased in low water tables due to decreased water availability. SITE DESCRIPTION The Unionville site is located in.Tuscola County (S. 1/2 of N. 1/2 of S.W. 1/4 of Section 22, T.15 N. R.8 E). The Unionville research field is divided into three different treatment plots as shown in Figure 1. The 3.4 ha "subirrigation / controlled drainage" treatment (SI) and the 4.3 ha "conventional subsurface drainage" treatment (DO) .have subsurface 'tile drains spaced at 4.6 m at a depth of 0.8 m. The "no subsurface drainage" treatment (ND) is 5.4 ha in size. Each plot has a shallow surface drain providing good surface drainage. A dike was built at the perimeter of each plot. The site has three soil types that are identified on Figure 1. They are: 1) Tappan loam, 2) Thomas muck, and 3) Essexville loamy sand. The results of a soil textural analysis performed at Michigan State University are presented in Table 1. The Tappan loam soil is a fine-loamy, mixed calcareous, mesic Typic Haplaquolls (Soil Survey, 1980). The Thomas muck soil is a fine-loamy, mixed calcareous, mesic Histic Humaquept (Soil Survey, 1980). The Tappan and Thomas soils are poorly or very poorly drained. Surface water drainage is very slow to ponded with slow to moderately slow permeability. The Essexville loamy sand soil is a sandy over loamy, mixed calcareous, mesic Typic Haplaquoll (Soil Survey, '1980). Essexville soils are poorly drained, with rapidly permeable in the upper part and moderately slowly permeable in the lower part. 40 41 N ESSEXVILLE LOAMY SAND 9 ND TMT I I; \DO TMT .9 SI TMT . I ~ r\ x I / x D" O \ O x ‘ I , \ - X X . . \ 6 § ........ ARM oX ‘\\ ETMMWWWWE] E! I] I TAPRAN LOAM [Z] I“ X g x5 0 o \. THOMAS Mucx ‘\ R - SURFACE RUNOFF FLOW MONITORING AND COLLECTION I - ISCO suaSURFACE DRAINAGE SAMPLER x - SOIL AND SOIL VIATER SAMPLING LOCATION [Z] — SOIL AND SOIL WATER SAMPLING LOCATION ADDED 1991 o - OBSERVATION WELL LOCATION ------------------ - SURFACE FIELD DITCH Figure 1. Research Site Layout METHODOLOGY System Operation and Data Collegtion Water table, surface and subsurface tile outflow and rainfall were monitored using the bubbler system technique (Goebel, et al. 1985). A flow chart of the system used at the Unionville site is given in Appendix A. Water table depths and flow depths are measured using aIdatalogger that converts an analog signal from 7 pressure transducers which monitor pressure displacement caused by the depth of water in an observation well, flume well or orifice meter well. The automated bubbler system was installed October 29, 1989. Actual monitoring of tile drain outflow, surface drainage and 42 Table 1. Soil texture and classification So a e Depth, m Sand Silt Clay 'rextu re Ap (SI Zone) 0.00-0.30 67 25 8 Sandy loam Ap (DO Zone) 0.00-0.30 69 22 9 Sandy Loam Ap (ND Zone) 0.00-0.30 79 14 7 Loamy Sand 89 (SI,DO,ND) 0.30-0.51. 45 34 21 Loam Bw (SI,DO,ND) 0.51-0.81 45 32 23 Loam water table depth began on May 24, 1990. Frequent electrical and phone problems effecting data collection were solved in early June, 1990. For the 1991 growing season monitoring began on May 1, 1991 and the system ran virtually continuous without any major problems through out the growing season. In-line orifice meters (Protaswiewicz, et al., 1987) were designed, built and calibrated prior to their installation in the summer of 1989. The equation used to model flow through an in-line orifice meter under full pipe flow is taken from Sterns (1951) and has the form: W-2.086-I= (d2)2*K* (ptH)1/2 (1) where: W = flow rate, l/min df= Diameter of orifice, cm K = Orifice Discharge Coefficient (dimensionless) p: density of fluid, g/cm3 The SI and DO treatment areas each have a separate main from ‘which outflow' is :monitored. and. water samples collected. iLocation of water samplers both for surface and tile drains, soil and soil water sampling locations, and observation well 43 locations are shown in Figure 1. .At the beginning of the 1990 growing season, grab samples of the tile water were collected from the SI and DO treatment headstands until the bubbler system was fully functional in June, 1990, after which all samples were taken based on cumulative flow volumes using Isco Model 1600 automatic water samplers. Meteorglggical Data An on site LiCor 1200 weather station monitors daily average temperature, daily minimum and maximum air temperatures, daily soil temperature, daily rainfall, and daily net solar radiation. Data is downloaded from the data logger to a Radio Shack PC-100 on a monthly basis. Rainfall was also monitored in each of the three treatments using the bubbler system. Water Table Elevation Data The SI and DO treatments each have 6 water table observation wells installed as shown in Figure 1. The 6 wells are in two sets of three as follows: a well is 1 m from a tile drain lateral, another is located midway between two tile drain laterals (2.3 m), and the third is located in between the first two wells (1.6 m). The ND treatment has 6 observation wells through out the treatment plot as shown in Figure 1. All wells are placed to a depth of 1.5m, approximately 0.7m below tile depth. The observation wells are made of 2.54 cm diameter galvanized steel pipe. 44 Drainage Flow Monitoring and Water Sample Collection The Orifice meters measure flow rates which are used.to obtain proportional flow based tile water samples. The bubbler system monitors the depth of water by measuring the water pressure from the piezometer tubes of the orifice meter. The software calculates and accumulates the flow using equation (1). The Isco samplers are linked to the datalogger and computer that monitor orifice flow measurements. The software signals the datalogger to activate the Isco samplers every 19000 1 of accumulated flow. From August 8, 1990, through the remainder of the 1990 growing season, the control software‘was changed to take a tile drain sample every 57000 1 of flow because of frequent heavy rains. The water samples are stored in bottles within a insulated container of the Isco sampler. The Isco samplers are stored in an insulated box. water samples were usually retrieved twice a week, and occasionally just once a week. The samples were transported in an ice chest and frozen when brought to the Michigan State University campus. During June of 1991 it was noticed that bubbler lines used to monitor both orifice meters had been damaged by spring field work. This resulted in erroneous measurements of flow. A similar problem occurred for a few days in July when a backhoe crimped some of the orifice meter bubbler lines. Before repairing the lines in both cases, calibrations were made on 45 the damaged lines and the erroneous flow data was corrected. Two flumes were installed at the outlet of the surface drains of each treatment. Location of the flumes are indicated in Figure 1. The flumes were each calibrated in a laboratory at Michigan State University to obtain an exponential correlation of depth and.volume of flOW'Of water through the flume (Pruden and Fogiel, 1990). For both growing seasons, the non-linear regressions among the six flumes were almost the same and all yielded R2 greater than or equal to 0.99. The equation used to calculate flow rate through the flumes for both the 1990 and 1991 growing season has the form: Y'(O.OO9*(x2'°35)+0.8)*0.003785 ‘ (2) where: x Y Depth of Flow, mm Flow Rate, nP/min In the field, depth of flow was monitored using the bubbler system. Field calibrations of depth of flow for each flume was conducted at least once:a:month.during the growing season. During the 1990 growing -season, samples of the surface drainage water were collected using Coshocton wheels. The wheels were calibrated at Michigan State University. The wheels collected approximately 2% of the total surface outflow, and the composite sample was stored in a galvanized steel tank which was placed in an excavated pit. 46 Many problems occurred with the Coshocton wheels and galvanized steel tanks due to the heavy rains of August and September of 1990. The pit in which the tanks were placed often flooded and caused displacement of the tanks and/or collapse of the pit. Sediment build up in the Coshocton wheel frequently clogged the line running to the storage tank. The sample collector completely failed for one of the flumes in the SI treatment, so that flume was raised in order to force all surface outflow through the other flume. Heavy rains on September 6 and 7, 1990, washed out the flumes from the SI and ND treatment surface drainage collection sites, and no data was collected for this event from all three treatments. In August, 1990, a bubbler line for a flume in the ND treatment failed. In September, 1990, a bubbler line for a flume in the. DO treatment. failed. In October 1990, heavy rains made it impossible to keep the flumes in place for all three treatments, and.the surface outflow'data was too incomplete to be reported for that month. However, grab samples were Obtained from glass jar containers that were set in the surface ditch for all three treatments. All surface outflow reported from the ND treatment in August and September was estimated by calculating the outflow measured through the second operational flume and doubling the value. For the 1991 growing season, an air pressure activated.pumping 47 system was built and installed for sampling water directly from the surface outflow of each treatment. The bubbler system in place at the site was modified to turn on the surface outflow pumps by sending 10 psi of pressure through an air line after 77 L of flow were measured through the flumes. A composite sample was collected and stored in the same galvanized tanks. Continuous flume data and samples were collected during 1991. For both growing seasons, samples in the tanks were retrieved and put into frozen storage at the Michigan State University campus within 24 hours of the rain event. Soll and Soil Water Collection Soil samples during 1990 and 1991 were collected monthly except in May (after fertilizer application) and June when they were collected twice a month. The samples were collected using a hand bucket auger. Samples were obtained to 0.9m depth at 0.3m intervals. Each treatment was split into two replications (Figure 1) for the 1990 growing season. Within each replication, fiVe different samples from the same depth were composite into one sample. For the 1991 growing season, two more replications were added to each treatment (Figure 1) from which a composited sample was taken from each depth. Care was taken to not allow top soil to fall within the sample hole in order to prevent contamination of underlying sample depths. An approximately equal portion (about two handfuls) 48 from each depth was collected for composite samples. The holes were backfilled after sampling. Soil samples were stored in an ice chest during the time of sampling. The samples were immediately frozen if analysis was not going to be performed within 24 hours of collection. Suction lysimeters were installed for 1990 and 1991 to collect soil water samples. Lysimeters were installed at the soil sampling locations (Figure 1), and soil water samples were obtained to 0.9m depth at 0.3m intervals. Soil water samples were taken during soil sampling. The lysimeters were pumped of any standing water, 70 psi of vacuum was applied, and the soil water sample was pumped from the lysimeter within 24 hours. In order for proper extraction of water from the soil, there must be aIgood interface established between the suction lysimeter porous ceramic cup and the soil. In 1990, the lysimeters were not properly installed in accordance with the soil environment and very few samples were collected. In 1991, the lack of significant rainfall events early in the growing season caused severe soil cracking around the lysimeters and prevented the development of a good interface between the lysimeter and soil. The soil water samples collected in 1990 and 1991 did.not provide enough data to make comparisons from which to draw conclusions from among the three treatments. 49 Rain water samples were collected by attaching a funnel to a glass jar and mounting the jar onto a post. Samples were retrieved within 24 hours of the rain event, transported in an ice chest, and frozen immediately upon return to the Michigan State University campus. Grab samples of irrigation water were obtained from the SI treatment irrigation supply pipe and transported and stored the same way the rain samples were. All soil and water samples were analyzed for nitrate nitrogen, orthophosphate phosphorus, and potassium for the 1990 and 1991 growing seasons. Ammonia nitrogen analysis was performed on soil and water samples collected during the 1991 growing season. Analysis was performed at the Michigan State University Soil Test Laboratory using methods approved by the United States Environmental Protection Agency (EPA). Nitrate nitrogen analysis for both soil and water samples was performed using EPA method 353.2 (1989). Ammonia nitrogen analysis for both soil and water samples was performed using the Salicylate method. Phosphorus concentrations from soil extracts were obtained by Method 24-5.1 described by Summers (1986). The flow injection method.described.by Murphy, et al. (1986) was used to obtain phosphorus concentrations from water samples. Potassium concentrations were obtained by the auto— analyzer method/ exchangeable potassium procedure for both soil extract ‘ samples and water samples approved by the United States Environmental Protection Agency (1989). 50 All water sample nutrient content results were expressed in mg/l (ppm). Loadings for both subsurface drain and surface drain samples were calculated by determining the total cumulated flow that occurred over the period between the taking of two water samples that were analyzed for nutrients. The concentration of the nutrients found in the water sample were multiplied by the cumulative flow from the unit area of the treatment. The soil nitrate nitrogen. and ammonia nitrogen analysis results were expressed in concentrations, and the orthophosphate phosphorus and potassium results were expressed in loadings per acre furrow slice. The furrow slice was assumed to be approximately 16.9 cm. The soil samples collected in the field are obtained from a 30.48 cm slice, so the results were adjusted to the actual sampling slice. Alachlor analysis in soil samples were performed at the Michigan State University Pesticide Research Lab. Analysis on water samples were conducted at Heidelberg College in Tiffin, Ohio using pesticide immunoassay screens. These screens confirm the absence of pesticides above the method detection limit. If pesticides are detected, follow up analysis is performed to determine specific alachlor concentrations within a 0.2 ug/l (ppb) detection limit. Both alachlor methods are approved by the Environmental Protection Agency (1989). 51 o o ' Da a Plant leaf area and stem volume measurements were conduCted.at different plant growth stages on selected plants from each treatment for both growing seasons. Two plant growth stages were measured in 1990, and three were measured in 1991. For both.growing seasons, the SI and DO treatments were split into north and south replications and had 35 randomly selected plants monitored in each replication. In 1990, the ND was split in east and west replications and had 35 randomly selected plants monitored in each replication. In 1991, the ND was split into north and south replications. The stem volume was determined by measuring the minimum and maximum diameter of the base of the corn stalk using a caliper, and recording the height of the last unfurled corn leaf collar. The formula for the stem volume is as follows: StemVol.- [ (Stemn+Stemx) /2012*3 .14/4*Stemh (3) where: Stem Vol. = Computed Stem Volume, cm3 Stemn = Minimum Stem Diameter, mm Stemx = Maximum Stem Diameter, mm Stemh = Height of stem, cm Stem volume was converted to above ground plant biomass for the respective 1990 and 1991 growing seasons by the equations: y--1.41+0.18*x (4) y-287.24+0.07*x (5) where: x = Stalk Volume, cm3/m2 y = Above ground plant biomass, g/m3 The linear regression graphs and analysis from which equations (I) and (5) index was C treatment by Nutrient ana from each tr two samples analyzed for corn were r treatment a analysis. rePlication 5359185 for 11' July 25, Plants pick two satples 52 (4) and (5) were computed are presented in Appendix H. Leaf index was computed by dividing the total leaf area of a treatment by the area of the treatment with unitSIRF/mz. Nutrient analysis was performed on plants randomly selected from.each treatment. In 1990, ten plants were composited into two samples from each treatment on July 25 and August 8, and analyzed for nutrient content. On August 8, 1990, 10 ears of corn were randomly picked from each replication within each treatment and composited into a sample for nutrient content analysis. In 1991, ten plants were picked from each replication within each treatment and composited into two samples for analysis. Plant samples were collected on July 11, July 25, and September 4, 1991. The ears of corn from the plants picked on September 4, 1991, were also composited into two samples from each replication and analyzed for nutrient content. Plant and kernel nutrient analysis were performed at the Michigan State University Soil Test Laboratory using Environmental Protection Agency (1989) approved methods. The analysis results were expressed in terms of percent nitrogen, phosphorus and potassium. The actual amount is calculated by multiplying that percentage by the mass of sample collected. For the 1990 and 1991 growing seasons, Pioneer 375L variety corn was planted at 69,300 seeds/ha. Planting was performed 0n Ha}, 8I and herb fertiliz seasons. growing Table : ~ .713 km LI: ”TIL”: 53 on May 8, 1990, and on May 21, 1991, respectively. Fertilizer and herbicides application rates and dates for both growing seasons are presented in Table 2. The yield goal for fertilizer application was 2.7 metric tons/ha for both.growing seasons. The fertilizers were broadcasted preemergence both growing seasons. Table 2. Fertilizer and herbicide summary 112; Rate . 1990 Growing Season: 1991 Growing Season: Fertilizer, kg/ha: Date Applied 5/8/90 5/21/ 91 Total Nitrogen 214 198 Total Phosphorus 101 77 . Total Potassium 168 118 Herbicides, L/ha: Date Applied 6/1/90 6/7/9 1 Banvel 0.24 0.38 2-40 Amine 0.24 0.38 Lasso 0.38 The field operations, irrigation and drainage control schedule for the 1990 growing season is presented in Table 3, and for the 1991 growing season in Table 4. Statistlcal Analysis Regression analysis was performed after all observation points were calibrated in the field. The bubbler system pressure transducers have a linear response to change in pressure. Each pressure transducer was frequently calibrated to ensure it was _ operating within specifications. After all calibrations and regressions were performed, the correlation mm 3. F14 schedule 19‘. x (15 ls- u; H “T ‘ \. .. \ \_. _m m w (n U, “’ \L) \O C) (J (J O 54 Table 3. Field operations, irrigation and drainage control schedule 1990 REES Field Operation 4/30/90 - 5/1/90 Plowed using disk barrow 5/8/90 Planted Corn 5/8/90 Broadcasted Fertilizers, Preemergence 6/1/90 Sprayed Herbicides 6/3/90 5 6/18/90 Cultivated 7/1/90 SI put in controlled drain mode 7/3/90 SI irrigation started 7/8/90 SI irrigation suspended 7/18/90 SI put in drain mode 7/28/90 SI put in controlled drain ' mode 8/1/90 SI irrigation started 8/3/90 SI irrigation suspended 8/4/90 SI put in drain mode 8/8/90 SI put in controlled drain mode 8/26/90 SI put in drain mode 9/4/90 SI put in controlled drain mode 9/6/90 SI put in drain mode 9/12/90 SI put in controlled drain mode . 9/12/90 SI irrigation started 9/14/90 SI irrigation suspended 9/14/90 SI put in drain mode for remainder of season and winter 11/8/90 SI and DO harvested 12/23/90 ND harvested coefficient was determined and this was used as a guide as to whether observations were being made accurately. The soil sample nutrient loadings were run through a standard two-sample t test for significant difference between each treatment. The formula given by Harnett (1970) takes the form: t-—P—x- 6 s/n0.5 ( ’ m1. 4. Field 0? schedule 1991 where: si 55 Table 4. Field operations, irrigation and drainage control schedule 1991 { pate Field Operation .5/12/91 Plowed using disk harrow 5/21/91 Planted Corn and Fertilized 5/27/91 SI put in controlled drain mode 5/7 / 91 Sprayed Herbicides, Preemergence 7/10/91 SI irrigation started 7/11/91 SI irrigation suspended 7/18/91 ' SI irrigation started 7/21/91 SI irrigation suspended 7/24/91 SI irrigation started 7/28/91 SI irrigation suspended 8/7/91 SI put in drain mode 8/10/91 SI put in controlled drain mode 8/17 [91 SI put in drain mode 8/19/91 SI put in controlled drain mode 9/3/91 SI put in drain mode for season and winter 10/8/91 SI, DO and ND harvested where: t = two-sample t-test value x = mean difference between sample sets u - population mean difference of null hypothesis (yo = 111-p2 = 0) S = standard deviation of sample difference n = number of sample differences tested The null hypothesis states that between each of the 3 treatments, the difference between the sample averages is zero. The t-test value computed for all sample sets were tested at a significance level of 0.05. If the t value exceeds the critical value for the test run, the null hypothesis is rejected which means that there is high Variation among samples analyzed between treatments. This test must be run before conclusions can be made when comparing res‘uts between treatments. The leaf index and plant biomass results were tested for significant d block design. seasons were The test for from the thr observed leaf for a random: of variance t (1985). A te the treatment :t2= : t p 5”" Signifi signifiCanCe performed USj (1966) 56 significant difference between treatments using a randomized block design. The leaf index measurements for both growing seasons were plotted versus time and are shown in Appendix G. The test for significant difference between the leaf indexes from the three treatments were performed on the maximum observed leaf index for both growing seasOns. The data table for a randomized block design and the format for the analysis of variance table follows the procedure described by Peterson (1985). A test of the significance of the differences among the treatment means is performed by FT on the hypothesis Ho:t1 = t2 = = tp = 0 against Hazt1 75 t2 73 :6 tp ¢ 0. If the test shows significance (i.e. rejects H5), then a further test Of significance against which pairwise comparisons are judged was performed using Fisher’s Protected LSD as described by Fisher (1966). the pressure trar signal to Change The regressions digitally conve: presented in A coefficient squa zone 5, lead, we: equations obseri occurred due to corpcnents durin- occurred due to lines in 1991. I during both groh. lines were routiI 1990 and 1991. “:an but Still rede for those p RESULTS AND DISCUSSION System Operation Data The pressure transducers used.have a linear response in analog signal to changes in pressure caused by variations in depth. The regressions used in 1990 to obtain depths from the digitally converted signal, and the same for 1991 are presented in Appendix A. The lowest R2 (correlation coefficient squared) was 0.817 for OWAHdS (Qbservation Well, zone A, Head, well#§) in 1991. The differences in regression equations observed from 1990 compared to 1991 may' have occurred due to the renovation of the system electronic components during the winter of 1990 and 1991. Changes also occurred due to the replacement of many of the microtubing lines in 1991. Water that got into some of the bubbler lines during both growing seasons affected the calibrations. The lines were routinely blown out using high air pressure during 1990 and 1991. There were periods when microtubing was damaged but still functional, and regression measurements were made for those periods. Slight changes in regression values from month to month in 1991 did occur, but not enough to warrant concern. The regression equations Appendix A show inconsistencies in the slope values of different observation points that were :read by the same pressure transducers. Much of this effect was attributed to damaged but useful air lines. Air lines 57 that were 1201 inconsistent transducer a inccnsistenc slope values The effect 1 in 1991. Ne :onitoring I ctservat i on ‘- ‘:" l .cs E l AF. ' eh] I -f\~\ 04h \ 58 that were monitored by the same pressure transducer but showed inconsistent slope values were booked to a different pressure transducer and calibrated. This test did not remove the inconsistencies in the slope values and the effect on the slope values was determined to be dependent on the air lines. The effect is more prevalent for the 1990 growing season than in 1991. New lines were installedfor the flume and orifice monitoring wells in all treatments, but not for all the observation wells. nxdrqlegx 600 ES EVENT — CUMMULATIVE 500 — 400 -* 300 - 200 - 100q LALLLLEL I I I I I I I T I I I V I I MAY JUN JUL AUG 'SEP OCT NOV _ MAY JUN JUL AUG SEP OCT NOV 1990 1991 Figure 2. Site rainfall Tneaccunulated r 1990 through Oct: Cctd‘: r 6, 1991 i: the LiCor weather 3. Accumulated r a, and 170 rm fc rainfall amounts cozpared with the for both growing the 1990 growing 5 Ir average rainfa accuzulated ra inf Average daily wa t SEESCRS are Show? :a‘:‘ ‘e depths Pres " ‘Ii . IEAAS In each tre 20 mi , I‘t‘i’eridix B. The I" I ripen“)! B as I. e d manna 1 1y fish; “h °f 0.4 to 552$ 1 ens Subir I. has 1 59 The accumulated rainfall and daily event rainfall from May 1, 1990 through October 31, 1990, and from May 1, 1991 through October 6, 1991 is plotted in FigureIZ. The data collected by the LiCor weather station datalogger is presented in Appendix C. Accumulated rainfall for the 1990 growing season was 578 mm, and 170 mm for the 1991 growing season. The accumulated rainfall amounts of the 1990 and 1991 growing seasons were compared with the regional 30-yr average accumulated rainfall for both growing season periods as shown in Figure 3. During the 1990 growing season, accumulated rainfall exceeded.the 30- yr average rainfall by 32%. During the 1991 growing season, accumulated rainfall was 52% below the 30-yr average. Average daily water table depths for the 1990 and 1991 growing seasons are shown in Figures 5 and 6, respectively; The water table depths presented are the daily average of 6 observation wells in each treatment plots 'The well depths, recorded every 20 minutes for each functional observation well, are shown in Appendix B. The elevation of the well top are reported in Appendix B as well. For the 1990 and 1991 growing seasons, the SI headstand was opened after substantial rainfalls and closed manually after the water table reached the desired depth of 0.4 to 0.6 m below ground surface. For both growing seasons, subirrigation was performed the months of July, August and September. 0 . 1-4.4. e A v P.» ..,~ f.» A. ‘ .J a. r. h r. 5 4. 2 2...! SE SI, RIJ. in A x 4 e u A... 2 4. Fe 3. r.» 7‘ 4, 5 n. v A u o t t F. .L . D). . .t Gust}... I..." 5.: i .3333). . e, EM flflfll 60 700 . 600 500 A 400 , 300 200 100 578 Figure 3. 80.0 - 60.0- 40.0 - zeo- oe J‘L 0.0 H mm Rain 0.2- 0.4- 0.6‘ 0.8- 1.0- 1.2— 1.4-I Watertable Elevation Below Surface. In 1.6 6/91 1 C3 05/01/90—10/31/90 05/01/91-10/ IlmmwmuiaxnnMnnmI Comparison of site rainfall to seasonal average L I‘lllu IrL -i I] l LIL gflJLln Sublrrlgotlon \ --- Drainage Only ---- No Drainage \“~.. 1.8 l I T l l June July August September October November 1 990 Watertable Depths 1990 mus Ru 1» t: f .1 Wenonah“ (Imflm lick-w Godot... m D _1 “We 5. Ha During the 1 Occurred at 5mm in Fll Opened and C :0 0-6 III ShirTigatio rfintaining Frcved to l: drainage moc September 14 the ground hmisting feI ‘1 dul”in? mm of t tree» wants w t.‘ . 0mm“? of 61 50.0— .5 40.0-4 E 30.0-1 E 20.0-4 ‘°'° 1 1 1 II 0.0 11. 1.1I l - 1' A! In 1-111LI j 0.0- Subirrigation 0.2- --- Drainage Only 0.4— ——-- No Drainage or- )3 _ '. Hi I'K 0'6 \‘ I\ ' A If"- \r 1.0“ ‘ ’ 1.2-1 . \f.~\\r‘_‘.’ll ‘4'." s ‘.‘-‘ '. a A fi .0 a. . .I 0" ‘0‘ b~o v. Mitobh Elevation Bolow Surface. m { 1.6— 1.8 I I l I T I May June July August September October November 1991 Figure 5. Watertable Depths 1991 During the 1990 growing season, frequent high events rainfall occurred at the end of July, August, September and October as shown in Figure 2. The headstand in the SI treatment was opened and closed to maintain the water table at or near 0.4 to 0.6 m during the period of drainage control and subirrigation. But due to the 1990 high event rains, maintaining the desired water table depth in the SI treatment proved to be difficult. The SI treatment was put into drainage mode for the remainder of the growing season on September 14, 1990 lowering the water table from 0.6 m below the ground surface to tile drain depth (0.8 m) so that harvesting could be performed. The low rainfall amounts that fell during the 1991 growing season allowed more constant control of the water table in the SI zone. The DO and ND treatments were very dry to the impermeable layer by the beginning of August through the end of the 1991 growing season . c“ :1 ‘C4 E 8.- ‘—n . r"- .W _ a Figure 5, I The monthly "0111395 fr: acouzulated treatlaent f. in Table 5. 01:1le for i Q 890 total 62 — Subirrigation --- Drainage Only 16% ---- No Drainage ," 14— 12— 10— O T I I l I I I I "I I I I 'I MAY JUN JUL AUG SEP OCT NOV MAY JUN JUL AUG SEP OCT NOV 1990 1991 Figure 6. Total Drainage Volumes The monthly accumulated tile and surface drainage discharge volumes from the SI and DO treatments, and the monthly accumulated surface drainage discharge volume from the ND treatment for the 1990 and 1991 growing seasons are presented in Table 5. The total accumulated tile and surface drainage outflow for both growing seasons are shown in Figure 6. The 1990 total drainage outflow from the SI treatment was 17.57 mm, 16.11 mm from the DO treatment, and 13.18 mm from the ND treatment. The 1991 total drainage discharge from the SI treatment was 3.74 mm, 2.00 mm fromIthe DO treatment, and 0.66 mm from the ND treatment. The 1991 growing season had 71% less rain than during the 1990 growing season, which is why the drainage V0 substantially 18$ subirrigation in< cezpared to a wat Schwab and Fouss :1983), Jacobs ar Sagas, et al. (1 increased total d. drainage cozparej Iable s. Monthlj kit“ Ra . lfibu I?" is stile 4 ~ Jun] 7 ‘ karat 1 6; Say: i_ ' 0c: .f“ ~\ .4 ‘ “Kai: F . c 1991 May .. ; June f: JLly A: A“92st ‘ ~ 56;: 55 0c: 22 m1: fit (Cast 1991 = onév 63 the drainage volumes for the 1991 growing season were substantially less. campbell, et al. (1985) reported that subirrigation increased total drainage to edge of field compared to a water furrow system. Willard, et al. (1927), Schwab and Fouss (1967), Schwab, et a1. (1980), Schwab et. al (1983), Jacobs and Gilliam (1985), Bottcher, et al. (1981), Skaggs, et al. (1982), and Evans and Skaggs (1989) reported increased total drainage to edge of field due from subsurface drainage compared to fields with no subsurface drainage. Table 5. Monthly drainage discharge volumes SI DO ND Rain Tile Surface Tile Surface Surface flwmh mm mm mm tML. 1990 May 35 - 0.30 - 0.25 1.28 June 47 1.13 0.49 0.61 0.28 1.15 July 76 3.65 0.48 0.84 0.79 0.12 August 169 1.84 2.64 2.50 1.54 8.91 Sept 124 4.35 1.05 4.50 2.02 1.72 Qgt 121 1.65 - 2.77 - - Totals 578 12.62 4.95 11.22 4.89 13.18 1991 May 26 1.11 0.20 1.16 0.17 0.29 June 13 0.00 0.00 0.05 0.00 0.00 July 16 0.10 0.11 0.10 0.02 0.02 August 55 0 53 0.34 0.09 0.22 0.26 Sept 22 1 11 0.00 0.07 0.00 0.00 Oct _§§ 0 16 0.08 0.04 0.08 0.09 Total= 170 3.01 0.73 1.51 0.49 0.66 (Oct 1991 = Oct 1 - Oct 6, 1991) The 1990 and 1991 growing season accumulated tile drainage from the SI and D0 treatments are shown in Figure 7. The 1990 SI accumulated tile drainage outflow was 12.62 mm, and 11.22 mm from the DO treatment. The tile discharge from the SI treatment was 11% higher due to the irrigation of the SI —) Q ,.. V' I --- "u a i \ E E-n \ ‘d i F 7— H!“ v .‘ “We 7. T' .V'A utatment. 64 — SI Tileflow --- DO ‘l‘Ileflow O I I I I I I I I I I I I I MAY JUN JUL AUG SEP OCT NOV MAY JUN JUL AUG SEP OCT NOV 1990 1991 Figure 7. Tile Drainage Volumes treatment. In addition, when irrigation of the SI treatment began on July 3, 1990, the control valve in the headstand was not properly set. It was not discovered and fixed until July 5, 1990. The SI tile drainage volume for July, 1990, was 3.65 mm, while the D0 tile drainage volume was only 0.48 mm. The 1991 growing season accumulated tile drainage from the SI and D0 treatments are shown in Figure 8. The SI had 3.01 mm of accumulated tile discharge, and the D0 treatment had 1.51 mm, As in 1990, the 50% increase in tile drainage from.the SI treatment was due to irrigation. Septe:ber of accumulated treatments. treatment w- Although the the highest under contr stcrage cape of the growi- scil. By 39 for the ten: the SI and contlnual re outflows. The highest 4? ' “Image VC ”the Spring drainage 0U a 0i tile draj did hot 8m Hgnthl three t] 65 September of the 1990 growing season had the highest monthly accumulated tile drainage discharge for both the SI and DO treatments. The September tile drainage outflow from the SI treatment was 4.35 mm, and 4.50 mm from the D0 treatment. Although the 169 mm of rain that fell during August, 1990, was the highest of the growing season, the SI treatment was still under controlled drainage, and the D0 treatment still had storage capacity for water in the soil profileu At this point of the growing season, corn is still removing water from the soil. By September, the SI treatment was put in drainage mode for the remainder of the year, and the soil profiles of both the SI and D0 treatments were near saturation from the continual rainfall thus resulting in the high tile drainage outflows. The highest 1991 growing season monthly accumulated tile drainage volume occurred in May for both the SI and D0 treatments. The tile drainage outfl w measured resulted from the spring thaw. The SI treatment had 1.11 mm of tile drainage outflow in May, and in September, 1991, when the treatment was put in drain mode. 'The D0 treatment had 1.16 mm of tile drainage outflow in May, after which drainage volumes did not exceed 0.10 mm for the remainder of the growing season . Monthly accumulated surface drainage discharge volumes from all three treatments for both growing seasons are shown in Tables. The 199: discharge from tzl DOtreatnent, an. DCtreatnents hazl the 1990 growinl drainage outf 10;] high water table: | n- of rainfall ; drainage out f l 0;. The 1990 and 199 outflow for all 51 treatment out 62% lower than t drains in the NI: from the high rel surface ditch. Capability of th in high surfac Se 1 h Mb”. 1990 i l1967)p SChwab' and Gilliam (191 66 Table 5. The 1990 growing season accumulated surface drainage discharge from the SI treatment was 4.95 mm, 4.89 mm from the DO treatment, and 13.18 mm from the ND treatment. The SI and DO treatments had similar surface drainage volumes through out the 1990 growing season. The highest SI monthly surface drainage outflow of 2.64 mm occurred in August, 1990. The high water tables maintained by drainage control and the 169 mm of rainfall in August, 1990, contributed to high surface drainage outflow from the SI treatment. The 1990 and 1991 growing season accumulated surface drainage outflow for all three treatments are shown in Figure 8. The SI treatment outflow was 1% higher than the D0 treatment, and 62% lower than the ND treatment. Because there are no tile drains in the ND treatment, the soil profile became saturated from the high rain events, and excess water drained via the surface ditch. The rain intensity exceeded the infiltration capability of the soils in the SI and D0 treatments resulting in high surface drainage outflow from mid-July through September, 1990. Willard, et al. (1927), Schwab and Fouss (1967), Schwab, et al. (1980), Schwab et. a1 (1983), Jacobs and Gilliam (1985), Bottcher, et al. (1981), Skaggs, et a1. (1982), and Evans and Skaggs (1989) reported decreased accumulated surface drainage to edge of field due from subsurface drained fields compared to fields with no subsurface drainage. Campbell, et al. (1985) reported that subirrigation decreased surface drainage to edge of field cozpa The I treat 1990. great the Skagt contr CCHVE The l 2.02 treat Subsl regu] 1990. drair 9r0uj 67 compared to a water furrow system. The 1991 growing season surface drainage volumes for all three treatments shown in Figure:8‘were substantially less than from 1990. The 1991 SI treatment surface drainage outflow was 29% greater than from the D0 treatment, and 10% higher than from the ND ‘treatmentw ‘The soil, profile of the D0 and. ND treatments was near dry from July through the end of the 1991 growing season. Most rainfall water infiltrated and remained in the soil of all three treatments and was used by the corn instead of draining via the surface ditches. Gilliam and Skaggs (1986), and Deal, et al. (1986) reported that controlled drainage increased surface runoff compared to conventional subsurface drainage. Evans and Skaggs (1989) stress that the design and management of controlled drainage systems directly affect the amount of surface drainage to edge of field. The D0 treatment had the highest surface drainage outflow of 2.02 mm in September, 1990. The soil profile in the D0 treatment could not store and sufficiently drain the subsurface water after the heavy rains of August, 1990, which resulted in increased surface drainage outflow in September, 1990. The ND treatment had substantially higher surface drainage volumes than the tile drained treatments for the 1990 growing season. The 195 all th: amount: dis-aha: treat: little treatml "IIT‘ 4' ‘l {I Figure 68 The 1991 growing season monthly surface drainage volumes from all three treatments were very low due to the low rainfall amounts. The 1991 growing season accumulated surface drainage discharge from the SI was 0.73 mm, 0.49 mm from the D0 treatment, and 0.66 mm from the ND treatment. There was little difference in surface drainage volumes among the three treatments, except for the SI treatment in July and August, 1991. Raising the water table may have increased the surface outflow from the SI treatment during July and August. This was also noted in August of 1990. 14 -— Subirrigation --- Drainage Only ---- No Drainage ./ 12- / 10- [I 8— I E I! 5 " .' 4n 2 -1 O I I I I I I I I I F-—'I I I MAY JUN JUL AUG SEP OCT NOV MAY JUN JUL AUG SEP OCT NOV 1990 1991 Figure 8. Surface Drainage Volumes Eat: F. .52! 69 Nutrient Table 6. Rainfall nutrient loadings and concentrations Date N03-N NH,-N 90,-? X 2359 ppm Lg/ha ppm kq/ha ppm kq/ha ppm ka/hg 06/12/90 6.07 1.21 0.19 0.04 1.10 0.22 06/25/90 4.13 11.15 0.13 0.35 1.70 4.59 07/17/90 1.06 2.65 0.21 0.53 3.20 8.00 07/19/90 0.61 2.14 0.10 0.35 3.20 11.20 08/02/90 0.00 0.00 0.27 0.16 1.60 0.96 08/06/90 0.55 4.46 0.35 2.84 1.19 9.64 08/14/90 1.91 0.57 2.08 0.62 8.25 2.48 08/20/91 0.67 2.35 0.31 1.10 1.69 5.92 08/28/90 0.66 3.30 0.22 1.10 0.56 2.80 09/17/90 0.03 0.07 0.22 0.51 0.56 1.29 09/19/90 1.15 0.92 1.92 1.54 2.75 2.20 10/02/90 1.89 0.76 0.37 0.15 0.50 0.20 10/04/90 0.47 1.41 0.23 0.69 2.13 6.39 10/11/90 0.73 5.26 0.23 1.66 2.63 18.94 07/29/91 1.75 0.18 1.13 0.11 0.27 0.03 2.63 0.26 08/16/91 1.21 1.21 1.21 1.21 0.20 0.20 0.98 0.98 08/19/91 0.30 0.45 0.30 0.45 0.13 0.20 0.50 0.75 Nutrient concentrations and loadings of rain samples are presented in‘Table 6. lRain samples were not collected for all events for both the 1990 and 1991 growing seasons. The rain samples that were collected contained relatively high concentrations and loadings of nitrate nitrogen, orthophosphate phosphorus, potassium, and ammonia nitrogen. The extremely high concentrations and loadings of nitrate in the June, rain samples may be nitrogen found 1990, explained by the fact that, for those events, the collector was only 0.5 m above the ground and may have been contaminated by the surrounding soil. There were no documented measurements of average regional rainfall nutrient concentrations and loadings found. There are early PC water Sal-"i? precipitati (Brady, 19 losses fro: from ani: operations. surface are chenical f potassium associated b‘jI-‘inds. of dried ar the area is Nutrient CC in Table .7 . r““AJ‘P‘itOred. orthOPhOSp} in all ir iRigation Containing 70 are many possible sources of the nutrients found in the rain water samples. Nitrate and ammonia nitrogen may be in precipitation as a result of atmospheric fixation of nitrogen (Brady, 1984). The nitrogen source would include gaseous losses from the soils of the regional agricultural lands, and from animal manure from surrounding dairy and swine operations. Orthophosphate phosphorus sources above the soil surface are primarily from crop residues, animal manures, and chemical fertilizers. The orthophosphate phosphorus and potassium found in the rain samples would most likely be associated with particulate matter carried into the atmosphere by winds. This would primarily be soil dust or fine particles of dried animal manure. The surface soil at the site and in the area is easily eroded by wind when unprotected. Nutrient concentrations of the irrigation water are presented in Table 7. Since the volume of irrigation water used was not monitored, loadings were not computed. The concentrations of orthophosphate phosphorus and potassium were relatively high in all irrigation samples tested. 1 The source of the irrigation water is a nearby agricultural drainage channel containing backwater from the Saginaw Bay of Lake Huron. The drainage waters that enter the channel probably carry substantial concentrations of nutrients. Average monthly nitrate nitrogen, orthophosphate phosphorus, and potassium concentrations in samples collected from the tile drain outflow of the SI treatment are presented in Table 13 7. I: ’31—'— Date 08/02/90 09/12/90 07/18/91 07/24/91 8. The c collected : presented concentrat saeples are drainage nitrogen, , Table 3 , F“‘-——__ 1709 APril Hay JUne JUIY AUgUSt Sept octOber 1991 May June July AUQUSt Sept October The Cencen a“Tiple Wer 55m 71 Table 7. Irrigation water nutrients Faun Date N03-N NHk-N 130,-? K 08/02/90 0.00 0.10 2.60 09/12/90 3.50 0.10 2.80 07/18/91 0.00 0.18 0.11 2.10 07/24/91 0.30 0.09 0.12 2.10 8 . The concentrations of the same nutrients in samples collected from the tile drain outflow of the DO treatment are presented in Table 9. All 1991 ammonia nitrogen concentrations and loadings found in tile and surface drainage samples are presented following the results and discussion of drainage water concentrations and loadings of nitrate nitrogen, orthophosphate phosphorus, and potassium. Table 8. SI tile drainage nutrient concentrations Nos-N: ppm P0.-P. ppm X. ppm Mgnth 3 AN HIGH Egg MEAN HIGH LQE MEAN HIGH £95 1989 '“' 7"“ ‘““‘ “" -- November 4 14.5 21.1 9.3 0.06 0.07 0.05 8.0 15.0 5.0 1990 April 2 8.5 8.7 8.2 0.09 0.09 0.08 14.7 14.7 14.7 May 6 11.3 15.5 9.4 0.08 0.10 0.05 14.1 22.6 8.4 June 5 13.4 17.0 10.4 0.03 0.07 0.00 8.4 10.0 4.4 July 15 1.5 9.3 0.0 0.09 0.13 0.07 3.7 8.9 2.1 August 21 7.5 17.2 0.8 0.26 0.36 0.01 12.8 31.6 3.2 Sept 17 19.2 31.3 6.4 0.23 0.27 0.18 16.2 39.5 2.3 October 11 32.6 38.4 17.9 0.21 0.23 0.16 18.3 45.7 13.3 1991 May 7 17.6 31.6 10.0 0.11 0.12 0.08 10.4 15.8 4.8 June 21 19.3 23.5 7.8 0.11 0.12 0.09 25.6 38.6 1.1 July 16 7.4 25.9 0.0 0.11 0.13 0.10 10.6 27.3 2.1 August 11 0.7 1.4 0.1 0.11 0.14 0.10 3.4 4.8 2.1 Sept 11 0.5 0.9 0.1 0.15 0.16 0.12 3.8 4.8 2.6 October 1 1.0 0.15 1.1 The concentrations of nitrate-nitrogen in tile drainage samples were higher from the D0 treatment than from the SI samples during both the 1990 and 1991 growing seasons. The “Q l\ U73- L. QmpF-‘F'L‘. 72 ' Table 9. D0 tile drainage nutrient concentrations Noa-N, ppm PO4-P, ppm X, ppm Month g MEAN HIGH LOW MEAN HIGH LOW MEAN HIGH ;_fl 1989 ‘ ‘November 4 17.6 23.0 12.7 0.06 0.06 0.05 8.8 18.0 5.0 1990 April 2. 24.3 24.9 23.6 0.09 0.10 0.07 6.1 6.3 5.8 May .» 6 18.0 22.0 15.9 0.09 0.10 0.07 4.5 5.3 3.7 June 5 17.2 22.2 15.9 0.05 0.19 0.00 5.8 8.9 4.7 July 14 27.2 64.8 7.9 0.10 0.17 0.00 4.7 8.4 2.6 August 18 42.7 60.5 0.1 0.30 1.02 0.00 6.1 7.1 4.1 Sept 18 52.8 77.5 21.4 0.22 0.25 0.07 7.2 8.9 3.9 October 9 65.1 81.3 52.4 0.22 0.25 0.20 6.4 7.4 6.2 1991 May~ 13 17.8 46.7 4.3 0.10 0.13 0.00 3.5 5.8 2.1 June 21 23.5 34.3 10.5 0.11 0.12 0.09 4.5 6.7 2.3 July 13 19.6 29.8 0.0 0.11 0.13 0.09 4.7 6.1 2.6 August 9 11.5 15.2 5.7 0.20 0.72 0.10 4.5 5.8 3.2 Sept 4 6.9 6.9 4.5 0.16 0.18 0.15 5.9 6.3 5.8 October 1 0.7 0.14 1.6 only exception occurred in the one sample collected from each treatment within the first 6 days of October, 1991. Grab samples Were taken from the headstand of the SI and D0 treatments.in November, 1989, and.the average nitrate nitrogen concentration of the SI treatment tile water samples was 14.5 ppm, and 17.6 ppm in the DO treatment samples. The concentrations found. in grab samples taken from the SI headstand decreased to 8.5 ppm in April, 1990. When samples were taken based on flow beginning in June, 1990, the average concentration in SI tile water samples increased slightly to 13.4 ppm nitrate nitrogen, but fell to 1.5 ppm in July, 1990. With the heavy rains of late July through.0ctober of 1990, the average concentrations in the tile drainage outflow increased to 32.6 ppm nitrate nitrogen in October due to the higher subsurface drainage flow. 73 The average concentrations of nitrate nitrogen found in grab samples taken from the DO treatment headstand in April, 1990, were 24.3 ppm. The average nitrate nitrogen concentrations decreased in May and June, 1990, and increased from July through October, 1990, due to the heavy rains which leached more nitrate nitrogen with the increased subsurface drainage outflow. In October, 1990, the highest DO treatment average nitrate nitrogen concentration of 65.1 ppm was observed. Through out the 1991 growing season, all samples taken from the SI and DO treatment headstands were flow based. The SI average monthly nitrate nitrogen concentration in May, 1991, was 17.6 ppm, and 17.8 ppm from the DO treatment tile drainage outflow. During June, 1991, the bubbler system was miscalculating flow' rates and. activating the tile. drain samplers when little to no tile flow occurred. These samples from both treatments observed an increase in nitrate nitrogen concentrations. The SI treatment tile drainage nitrate nitrogen concentrations decreased to 7.4 ppm in July, 1991, and decreased to less than or equal to 1 ppm nitrate nitrogen from August through October, 1991. The DO treatment observed a gradual decrease in nitrate nitrogen concentrations in tile drainage outflow from July through October, 1991. The July and August, 1991, DO average tile nitrate nitrogen concentrations remained above the 10 ppm drinking water standard, but fell below 1 ppm in one sample 74 taken in October, 1991. Because of the high solubility of nitrate nitrogen, holding the water in the SI treatment by controlling the subsurface drainage reduced the nitrate nitrogen concentrations leached to the tile drains compared to the DO treatment. The average monthly orthophosphate phosphorus concentrations from the SI and DO tile drainage outflow showed little difference for most months as shown in Tables 10 and 11. Orthophosphate phosphorus appeared in higher quantities in the tile drainage water during periods of higher tile outflow, indicating the propensity of orthophosphate phosphorus to move through the soil and be discharged from the drainage system during periods of excess soil water. The concentrations of orthophosphate phosphorus found in the tile drainage outflow from both treatments remained lower than concentrations found in the rain samples through most of both growing seasons. Phosphorus is generally low in the subsoils through which subsurface drainage water must pass, and thus are generally low in tile drain water (Campbell et al., 1985). Phosphorus is generally referred to as a soil bound nutrient, and usually is lost from surface drainage. As a soil bound nutrient, the source of orthophosphate phosphorus in the rain samples was probably in soil particulate matter and to a less degree animal manure particles carried by atmospheric winds and 75 brought down by precipitation. These orthophosphate phosphorus concentrations in the precipitation were higher than from the subsurface drainage waters. Both treatments observed tile drainage outflow concentrations of 0.09 ppm orthophosphate phosphorus in April, 1990. The SI treatment decreased to 0.03 ppm orthophosphate phosphorus in June, 1990, and increased with the increased tile drainage outflow through July and August to 0.26 ppm, the highest average concentration found from the SI treatment during both growing seasons. The DO treatment decreased to 0.05 ppm orthophosphate phosphorus in June, 1990, and increased with the increased tile drainage outflow through July and August to 0.30 ppm, which was the highest observed in the DO treatment tile drainage outflow. The concentrations in the DO treatment tile drainage outflow remained above 0.20 ppm through October, 1990. In August, 1990, a DO treatment tile water sample had an orthophosphate phosphorus concentration of 1.02 ppm, the only tile drainage sample found to exceed the 1.0 ppm recommended maximum concentration level. The.orthophosphate phosphorus concentrations in tile drainage from the SI an DO treatments remained around 0.11 ppm from May through July, 1991.~ The SI treatment observed a small increase to 0.15 ppm orthophosphate phosphorus in September, 76 1991, which was when the SI treatment was put in drainage mode for the remainder of the season. This subsurface drainage water may have leached out higher concentrations of orthophosphate phosphorus from the soil. The DO treatment average monthly orthophosphate phosphorus concentrations in tile drainage increased to 0.20 ppm in August, 1991. Minimal tile drainage outflow occurred from the DO treatment June through October, 1991. The increase in orthophosphate phosphorus concentrations in tile drainage outflow during August, 1991, followed the same trend observed with both the SI and DO treatments in 1990. This may result from the corn using less orthophosphate phosphorus, thus rendering residual phosphorus susceptible to leaching. The 1990 growing season average monthly potassium concentrations were considerably higher in tile drain outflow from the SI treatment than from the DO treatment every month except July, 1990. Potassium concentrations in the SI treatment tile drainage outflow were high in the spring, decreased.substantially'byIJuly, 1990, and then increased from August through October, 1990. In October, 1990, the highest average patassium concentration of 18.3 ppm was observed in the SI tile drainage outflow. The DO treatment had no trend in the tile drainage outflow potassium concentrations for the 1990 growing season. Potassium behaves similarly to phosphorus with regard to being 77‘ tied up by microbial activity in the soil. But potassium is readily lost by leaching, even to the extent that the amount leached may equal that used by the crop (Lyon et a1., 1952). Potassiummwill move through the soil in large quantities under saturated conditions. It is possible that since the SI treatment soil profile was saturated up to 0.6 m below the soil surface and moist almost to the surface, and the DO treatment had a water table kept at or below tile drain depth, more potassium would be lost through the SI treatment than from the DO treatment. The 1991 growing season SI treatment observed high average monthly potassium concentrations in the tile drainage outflow from May through July, but decreased as tile drainage from the SI treatment increased August.through.0ctober, indicating that the corn may have used up most of the potassium, leaving little residuals susceptible to leaching when the SI treatment was put in drain mode. The :monthly' average :nitrate :nitrogen, orthophosphate phosphorus, and potassium concentrations in surface drainage outflow from the SI, DO and ND treatments are presented in Tables 10, 11, and 12, respectively. The 1990 growing season Ihighest. monthly’ average nitrate nitrogen concentration from the SI treatment surface drainage was 14.9 ppm in July. The DO treatment observed its highest 78 Table 10. SI surface drainage nutrient concentrations Hog-N, ppm P0,-P, ppm K, ppm gong; g MEAN MIGM egg MEAN urea 19! MEAN HIGH egg 1990 May 0 - - - - - - - - - June 2 14.6 20.5 8.7 0.01 0.02 0.00 13.1 19.5 6.7 July 5 14.9 20.9 4.5 0.13 0.16 0.09 9.9 21.4 3.2 August 3 4.9 8.9 1.8 0.31 0 35 0.22 5.4 5.9 4 4 Sept 2 5.0 7.0 2.9 0.24 0.24 0.23 6.9 9.4 4.4 October 1 1.5 - - 0.25 - - 12.9 - - 1991 May 4 8.3 21.1 0.2 0.19 0.26 0.10 6.8 16.3 0.5 June 0 - - - - - - - - - July 2 1 0 1.0 0.9 0 11 0.11 0.10 1.6 1.6 1 6 August 4 0.9 1.6 0.9 0.11 0.12 0.11 6.3 22.6 0.5 Sept 0 - - - - - - - - - October 2 1.5 2.0 1.5 0.11 0.15 0.07 0.5 0.5 0.5 Table 11. DO surface drainage nutrient concentrations Mos-N, ppm P0,-P, ppm K, ppm Month 9 MEAN HIGH ng M AM HIGH Lg! MEAN MIOM L93 1990 May 1 2.1 - - 0.04 - - 2.6 - - June 0 - ~ - - - - - July 3 4.2 5.8 3.0 0.12 0.16 0.09 4.9 5.0 3.7 August 4 1.1 1.6 0.7 0.31 0.35 0.21 2.9 3.5 2.4 Sept 3 14.9 37.0 1.5 0.24 0.24 0.23 8.3 12.6 6.1 October 5 1.1 1.3 0.7 0.23 0.26 0.21 9.5 12.5 5.8 1991 May 6 9.5 30.2 0.5 0.15 0.19 0.12 7.6 18.4 1.6 June 0 - - - - - - - - - July 2 1 0 1.0 0.9 0.12 0.13 0.10 10.5 12.1 8 9 August 4 0.9 1.6 0.4 0.11 0.11 0.10 0.9 1.1 0.5 Sept 0 - - - - - - - - - October 2 1 1 1.1 1 1 0.15 0.16 0.14 1.0 1.6 0.5 monthly average surface drainage nitrate nitrogen concentration of 14.9 ppm in September, which was when the ND treatment high of 16.0 ppm occurred. The surface drainage outflow nitrate nitrogen concentrations were much lower from all three treatments for the 1991 growing season. All three treatments observed highest 1991 average monthly surface drainage nitrate nitrogen concentrations in 79 Table 12. ND surface drainage nutrient concentrations N03-N , ppm PO4-P , ppm X , ppm Neath A__ MEAN ELEM LEN MEAN ELEM LEN MEAN HIGH LEN 1990 May 0 - - - - - - - - - June 0 - - - - - - - - - July 6 3.6 8.6 0.5 0.11 0.19 0.09 5.2 9.4 2.1 Aug 6 4.9 17.8 0.4 0.29 0.35 0.20 3.6 5.0 2.4 Sept 5 16.0 30.9 1.4 0.24 0.24 0.23 11.8 19.5 8.3 Oct 2 2.2 3.0 1.4 0.21 0.22 0.20 24.0 29.5 18.5 1991 May 6 4.6 31.3 1.1 0.09 0.14 0.00 8.4 21.5 1.6 June 0 - - - - - — - - - July 2 0.6 0 6 0.6 0.18 0.18 0.18 1.1 1.1 1.1 Aug 4 0.6 1.3 0.0 0.12 0.13 0.11 2.8 4.8 1.1 Sept 0 - - - - - - - - - Oct 2 0.8 1.0 0.6 0.16 0.16 0.15 1.6 2.1 1.1 May. The SI treatment had 8.3 ppm, the DO treatment had 9.5 ppm, and the ND treatment had 4.6 ppm nitrate nitrogen found in the surface drainage outflow. There was little difference in monthly average orthophosphate phosphorus concentrations from the surface drainage outflow of the three treatments. The 1990 concentrations in surface drainage outflow increased in August, September and October due to the heavy rains that occurred over that period. The concentrations remained relatively the same through out the 1991 growing season. 80 The highest 1990 monthly average potassium concentration in the SI treatment surface drainage outflow was 13.1 ppm which was measured in June. The highest 1990 monthly average potassium concentration in the DO treatment surface drainage was 9.5 ppm, and 24.0 ppm in the ND treatment surface drainage, which were both measured in October. Both the DO and ND treatments observed highest surface drainage potassium concentrations in September and October, 1990. Although the heaviest rains occurred in August, 1990, the heaviest potassium concentrations in surface drainage outflow from the DO and‘ND treatments did not occur until the soil profile became saturated with the continued high rainfall from September through October, 1990. The SI! treatment rendered more potassium to leach in tile drainage outflow'than from surface.drainage outflow due:to the very wet soil conditions that were maintained during subirrigation. The potassium concentrations removed in the DO surface drainage were not much different than removed from the DO tile drainage. Having open subsurface drainage did not allow the soil profile in the DO treatment to become saturated. This prevented less leaching of potassium to tile drainage outflow from the D0 treatment than from "the SI treatment. The 1991 growing season monthly average surface drainage potassium concentrations were generally lower from all three 81 treatments. The 1991 highest average monthly potassium concentration from the SI treatment surface drainage was 6.8 ppm measured in May. The DO treatment highest concentration of 10.5 ppm occurred in July, and the ND treatment highest concentration of 8.4 ppm occurred in May. Table 13. SI Treatment Monthly Drainage Nutrient Loadings Tile Drainage Surface Drainage Nos-N 90,-? K NO3-N 120,-? 14 Month kq/ha kq/ha 1990 May' - - — - - - June 0.07 0.003 0.19 0.016 0.0000 0.009 July 1.32 0.008 0.69 0.017 0.0003 0.012 August 0.07 0.003 0.23 0.443 0.0242 0.432 September 2.61 0.030 2.30 0.013 0.0010 0.047 October 1.17 0.010 0.81 - - - Total8 5.24 0.054 4.22 0.489 0.0255 0.500 1991 ‘ May 0.192 0.002 0.135 0.010- 0.000 0.008 June 0.000 0.000 0.000 0.000 0.000 0.000 July 0.000 0.000 0.002 0.001 0.000 0.002 August 0.002 0.000 0.011 0.003 0.001 0.016 September 0.012 0.004 0.086 0.000 0.000 0.000 October 0.001 0.000 0.001 0.001 0,000 0.000 Total8 0.207 0.006 0.235 0.015 0.001 0.026 (Oct 1991 = Oct 1 - Oct 6, 1991) The 1990 and 1991 growing season monthly nutrient loadings in surface and tile discharge from the SI, DO and ND treatments are presented in Tables 13, 14 and 15, respectively. The total cumulative nitrate nitrogen loadings measured in both surface and tile drainage are shown in Figure 9. The 1990 accumulated nitrate nitrogen loadings from the SI treatment was 5.73 kg/ha, 13.90 kg/ha from the DO treatment, and 3.42 kg/ha from the ND treatment. The SI treatment 82 16 —- Subirrigation --- Drainage Only 14_ ---- No Drainage .1 I 12‘ I I I 109 I kg/ha on 1 4 .2 2 — p’F-J’S/ ' .b—J Ft;_“:_ -:'__M::__- 0 I I I I I I I I I I I I I MAY JUN JUL AUG SEP OCT NOV MAY JUN JUL AUG SEP OCT NOV 1990 _ 1991 Figure 9. Total Drainage Nitrate-N Loadings through controlling the ‘water table reduced the nitrate nitrogen loadings loss through overall drainage by 59% compared to the DO treatment, and increased loadings by 40% compared to the ND treatment. The 1991 growing season total cumulative nitrate nitrogen loadings from both surface drainage and tile drainage for the SI treatment was 0.23 kg/ha, 0.30 kg/ha for the DO treatment, and 0.03 kg/ha from the ND treatment. The SI treatment reduced the nitrate nitrogen loadings loss through overall drainage by 30% compared to the DO treatment, and increased loadings 87% compared to the ND treatment. 83 Table 14. DO‘Treatment Monthly Drainage Nutrient Loadings Tile Drainage Surface Drainage NO3-N 90,-? K NO3-N 90,-? x Mgnth ka/ha kalha 1990 May - - - 0.003 0.0000 0.002 June 0.32 0.002 0.27 0.004 0.0002 0.009 July 0.19 0.000 0.06 0.053 0.0012 0.049 August 0.79 0.007 0.13 0.070 0.0193 0.209 September 7.43 0.030 1.00 0.053 0.0131 0.383 October 5.99 0.018 0.49 - - - Total8 13.72 0.057 1.96 0.183 0.0338 0.652 1991 May 0.211 0.002 0.032 0.010 0.009 0.132 June 0.029 0.000 0.005 0.000 0.000 0.000 July 0.025 0.000 0.007 0.000 0.000 0.000 August 0.014 0.000 0.005 0.002 0.000 0.002 September 0.006 0.000 0.006 0.000 0.000 0.000 chober 0.000 0.000 0.000 0.001 0.000 0.001 Total= 0.285 0.002 0.054 0.013 0.009 0.135 (Oct 1991 = Oct 1 — Oct 6, 1991) Schwab, et al. (1980) reported that subsurface drainage increased nitrate nitrogen by 35% compared to a surface drainage only treatment. Jacobs and Gilliam (1985) reported that subsurface drainage increased nitrate nitrogen loadings by 82% compared to a surface drainage system. Campbell, et al., (1985) reported a 39% decrease in total nitrate nitrogen loadings from a subirrigation system compared to a water furrow system. Gilliam and Skaggs (1986) reported a 47% reduction in total nitrate nitrogen loadings from controlled drainage compared to conventional subsurface drainage. Deal, et al. (1986) predicted a 33% reduction in nitrate nitrogen loadings from controlled drainage compared to conventional drainage using DRAINMOD. Skaggs and.Gilliam (1981) predicted a 38% reduction in nitrate .nitrogen loadings from a drainage treatment controlled during 84 Table 15. No Drainage (ND) Treatment. Monthly Drainage Discharge Nutrient Loadings ND . N03-N PO4-P K Mpnth, kq/hg 1990 May - - - June ~ 0.00 0.000 0.00 July 0.01 0.000 0.02 August 2.29 0.116 1.24 September 1.12 0.014 0.66 OctOOeg - - - Total- 3.42 0.131 1.92 1991 May 0.0313 0.000 0.026 June 0.0000 0.000 0.000 July 0.0002 0.000 0.000 August 0.0123 0.001 0.008 September 0.0000 0.000 0.000 Ogtobe; 0 0007 0.000 0.002 Total: 0.0334 0.001 0.036 (Oct 1991 = Oct 1 - Oct 6, 1991) the winter compared to a conventional drainage treatment with both having good surface drainage provided. When controlled drainage was practiced all year, the reduction was 64%. For fields with poor surface drainage, the loadings from the drainage treatment controlled during the winter were reduced by 18%, and were the same when drainage was controlled all year. The months with highest tile outflow volumes from both the SI and DO treatments also contained the highest nitrate nitrogen loadings. The highest accumulated monthly nitrate nitrogen loading in SI tile drainage outflow Of 2.61 kg/ha occurred in September, 1990, which is when the SI treatment was put into drainage mode for the season. The highest DO tile drainage nitrate nitrogen loading of 7.43 kg/ha ‘was measured in 85 The increased loadings were attributed to September, 1990. the increased tile drainage outflow caused by the high rainfall events in August through October. The 1991 tile drainage nitrate nitrogen loadings Observed the same trend as in 1990 for both the SI and DO treatments, but the values were much lower due to much lower tile drainage outflow. 16 — Subirrigation --- Drainage Only 14— I 12~ 10-4 I kg/ha l I MAY 1 JUN I T I T JUL AUG SEP OCT NOV 1991 MAY 1 JUN l T T T T JUL AUG SEP OCT NOV 1990 Figure 10. Tile Drainage Nitrate-N Loadings The 1990 and 1991 growing season cumulative nitrate nitrogen loadings in tile drainage waters from the SI, DO and ND The accumulated nitrate treatments are shown in Figure 10. nitrogen loading in the SI tile drainage water was 5.24 kg/ha, The SI and 13.72 kg/ha from the DO tile drainage outflow; e" '0 f a 0"» c7 86 tile drainage nitrate nitrogen loading from June through October was 62% less from the SI treatment than from the DO treatment. The 1991 growing season accumulated SI tile drainage nitrate nitrogen loading was 0.21 kg/ha, and 0.29 kg/ha from the DO tile drainage outflow. The SI treatment reduced nitrate loadings in tile drainage outflow by 25%. Gilliam, et al. (1979) reported a 88% reduction of nitrate nitrogen loadings in subsurface drain flow from controlled drained fields with moderately well drained soils compared to conventional subsurface drained fields of similar soil type. The reduction was approximately 50% for poorly drained soils. Deal, et al. (1986) predicted a 42% reduction in subsurface drainage nitrate nitrogen loadings of a controlled drainage treatment compared to a treatment under conventional subsurface drainage. Evans and Skaggs (1989) reported a 87% reduction in subsurface drain nitrate nitrogen loadings from a controlled drained treatment compared to a treatment under conventional drainage. The highest 1990 growing season monthly nitrate nitrogen loadings in surface drainage outflow occurred during the :months with the highest monthly surface drainage outflow for all three treatments. The SI treatment highest surface «trainage outflow occurred in August, and contained 0.44 kg/ha 87 nitrate nitrogen. The DO treatment highest monthly surface drainage occurred in September, and contained 0.07 kg/ha nitrate nitrogen. The ND treatment also had the highest drainage outflow in September, and contained 3.42 kg/ha nitrate nitrogen. For the 1991 growing season, surface drainage outflow nitrate loadings were substantially less. The highest monthly loadings from all three treatments occurred in May, 1991, and did not exceed 0.03 kg/ha. 4.0 — Subirrigation --- Drainage Only 3_5_ -— No Drainage / l 3.0- l- .l 2.5-1 l’ e I \ 2.0- I 0” “ l 15— I I 10— l 0.5-1 r 0,0 I l l N l l l I .I_...._l_.._'._..l__.l MAY. JUN JUL AUG SEP OCT NOV MAY JUN JUL AUG SEP OCT NOV 1990 1991 Figure 11. Surface Drainage Nitrate-N Loadings The accumulated loadings of nitrate nitrogen in surface drainage discharge are shown in Figure 11. The 1990 accumulated nitrate nitrogen loading in surface drainage discharge from the SI treatment was 0.49 kg/ha, 0.18 kg/ha 88 from the DO treatment, and 3.42 kg/ha from the ND treatment tile drainage water. The 1991 SI treatment had accumulated 0.21 kg/ha nitrate nitrogen in surface drainage outflow, the DO treatment had 0.29 kg/ha, and the ND treatment had 0.03 kg/ha. These loadings were much lower than from the 1990 growing season due to the lack of substantial surface drainage outflow. Jacobs and Gilliam (1985) reported that subsurface drainage substantially reduced surface drainage nitrate nitrogen loadings by 32 fold. Campbell, et al. (1985) reported that controlled drainage had 446% less nitrate nitrogen in surface drainage water than from a water furrow irrigation system surface drainage. Deal, et al. (1986), predicted using DRAINMOD that controlled drainage would increase nitrate nitrogen loadings in surface drainage by 26% compared to conventional subsurface drainage. Deal, et al. (1986), predicted a 26% reduction in nitrate nitrogen loadings in surface drainage from a controlled subsurface drainage treatment compared to a conventional drainage treatment. ENans and Skaggs (1989) predicted a 89% reduction in contrOlled subsurface drained surface drainage nitrate nitrogen loadings compared to conventional subsurface drainage. .Nitrate nitrogen is a highly soluble mineral and moves into the soil profile quite readily. It was expected that the tile 89 drained treatments would contain substantially less amount of nitrate concentrations in the surface drainage water. The DO treatment most likely leached much Of the nitrate nitrogen in the soil profile through the tile drains whereas the SI treatment restricted leaching of nitrate nitrogen into the tile drainage by holding the water in the field. Nitrate nitrogen in the ND treatment either must stay in the soil profile or be removed by surface waters, which would explain the high loadings observed in the surface drainage outflow from the ND treatment. It is possible that.more careful regulation of the water table depth of the subirrigated treatment. through opening and closing the headstand gradually can further decrease nitrate concentrations and loadings, ‘particularly in climates the North Central regions of the United States. The total volume of nitrate would be spread over a longer interval with gradual lowering of the‘water table, thus lessening the concentrations and loading over a single short span of time due to decreased drainage flow rates. This would be important during periods of high rains such as experienced in 1990, as the potential for flushing of nitrates would be high. Another important consideration would be the lowering of the ‘water table to facilitate harvest. It would be to the farmers Iadvantage to lower the water table gradually beginning late in the growing season and continuing until the desired water 90 table depth is reached. It may be hypothesized that the high initial (April, 1990) concentrations of nitrate found in the DO tile'drain outflow resulted from nitrate that was in solution in the soil water and.was flushed out in the drainage outflow, which normally accompany the spring thaw and rains. Thus it would appear that control of the drainage during the spring at which time intense drainage flows usually occur might reduce spring discharge nitrate nitrogen loadings. 0.14 — Subirrigation --- Drainage Only / -- No Drainage /' 0.12— / 040- / 0.08-* o .C \ 05 x 0.06-‘ 0.04-* 0.02% : f 0-00 I I I I I I I I I I T_“I‘-_‘I MAY JUN JUL AUG SEP OCT NOV MAY JUN JUL AUG SEP OCT NOV 1990 1991 Figure 12. Total Drainage Orthophosphate-P Loadings The.cumulative orthophosphate phosphorus loadings in surface and tile drainage waters from the SI, DO and ND treatments are shown in Figure 12. The 1990 growing season total orthophosphate phosphorus loadings from both surface drainage 91 and tile drainage for the SI treatment was 0.08 kg/ha, and 0.09 kg/ha for the DO treatment. The total orthophosphate phosphorus loadings from the surface drainage of the ND treatment was 0.13 kg/ha. The SI treatment orthophosphate phosphorus loadings in overall drainage waters was 11% less than in the DO treatment drainage waters, and 38% less than from the surface drainage waters in the ND treatment. For the 1990 growing season, in both tile drained treatments, a reduction in orthophosphate phosphorus loadings was observed compared to the treatment with no tile drains. The 1991 growing season total orthophosphate phosphorus loadings for the SI treatment was 0.006 kg/ha, 0.011 kg/ha for the DO treatment, and 0.001 kg/ha for the ND treatment. Accuracy of such low values is questionable, thus conclusions are impossibLe to make when comparing these loadings with those found during the 1990 growing season. Baker, et al. (1975) did report loadings of up to three significant factors but these measured values were not used in any comparison study. Schwab, et al. (1980) reported that subsurface drainage decreased total phosphorus loadings in drainage water by 83% compared to a surface drainage system. Bengtson, et al. (1988) reported that subsurface drainage reduced total phosphorus loadings in drainage water by 56% compared to a surface drainage only treatment. Campbell, et al. (1985), 92 007 — Subirrigation --- Drainage Only 0.06- ,r I 005~ 0.04“ I O l .c f \. I 3 I‘ 003— I I I l I 002— ll l I l I 0014 f 900 I I I I I I I I I I I I I JUL AUG SEP OCT NOV MAY JUN JUL AUG SEP OCT NOV 1991 MN! JUN 1990 Figure 13. Tile Drainage Orthophosphate-P Loadings reported that subirrigation reduced total orthophosphate Deal, et al. (1986), loadings in drainage water by 156%. reported that controlled drainage reduced total phosphorus by Evans and 4% compared to conventional subsurface drainage. Skaggs (1989) reported a 53% reduction in controlled drainage phosphorus loadings compared to conventional drainage. The cumulative orthophosphate phosphorus loadings in tile The 1990 growing drainage outflow are shown in Figure 13. season SI tile drainage outflow had 0.05 kg/ha orthophosphate The loadings, and 0.06 kg/ha in the DO tile drainage water. 1991 cumulative orthophosphate phosphorus loading in the SI tile drainage water was 0.006 kg/ha, and 0.002 kg/ha in the DO 93 treatment. There was very little difference between the SI and DO treatment tile drainage cumulative orthophosphate phosphorus loadings during both growing seasons. Although Figure 13 would suggest that the SI increased tile drainage water loadings of orthophosphate phosphorus compared to the DO treatment, these values are too small to draw definitive conclusions. Deal, et al. (1986), predicted a 12% decrease in controlled drainage subsurface drainage total phosphorus loadings. Evans and Skaggs (1989) reported a 24% reduction in controlled subsurface drainage phosphorus loadings compared to convectional subsurface drainage. The cumulative orthophosphate phosphorus loading in surface drainage discharge are shown in Figure 14. The 1990 growing season orthophosphate phosphorus surface drainage loadings from the SI was 0.026 kg/ha, 0.034 kg/ha from the DO treatment, and 0.131 kg/ha from the ND treatment surface drainage water. The 1991 cumulative orthophosphate phosphorus loading in the SI surface drainage water was 0.001 kg/ha, 0.009 kg/ha from the DO treatment, and 0.036 kg/ha from the ND treatment. The 1990 surface drainage orthophosphate phosphorus loadings were highest from all three treatments in August, which is when surface drainage outflow had increased from previous months due to the August high rainfall events. The 1991 surface drainage orthophosphate phosphorus loadings 94 0A6 — Subirrigation --- Drainage Only 0.14_ -- No Drainage 012- / 0.10-l I 0.08 - I kg/ho 006- I 004— l 0.02 'l r I I 0.00 I I I I I I I I I I I I MAY JUN JUL AUG SEP OCT NOV MAY JUN JUL AUG SEP OCT Nov 1990 1991 Figure 14. Surface Drainage Orthophosphate-P Loadings were very low but did tend to be relatively higher during months of increased surface drainage outflow. The orthophosphate phosphorus concentrations and loadings found in the 1990 growing season surface drainage outflow from all three treatments were highest when surface drainage outflow was highest. The 1991 low surface drainage outflows did not show this trend as clearly. Since phosphorus is considered a soil bound nutrient, it is usually lost in highest quantities by surface drainage. Bengtson, et al. (1988), reported that subsurface drainage reduced total phosphorus loadings in.surface.drainage‘water by 66% compared to a surface drainage treatment. Campbell, et 95 al. (1985) reported that subirrigation reduced surface drainage orthophosphate loadings by 323% compared to the furrow irrigation system. Deal, et al. (1986) , predicted that controlled drainage would increase surface drainage total phosphorus loadings by 20% compared to conventional drainage. Evans and Skaggs (1989) reported that controlled drainage reduced surface drainage total phosphorus loadings by 71% compared to conventional subsurface drainage. System design and management as described.by Evans and Skaggs (1989) affects the amount of surface drainage, and since phosphorus is a soil bound nutrient susceptible to surface leaching, the reduction of surface drainage volumes through proper management can reduce the phosphorus loadings being discharged at edge of field. Phosphorus is considered to be a difficult mineral to manage in the soil. The total phosphorus amount in an average mineral soil compares favorably with that of nitrogen, however most of the phosphorus present is unavailable to the plant (Lyon et al, 1952). Thus, it is necessary to apply more phosphorus to the soil than the plant can remove. Much of this phosphorus becomes tied up in the soil as either organic or inorganic compounds, or by the active clay fraction of the soil. Rapid decomposition of organic matter and high microbial population in the soil environment results in a temporary tying up of the inorganic phosphorus. 96 The soil at the site may have several factors working together to make phosphorus susceptible to leaching from the soil profile. As the summer crop grows and is in need of the mineral, both organic decomposition and microbial activity are at high levels rendering the phosphorus temporarily unavailable. At the end of the growing season, the soil temperature drops resulting in a drop in both organic decomposition and microbial activity, which in turn frees up some of the phosphorus that has been inactivated. This process occurs when the crop is no longer growing and therefore the phosphorus is removed by leaching or through runoff and erosion. This trend was observed from all three treatments during the 1990 growing season, but was nOt clearly shown during the 1991 growing season due to the low drainage volumes. However, the low concentrations in the soil and water suggests leaching of applied phosphorus does not occur significantly. Total potassium loadings in the tile and surface drainage waters from all three treatments are shown in Figure 15. The 1990 growing season total potassium loadings from both surface and tile drainage for the SI treatment was 4.72 kg/ha, 2.61 kg/ha from the DO treatment, and 1.92 kg/ha from the ND treatment. The SI treatment overall potassium loadings in drainage waters was 45% greater than in the DO treatment drainage waters, and 59% greater than in the ND drainage waters. The 1991 growing season total potassium loadings in 97 5 — Subirrigation --- Drainage Only 5‘ -- No Drainage 4— 4—1 34 2 \3— 0‘ .x 2.— 2—I 1— 1— ' ————— “ ‘4"--- O I I I I I I I I I "—7'—""T"”F--I MAY JUN JUL AUG SEP OCT NOV MAY JUN JUL AUG SEP OCT NOV 1990 1991 Figure 15. Total Drainage Potassium Loadings drainage outflow from the SI treatment was 0.27 kg/ha, 0.18 kg/ha from the DO treatment, and 0.04 kg/ha from the ND treatment. The overall potassium loadings in the SI drainage water was 77% greater than in the DO treatment drainage waters, and 85% greater than in the ND drainage waters. Schwab, et al. (1980) reported that subsurface drainage reduced potassium loadings in drainage water by 42% compared to a treatment that has no subsurface drainage. Bengtson, et al. (1988), reported that subsurface drainage reduced potassium loadings in drainage water by 24% compared to surface drainage only treatments. Both studies attributed the 98 differences in the loadings carried by the surface drainage of the two different drainage treatments, subsurface drainage loadings were found to be less substantial than was found in this study. Since potassium leaches readily through the soil in larger quantities under saturated conditions, the SI treatment lost more potassium in tile.drainage outflow than the DO treatment, and both tile drained treatments increased the loadings of potassium in drainage water compared to the treatment with no tile drains. 5.0 —— Subirrigation --- Draino e Onl 4.5-I g y 4.0 - 3.5- 3.0 1 2.5 ~ kg/ha 2.0d 1.5“ 1.0-* 0'57 T I I I I I I F"'F"‘T"'7'-'-F---T' MAY JUN JUL AUG SEP OCT NOV MAY JUN JUL AUG SEP OCT NOV 1990 1991 0.0 Figure 16. Tile Drainage Potassium Loadings 99 The cumulative potassium loadings in tile drainage outflow are shown in Figure 16. The 1990 growing season cumulative tile drainage potassium loadings from the SI treatment was 4.22 kg/ha, and 1.96 kg/ha from the DO tile drainage water. The 1991 growing season cumulative potassium loading in the SI tile drainage water was 0.24 kg/ha, and 0.05 kg/ha in the DO tile water. As with the other nutrients taken and analyzed during the 1991 growing season, the potassium loadings in the tile drainage waters are low. For both growing seasons, the highest monthly tile drainage outflow yielded the highest monthly potassium loadings. The cumulative potassium loadings in surface drainage discharge are shown in Figure 17. The 1990 growing season loadings from the SI treatment was 0.50 kg/ha, 0.65 kg/ha from the DO treatment, and 1.92 kg/ha from the ND treatment. Potassium readily leaches through the soil in large quantities under saturated conditions. The ND treatment had the highest 1990 cumulative surface drainage outflow which resulted in the highest. potassium loadings“ ‘With the increased surface drainage due to no tile drains, the highest potassium loadings would be expected from the ND treatment. The 1991 growing season cumulative potassium loadings were very low as compared to 1990. The surface potassium loading iJIthe SI surface drainage water was 0.036 kg/ha, 0.1345 kg/ha 100 2i) —— Subirrigation I --- Drainage Only 1'8" -- No Drainage I 1.6q 1.4-l .l 12- I kg/ha 1.0m I o.“ I I 0.6 - I [I l— l l T l l l l l I MAY JUN JUL AUG SEP OCT NOV MAY JUN JUL AUG SEP OCT NOV 1990 1991 Figure 17. Surface Drainage Potassium Loadings from the DO treatment, and 0.026 kg/ha from the ND treatment. No correlation can be drawn between surface drainage outflow volumes and the resulting potassium loadings for the 1991 growing season. The highest monthly potassium loading from the DO treatment was greater than 0.13 kg/ha which occurred in May. This was significantly higher than any other 1991 monthly loading measured from all three treatments and may indicate a contaminated sample. Ammonia nitrogen concentrations and loadings were first monitored in the 1991 growing season. The total accumulated ammonia nitrogen loadings in both tile and surface drainage outflow are shown in Figure 18. The total ammonia nitrogen 101 0.040 — Subirrigation --- Drainage Only 0.035_ -— N0 Drainage In" 0.030 -‘ _,——’ ------------ '-J---' r ---------- I 0.025 A I I I 0 I { o.ozo~ l 0‘ I x I I 0.015 -I I I 0.010 - 0.005 - ‘I ' “p.0— — -—- —— — —— — cue-9 '6." _11—»” 0000 I I I I I MAY JUN JUL AUG SEP OCT NOV 1991 Figure 18. Total Drainage Ammonia-N Loadings loading from the SI treatment drainage outflow was 0.0111 kg/ha, 0.0336 kg/ha from the DO treatment, and 0.0048 kg/ha from the ND treatment. The 1991 growing season ammonia nitrogen tile drainage Table 16. Tile drainage ammonia-N concentrations and loadings Subirrigation Drainage Only N34-" I Ppm "Hf-N I ppm £9333 a Mean fiigh ng kglha 3 Mean High Lg! kgiha May 7 .15 .30 .00 .0008 13 .06 .22 .00 .0013 June 21 .17 .90 .00 .0000 21 .27 .97 .00 .0002 July 16 .28 .55 .04 .0003 12 .13 .43 .00 .0004 Aug 11 .25 .37 .19 .0011 9 .33 .66 .22 .0030 Sept 11 .22 .26 .19 .0054 4 .53 .67 .39 .0005 Oct 1 .48 .0003 1 .25 .990; Total8 .0079 .0055 1(32 concentrations and loadings are presented in Table 16 . The cumulative ammonia nitrogen loadings are shown in Figure 19. The SI tile drainage outflow contained 0.008 kg/ha ammonia nitrogen, and the DO tile drainage outflow contained 0.006 kg/ha. 0.009 — Subirrigation --- Drainage Only 0.008“ 0.007 -« 0.006-* 0.005 ‘ kg/ho 0.004 - 0.003 - 0.002 - 0.001 - I 0000 I j 1 , 1 MAY JUN JUL AUG SEP OCT NOV 1991 Figure 19. Tile Drainage Ammonia-N Loadings The 1991 growing season ammonia nitrogen surface drainage concentrations and loadings are presented in Table 17. The cumulative ammonia nitrogen loadings are shown in Figure 20. The cumulative ammonia nitrogen loadings in surface drainage outflow was 0.003 kg/ha, 0.028 kg/ha from the DO treatment, and 0.005 kg/ha from the ND treatment. The high surface drainage ammonia nitrogen loadings in the DO treatment 103 Table 17. Surface drainage ammonia-N concentrations and loadings Subirrigation / Controlled Drainage (SI) NH‘-N, ppm Month g Mean H'gh L93 kgiha May 4 1.05 0.76 0. 1 0.0011 June 0 ---- ---- ---- - ----- July 2 0.15 0.16 0.14 0.0002 Aug 4 0.88 0.27 0.65 0.0014 Sept 0 ---- ---- — — Oct 2 0.76 0.96 0.56 0.0005 Total: 0.0032 Conventional Subsurface Drainage Only (DO) NH4-N, ppm Month 3 Mean High Low k ha May 5 9.64 46.37 0.37 0.0266 June 0 ---- ----- --—- ------ July 2 0.17 0.20 0.13 0.0000 Aug 4 0.50 0.66 0.35 0.0010 Sept 0 ---— ----- Oct 3 0.68 0.81 0.50 0.0005 Totals 0.0281 No Subsurface Drainage (ND) NH4-NI Ppm Month 2 Mean H'gh L9! kglha May 5 0.75 2.01 0.29 0.0032 June 0 ---- -—-- — July 1 0.18 0.0000 Aug 4 0.47 0.56 0.34 0.0012 Sept 0 ---- ---- --—— ------ Oct 4 0.48 0.59 0.34 0.0004 Total= 0.0048 predominantly occurred in May. Due to many problems encountered with the suction lysimeter used for both growing season, there were very few samples collected. The soil water nutrient concentrations of the samples collected are presented in the raw data form in Appendix D. The soil water data do not show trends that can be attributed to the research treatments. The soil nutrient laboratory analysis results are presented in Appendix E. The 1990 data includes samples collected from 104 0.040 —- Subirrigation —-— Drainage Only 0035— -"- No Drainage 0.030— .9 —————— I ---------- '—'-. r ________________________ 0.025— I I E \ 0.020— 3' I I 0.015- 0010- I I 0.005— v’m--_/--—F-a—i_--——- I_,_.,_,/—--_________-_’ : ‘/———/_ 0.000 1/ I I I I I MAY JUN JUL AUG SEP OCT 1991 Figure 20. Surface Drainage Ammonia-N Loadings NOV north and south replications in the SI and DO treatments, and east and west replications in the ND treatment. In 1991, all treatments had a north, south, east and west replication from which soil samples were collected. 500 O Subirrigation )K Drainage Only - No Drainage 400‘ II .. I 300 O ' u i " ‘5 u: 200- - O O - - - I O 100- 9 c an 3‘ ..; U I o C a 8 8 ° " ' Q I O I I I I é e; b I I I I l é APR MAY JUN JUL AUG 5 P O T N V MAY JUN JUL AUG 3 P 01 1 990 1 99 1 Figure 21. Soil Nitrate Nitrogen Loadings, 0.0-0.3m 105 O Subirrigation K Drainage OnIy - No Drainage 400 -‘ GOO - i 200 - 1 OO -‘ ~ I . I 3" g "' I a O —J . B O C I g ‘ g 1 U o T I é a 6 f I I I I APR MAY JUN JUL AUG 8 P O T N V MAY JUN JUL AUG SéP OCT 1 990 1 99 1 Figure 22. Soil Nitrate Nitrogen Loadings, 0.3-0.6m O Subirrigation X Drainage Only - Na Drainage ‘00— 300- 200— TOD-n . I I I I O _ a . o a I as a 0 1 . o O '——-——r———a—r-“—r T é (I: I T W - I 1 I L é APR MAY JUN JUL AUG 5 P O T NOV MAY JUN JUL AUG S F’ 0131' 1990 1991 Figure 23. Soil Nitrate Nitrogen Loadings, 0.6-0.9m The nitrate nitrogen loadings from the soil samples taken over both growing seasons are shown in Figures 21 through 23. These are the average loadings of the replications within each treatment. The 1990 nitrate nitrogen loadings for all three treatments showed an increase in the top 0.3m of soil from April to May, which followed the application of fertilizers and early rain events, with the DO treatment having the highest loadings through most of the year. Samples taken in early and mid-June, 1990, had considerably lower nitrate 106 nitrogen loadings. This may be due to the lack of substantial rainfall during the time those soil samples were obtained. The nitrate nitrogen loadings increased considerably in early July which followed rain events that occurred in late June. As the soil dried up through June, less nitrate nitrogen was available in the top 0.3m of soil. With the rain events in lateIJune, nitrate nitrogen loadings increased in soil samples collected in July, 1990. There was a small increase in the 1991 nitrate nitrogen soil loadings in the top 0.3m for all three treatments following fertilizer application in late May, but the loadings were considerably less through the 1991 growing season compared to 1990. Rain events immediately followed the application of fertilizers for both growing seasons. However, in 1990, no rain events occurred following the early May rain.events until the end of June and early July, which may have prevented further movement of nutrients down to the root zone. During this early development stage of corn, this may prove critical in how much of the nutrients the corn will take up, and how much will remain in the soil. In 1991, there were sporadic rains through May and in early June, and this may have moved more nutrients down to the root zone at a critical time in the corn development when nutrient requirements are high. Orthophosphate phosphorus loadings from the soil samples are shown in Figures 24 through 26. .All three treatments followed 107 Figure 26. Soil Orthophosphate-P Loadings, 0.6-0.9m 600 O Subirrigation I Drainage Only - Ne Drainage 400- o I 0 0" a o a 300— u " M O - - he an 2 o o u: 200— a fl - us . - - I I o a 100- I a I - t! ’1 l6 . - I a - o T f T T T T I I T APR MAY JUN JUL AUG séP ocr Nov MAY JUN JUL AUG sap OCT 1990 1991 Figure 24. $011 Orthophosphate-P Loadings, 0.0-0.3m 600 O Subirrigation K Drainage Oniy I No Drainage 400-1 .300— zoo—I iOO-i I ° C a a 0— I‘ll i ‘ 7 7 ' ' APR MAY JUN JUL AUG SEP oGT Nov MAY JUN JUL AUG séP 04:1 ‘990 1991 Figure 25. 8011 Orthophosphate-P Loadings, 0.3-0.6m 500 O Subirrigation M Drainage Only . No Drainag- 400—1 300-1 200- 1oo—+ a I a 0‘ i- - T l I i 1: APR MAY JUN JUL AUG sép ob: Nov MAY JUN JUL AUG Sb:- OCT 1990 1991 108 similar trends in the top 0.3m of soil with the tile drained treatments consistently having higher orthophosphate loadings than the ND treatment through most of both growing seasons. The 1990 loadings were slightly higher than in 1991. 1°00 O Subirrigation K Drainage Only I Bio-Drainage BOO—l O M II II I 0004 O O ~ - M i ° ' o I M - 400— O I 0 I I ‘5 u 200— O . U - I M O I I I I I I I I I I I I I APR MAY JUN JUL AUG SEP OCT NOV MAY JUN JUL AUG SEP 0‘31' 1 990 1 991 Figure 27. Soil Potassium Loadings, 0.0-0.3m 1000 O Subirrigation M Drainage Only 3 Na Drainage GOO-- GOO—1 i 400— — - I ° ”I I zoo-«ia Bul-- _ _II§- ! ° . I o O O O o I I fl T I I I a I I I I I I APR MAY JUN JUL AUG SEP OCT NOV MAY JUN JUL AUG SEP OCT 1 990 1 99 1 Figure 28. Soil Potassium Loadings, 0.3-0.6m Potassium loadings from the soil samples are shown in Figures 27 through 29. The soil potassium loadings were slightly lower in 1991 than in 1990. Although the data from the soil samples does not show trends that can be attributed to the treatments or utilization, the nitrate nitrogen, 109 100° O Subirrigation M Drainage Only 8 Na Drainage BOO- 00°- ‘00— M ' O a O 200- ' - ° I I u 3 U o ii a i C . I . I - II ' O I I I I I I I = I fi I I r I AF'R MAY JUN JUL AUG SEP OCT NOV MAY JUN JUL AUG SEP 0131' 1 990 1 99 1 Figure 29. Soil Potassium Loadings, 0.6-0.9m orthophosphate phosphorus and potassium loadings in the top 0.3m of soil were lower in 1991 than in 1990. This may be due to the sporadic early rains in May and early June following the 1991 fertilizer application, which moved the nutrients to the root zone during a period of high nutrient requirements by the corn. The lack of sporadic rains for over a month following the 1990 fertilizer application may have prevented the movement of fertilizers to the root zone during a critical period of high nutrient requirements for corn. The 1991 ammonia nitrogen loadings from the soil samples are shown in Figures 30 through 32. The data from the soil samples does not show trends for nutrient transport.that can be attributed.to the treatments or utilization. However, the data suggests that nutrient loadings below 0.6m are not substantially measured due to surface application of fertilizers. 'This is likely due to the 110 .0 O Subirrigation M Drainage Only 3 Na Drainage ao-n ‘0— a a I ' J a g .o .. I a a I H N O a 20 -— o . . c: - I 1o- 3 °.... Jam Jot Also sép as Nov 1991 Figure 30. Soil Ammonia Nitrogen Loadings, 0.0-0.3m 00 O Subirrigation K Drainage Only 3 Na Drainage 50—4 ‘0 —-I a a 5 30— "' z I 20 a ° - a g a U I 1(3— - a ' I °mv «3.. Jul Jo sép 0.57 Nov 1991 Figure 31. Soil Ammonia Nitrogen Loadings, 0.3-0.6m 80 O Subirrigation N Drainage Only 9 Na Drainage :0— 4.0—. I a a g 30— O I 20. a _ ° 9 II ~ I 10- I = o i 1 i 1 MAY JUN JUL AUG st? OCT NOV 1991 Figure 32. Soil Ammonia Nitrogen Loadings, 0.6-0.9m 111 soil being very compact with low hydraulic conductivity at the 0.6 to 0.8m depth. Alachlor Laboratory analysis data for all soil samples analyzed for alachlor is presented in Appendix F. Limited analysis was performed on the soils due to the high cost of the procedure. Alachlor concentrations in tile and surface drainage water from the treatments are presented in Table 18. The concentration of alachlor in water samples collected exceeded the Environmental Protection Agency limit of 2 ppb except for the last tile drainage sample analyzed from both Table 18. Alachlor Loadings and Concentrations in Drainage Water S I DO ND (ppb) (ppb) (ppb) Datg Tile Surface Tile Surface Surface 6/17/91 2.04 7/18/91 6.20 7/24/91 4.09 2.24 6.51 9.74 8/10/91 2.38 2.29 8/17/91 2.65 2.55 8/28/91 1.49 9/4/91 1.26 the SI and D0 treatment. Due to the low frequency of drainage events during the 1991 growing season, the alachlor remained in the field for most of the growing season. Even late in the growing season, alachlor was still in the tile drainage water of both the SI and D0 treatments. The tile drainage sample 112 obtained from the 00 treatment on August 28, 1991, was the first sample from that treatment that was below the EPA drinking water standard of 2 ppb for alachlor. The tile drainage sample obtained from.the SI treatment on September 4, 1991, was the first sample from that treatment to fall below the EPA standard for alachlor. The soil samples analyzed showed no detectable levels of alachlor in the top 0.3m of soil for all treatments which is consistent with Smith, et al. (1990). It is interesting to note that the first soil set analyzed (June 7, 1991) for alachlor were collected within 24 hours of herbicide application. It is probable that the granular herbicide had not yet began to react within the soil environment. Between the collection of the soil set taken on June 7, 1991, and the second set analyzed June 25, 1991, 13 mmlof rainfall occurred. Yet there was no alachlor detected in the top 0.3m of soil. Sample obtained and tested from the D0 tile drainage outflow did contain alachlor, indicating that the some of the alachlor had already been leached to the tile. grog xield and Biomass Table 19 summarizes the 1990 and 1991 crop yields of all three treatments. The field measurements made to determine the crop grain yields for both. growing seasons are presented in Appendix G. Plant emergence for the 1990 growing season in all three treatments was first observed the week of May 22, 1990 firS' trea from trea met: to 1 For fax the SI trg The the ND Th. D0 tr 113 1990. Plant emergence during the 1991 growing season was first observed the week of May 29, 1991. The 1990 SI treatment yield was 2.4 metric tons/ha, 2.2 metric tons/ha from the D0 treatment, and 2.1 metric tons/ha from the ND treatment. The 1991 SI treatment yield increased to 3.0 metric tons/ha, but the D0 and ND treatment yields decreased to 1.9 metric tons/ha, respectively. Table 19. Crop Yield Data Emerged Yield @ 15% M.C. Location plantsLha metric tons/ha 1990: SI 65,000 2.43 00 66,500 2.22 ND 67,000 2.08 1991: SI 66,300 2.96 DO 66,700 1.87 ND 65,800 1.68 For both growing seasons, the SI treatment created more favorable conditions for growing corn and yields were higher than the other two treatments as shown in Figure.34. The 1990 SI yield was 9% higher than that obtained from the D0 treatment, and 17% than that obtained from the ND treatment. The 81 and D0 treatments were harvested November 8, 1990, and the ND treatment was harvested December 23, 1990, due to the ND area being too wet for field operations before that date. The 1991 SI yield was 58% higher than that obtained from the 00 treatment, and 76% higher than that obtained from the ND treatment. All three treatments were harvested on October 8, 1991. Figure 33. The 1991 5] growing Se (Compared improved CC 1991 may h. soil more e the end 0f determine w Profile the trEatmEnts the growng 114 1991. lflUUMHDnNMI Impen- .mOfly laser-ug- (Kernel. lt 16% HOW" Content) Figure 33. Crop Yields The 1991 SI treatment yields were the best observed over both growing seasons. The 1990 SI yield was probably reduced (compared to 1991) because of excess water stress. The improved control of water table depth for the SI treatment in 1991 may have utilized the soil water and nutrients in the soil.more effectivelyu ‘Without significant drainage events at the end of the growing season however, it is impossible to determine whether more nutrients were removed from the SI soil profile than in the other treatments, as none of the three treatments showed significant loss of nutrients by the end of the growing season as was observed in 1990. Foust, et al. (1987) reported than corn silage yields from water table management were highest during periods of drought compar (1989) signif carefu signif sensit table (1984) water reporte soybear The res Table 2 Appendi fared s Slight treatme area in in both treatme treatme rainfal‘ expecte: much hit The plat 115 compared to periods of excessive rain. Evans and Skaggs (1989) emphasized that water table management systems can significantly increase yields when properly designed and carefully managed, but mismanagement of such systems can significantly reduce crop yield. Belcher (1990) stressed the sensitivity of corn production to the management of the water table depth. Sipp, et al. (1984), and Rausch and Nelson (1984), reported crop yield increases under properly managed water table management systems. Carter, et al. (1988) reported that high water table depths had adversely affected soybean, wheat and corn yields. The results of the leaf area index measurements are shown in Table 20. The leaf index field measured data are presented in Appendix G. Although the 1990 yields from the SI treatment fared slightly better than the other treatments, there was a slight decrease in leaf area index for plants in the SI treatment compared to plants in the D0 and ND. ‘The 1991 leaf area index results show that the SI treatment developed crops in both replications with leaf areas greater than in the other treatments. The decrease in leaf area for the D0 and ND treatments resulted from water stress caused by the low rainfall amounts received in 1991. These results ‘were expected since the 1991 crop yield from the SI treatment was much higher than from the other treatments. The plant biomass production results are presented in Table fable 2‘ 7’ Date 7/18/9 8/2/90 6/19/9 7/10/9 7/24/9 21. The than in til the increa had better were slig) leaves of developmer1 August and Table 21‘ \ 7/18/90 8/2/90 6/19/91 7l2‘1/91 Table 20. Leaf Area Index 116 133:3 7/18/90 8/2/90 6/19/91 7/10/91 7/24/91 SI Leaf Index n m2 [m2 70 3.34 70 1.87 70 1.18 70 3.68 70 2.91 D0 Leaf Index n m2 [m2 70 2.46 70 2.13 70 1.06 70 3.10 70 2.02 ND Leaf Index a 1min; 70 2.51 70 2.24 70 0.68 70 2.94 70 2.75 21. The 1990 plant biomass was higher in the SI treatment than in the other treatments. the increase in crop yield suggests that the plants in the SI had better developed plants. were slightly lower in the SI treatment may indicate the leaves of all the treatments were damaged during the latter This slight increase along with The fact that leaf area indexes development stages due to the excessive rains of late-July, August and September. Table 21. Plant Biomass DQEQ 7/18/90 8/2/90 6/19/91 7/10/91 7/24/91 SI Plant Biomass n kglha 70 583.31 70 1219.75 70 328.05 70 640.93 70 1011.82 DO ND Plant Biomass Plant Biomass g kgzha 70 405.15 70 1005.83 70 332.46 70 660.72 70 1098.30 g 70 70 70 70 70 kglha 371.38 958.75 308.67 483.15 641.96 Elk, et a] relations] have on 1 through 01 reported 1 crop yielc‘ growing 5 intermitte yields co constant c' (1931) . re under Shaj reported t Here 10Wer The nutrie ZL In 19 potaSs ium ND tI‘Eatme $011 condi 00111. It ‘ nutrients Present bef ObServed w‘ 117 Elk, et al. (1966) and Sprague (1977) emphasized the delicate relationship water use and other various environmental factors have on the biomass production, leaf area and crop yield through out the entire growing season. ZRitter and Beer (1969) reported that early flooding of corn was most detrimental to crop yield as compared to flooding that.may occur later in the growing season. Lal and Taylor (1969) reported that intermittent flooding early in the growing season reduced corn yields compared to water tables that were maintained at constant depths. Alvino and Zerbi (1986), and Baser, et al. (1981) , reported increased biomass production and grain yields under shallow water table depths. Follett, et al. (1974) reported that corn biomass production and corn grain yields were lower at high and low'water table depth, but maximized at medium water table depths. The nutrient content of plants sampled are presented in Table 23. In 1990, the plant content of nitrogen, phosphorus and potassium were higher in the SI treatment than in the D0 and ND treatments which indicates that the SI treatment created soil conditions that made more nutrients available to the corn. It is important to get water to the crop early in its development in order to help free up some of the unavailable nutrients that were either added by fertilizers or were present before planting. In 1991, the exact opposite trend is observed with plant nutrients. The ND treatment had the highest develop}!!! higher pl nutrient Table 2. [—— Date n fi/% 5 8/8/90 2 7/11/91 2 7/25/91 2 9/4/91 2 The result in Table ; SamPleci fr 0ther tree l”alltrient; treatments, in the SI . "Ore nutriE not get th developing conditions 1 the Do and N higher leVe ‘ 118 highest plant nutrient content through out. most of the development stages. The reason why the ND treatment had higher plant nutrients.may' beldue to the results found in the nutrient content of the kernels analyzed. Table 22. Plant Nutrient Content SI 00 ND Ave Plant Ave Plant Ave Plant Height kg/ha Height kg/ha Height kg/ha 2g: 0 Emu a E. 5 n awe. ! E s 0 Ewe ! 2 5 7/25/90 2 6997.3 65.1 7.0 88.9 2 4438.9 52.8 4.9 59.0 1 3510.8 19.0 2.1 40.0 8/8/90 2 11475.8 117.1 16.1 199.7 2 7863.6 97.5 7.9 100.7 1 8468.8 80.5 6.8 107.6 7111/91 2 6395.7 70.3 9.5 70.9 2 6276.5 94.2 12.4 101.4 2 4257.3 93.3 13.1 107.6 7/25/91 2 10780.4 113.4 13.8 128.2 2 10451.9 126.5 22.1 183.0 2 7034.1 115.0 19.8 217.5 9/4/91 2 8665.5 84.6 11.2 104.9 2 6763.4 91.9 14.6 119.2 2 6336.5 124.0 18.0 217.9 The results of the corn kernel nutrient content are presented in Table 24. In 1990, the nutrient content in the kernels sampled from the SI treatment were slightly higher than the other treatments. But in 1991, the SI treatment kernel nutrient content was substantially higher than the other treatments. With the 1991 plant nutrient content being lowest in the SI treatment, it would appear that the corn utilized more nutrients to its kernels while the other treatments did not get the nutrients from the stem and leaves into the developing ears. This was most likely caused by the dry conditions that existed for most of the 1991 growing season in the D0 and ND treatments. iRattan and.George (1969) found that higher levels of nitrogen, zinc, and copper increased yields under water table management systems with well drained soils. The uptake of N and Zn by corn was reduced by high water able depths a: nutrient Table 2 F’— kg/ha Lee 5 8,61 90 1- 1 9/4/91 2- 2- The result the soil Presented leVel of S growing Se among treat significam treatments to 0. 31D (j Significant subsurface ' treatmem: 119 depths and flooding. Lal and Taylor (1969) reported decreased nutrient uptake under high water table conditions. Table 23. Corn Kernel Nutrient Content SI 00 N0 Ave Kernel Ave Kernel Ave Kernel Height kg/ha Height kg/ha Height kg/ha Date n kglha ! g 5 n-Reg kglha fl 2 K n-Re kg[ha ! g 5 8/8/90 1- 7H 9425.0 126.3 34.9 31 1 1-N 8093.1 118.2 24.3 23.5 1-H 8636. 3 113.1 27.6 25.9 1- -S 9327.5 145.5 37.3 35.4 1-N 8525.3 118.5 31.5 31.5 1-E 8770. 3 142.1 28.1 27.2 9/4/91 2- -H 10347. 4 118.7 35.2 27.4 2-N 7148.2 100.1 32.7 24.1 Z-H 7491. 3 94. 3 31.0 22.8 2- S 12242. 3 145.4 43.4 34.1 Z-S 7974 7 115.7 33.9 24.7 z-s 6484. 6 87. 3 24. 8 24.8 Statistical Analysis The results of the 2-sample t-test statistical comparison of the soil nutrient loadings between the three treatment are presented in Appendix:H. .All tests were run at a significance level of 95%. At the 0.0 to 0.3m soil depth for the 1990 growing season, there was no significant difference found among treatments for the nitrate nitrogen loadings. 'There was significant difference found between the SI and both D0 and ND treatments for orthophosphate phosphorus loadings in the 0.0 to 0.3m depth. Potassium loadings were found to be significantly different at the 0.0 to 0.3m depth between the subsurface drained treatments (SI and D0) compared to the ND treatment. A 2-sample t-test statistical comparison of the crop yields between the three treatment for are presented in Appendix H. For the 1990 growing. season, a comparison was made only between the two subsurface drained treatments because two replication the ND tree farmer due At a conf difference corn grain found betw treatments DO and ND The ANOVA significar was Perfo Value of 1 the three measureme pmtected in the SI both grey. betwen t. There was biomass 120 replications of yield were measured (North and south) while the ND treatment had only one yield measurement made by the farmer due to the late harvest. At a confidence level of 95%, there was no significant difference found between the SI and D0 treatment for the 1990 corn grain yields. There was a high significant difference found between the SI treatment compared to both the D0 and ND -treatments. No significant difference was found between the D0 and ND treatments. The ANOVA tables for leaf index and plant biomass test of significant difference.are presented in Appendix H. The test was performed at a 95% confidence level, with a F critical value cf 1.31. ‘There was significant.difference found between the three treatments for all leaf index and plant biomass measurements made during both growing seasons. The Fischer Protected LSD test found significantly higher peak leaf index in the SI treatment compared to the D0 and ND leaf indexes for both growing seasons. No significant difference was found between the D0 and ND treatment leaf indexes for both growing seasons . There was significant difference found between the SI plant biomass and both the D0 and ND plant biomass for the 1990 growing season. No significant difference was found between the D0 and ND plant biomass. Plant biomass of the SI treatment was found to be significantly higher than the D0 treatment a1 biomass was the entire significant growing sea Plant bion significant the 1991 g: kernel prod Plant biom biomass f0} 121 treatment at the end of the 1990 growing season. ‘The SI plant biomass was significantly higher than the ND plant biomass for the entire 1990 growing season. The D0 plant biomass was not significantly different than the ND plant biomass for the 1990 growing season. Plant biomass from the SI treatment was found to be significantly lower than the D0 plant biomass at the end of the 1991 growing season. This may be due to the increased kernel production observed in the SI treatment. The SI and D0 plant biomass was significantly higher than the ND plant biomass for the 1991 growing season. At t seasc CONCLUSIONS At the Unionville site for the 1990 and 1991 growing seasons: 1. Subirrigation / controlled drainage increased the volume of outflow from the 'tile compared to conventional subsurface drainage for both above and below average growing season rainfall. Subirrigation / controlled drainage had practically no effect on surface drainage volume compared to conventional subsurface drainage for both above and below average growing season rainfall. Both subirrigation / controlled drainage and conventional subsurface drainage reduced surface drainage compared to the non-tiled treatment for above average growing season rainfall. The subirrigation / controlled drainage had no effect on surface drainage compared to the non-tiled treatment. for' belOW' average: growing season rainfall. The sum of tile outflow discharge and surface drainage for both subirrigation / controlled drainage and conventional subsurface drainage was greater than the surface drainage from the non- tiled treatment for both above and below average growing season rainfall. Tile drainage nitrate nitrogen loading and average monthly concentrations were reduced by subirrigation / controlled drainage for both above and below average growing season rainfall. The surface drainage nitrate nitrogen loading was increased slightly by subirrigation / controlled drainage compared to conventional subsurface drainage for above average growing season rainfall. There was no effect on surface drainage nitrate nitrogen between (subirrigation / controlled drainage and conventional subsurface drainage for below average growing season rainfall. The non-tiled treatment surface drainage nitrate nitrogen loading was reduced by both subirrigation / controlled drainage and conventional subsurface drainage for both above and below average growing season rainfall. Tile drainage orthophosphate phosphorus loading and average monthly concentrations were reduced 122 10. ll. 12. 13. 14. 15. 15. 10. 11. 12. 13. 14. 15. 16. 123 slightly by subirrigation / controlled drainage for above average growing season rainfall, but were insignificant for below average growing season rainfall. Surface drainage orthophosphate phosphorus loading was reduced slightly by subirrigation / controlled drainage compared to conventional subsurface drainage for above average growing season rainfall, but were insignificant for below average growing season rainfall. Non-tiled treatment surface:drainage orthophosphate phosphorus loading was reduced by both subirrigation / controlled drainage . and conventional subsurface drainage for above average growing season rainfall, but were insignificant for below average growing season rainfall. Tile drainage potassium loading and average monthly concentrations were increased by subirrigation / controlled drainage for both above and below average growing season rainfall. Surface drainage potassium loading was reduced slightly by subirrigation / controlled drainage compared to conventional subsurface drainage for above average growing season rainfall. There was little to no effect on surface drainage potassium for below average growing season rainfall. Non-tiled treatment surface drainage potassium loading was reduced by both subirrigation / controlled drainage and conventional drainage for above average growing season rainfall. There was little effect on non-tiled surface drainage potassium loading for below average growing season rainfall. Tile drainage ammonia nitrogen loading and average monthly concentrations were increased by subirrigation / controlled drainage for below average growing season rainfall. The surface drainage ammonia nitrogen loading was decreased by subirrigation / controlled drainage compared to conventional subsurface drainage for below average growing season rainfall. The non-tiled treatment surface drainage ammonia nitrogen loading was reduced by both-subirrigation / controlled drainage, but. increased by conventional subsurface drainage for below average 17. 18. 19. 20. 21. 22. 23. 24. 25, CO} 105 The Yie 17. 18. 19. 20. 21. 22. 23. 24. 25. 124 growing season rainfall. Combined tile and surface drainage nitrate nitrogen loading was reduced by subirrigation / controlled drainage ”compared to conventional subsurface drainage for both aboVe and below average growing season rainfall. ' Combined tile and surface drainage nitrate nitrogen and. ;potassium. loadings. for’, subirrigation ' / controlled drainage and conventional subsurface drainage were greater than the non-tiled treatment surface drainage nitrate nitrogen and potassium loadings loading for both above and below average growing season rainfall. Combined tile and surface drainage orthophosphate phosphorus loading was approximately equal for subirrigation / controlled drainage and conventional subsurface drainage for above average growing season rainfall. Combined tile and surface drainage orthophosphate phosphorus loadings for subirrigation / controlled drainage and conventional subsurface drainage were less than the non-tiled treatment surface drainage orthophosphate loading for above” average growing season rainfall. For all three treatments, nitrate nitrogen, orthophosphate phosphorus and potassium loadings in the soil at and below 0.6m remained relatively constant through out the study period. Tile drainage alachlor loadings were higher from the subirrigation / controlled drainage treatment compared to the conventional subsurface drainage treatment. - Surface drainage alachlor loadings were lower from the subirrigation / controlled drainage compared to both conventional subsurface drainage and no subsurface drainage treatments. The combined tile and surface drainage alachlor loadings were higher from the subirrigation / controlled drainage treatment than from the conventional subsurface drainage treatment, which were higher than the surface drainage alachlor loadings from the no subsurface drainage treatment. The subirrigation / controlled drainage grain yield was greater than for conventional drainage 26. 27. 28. 29. 26. 27. 28. 29. 125 which was greater than non-tiled treatment yield for both above and below average growing season rainfall. Leaf area was higher in the no subsurface drainage treatment compared to the subirrigation / controlled drainage and conventional subsurface drainage treatments for above average growing season rainfall. For below average growing season rainfall, no subsurface drainage treatment had higher leaf area compared to conventional subsurface: drainage, but lower‘ compared 'to subirrigation / controlled drainage. Stem ‘volume 'was higher in the subirrigation / controlled drainage treatment compared to the conventional subsurface drainage and no subsurface drainage, treatments for above average growing season rainfall. Stem volume was lower in the subirrigation / controlled drainage treatment compared to the conventional subsurface drainage treatment, but higher compared to the no subsurface drainage treatment for below average growing season rainfall. . Plant nutrient content increased in the subirrigation / controlled drainage treatment compared to the convectional subsurface drainage and no subsurface drainage treatments for above average growing season rainfall. For below average growing season rainfall, plant nutrient content was lower in the subirrigation / controlled drainage treatment compared to the conventional subsurface drainage and no subsurface drainage treatments. Corn kernel yield and quality was increased by the subirrigation / controlled drainage treatment compared to the conventional subsurface drainage and no subsurface drainage treatments for above and below average growing season rainfall. Through ‘a water tat nutrient as nitra‘ reduced i drainage managenen of below There are by the fa the CrOp; be made a highest F of manag, risk 0f p Climatolc perfoI‘mar Under Pr: and Subi1 redUCing increas if. addition RECOMMENDATIONS Through water table management, control and regulation of water table depth allows for better management of soil and nutrient loss associated with surface runoff. Nutrients such as nitrate nitrogen and orthophosphate phosphorus can be reduced in subsurface drainage discharge through controlled drainage practices. It has also been shown that water table management can increase crop yields especially during periods of below average growing season rainfall. There are many alternative management schemes that can be used by the farmer in water table management in order to best meet the cropping requirements for the producer. The farmer must be made aware of the critical times when drainage can.pose the highest pollution potential to receiving waters and what sort of management decisions can be implemented to minimize the risk of pollution while not seriously endangering the quality of the crop. Climatological factors had a tremendous affect on the overall performance of the different drainage practices researched. Under proper management, a well designed controlled drainage and subirrigation system has the potential of dramatically reducing accumulative plant nutrients and substantially increasing crop yield. Studies continue to show that in addition to design and management factors, site 126 characteri table man: Unmet to ‘huther differer environ: develop enviror on Sit: recomx that SYste ' 127 characteristics influence the capability of operating a water table management system without posing a serious pollution threat to receiving waters. Further research is needed to better understand the impacts different water table management schemes have on the environment. Research must continue to be directed towards developing models that are capable of providing environmentally and economically sound recommendations based on site specific characteristics. Farmers then can use these recommendations towards making critical operation decisions that will allow the operation of water table management systems with minimal environmental impacts. The research performed supports the need to classify water table management systems as a conservation practice and a best management practice. As the potential use and benefits from water table management systems is further realized by researchers and farmers, it is important that research is continued towards identifying acceptable and practical agricultural production drainage practices which are economically beneficial while not detrimental to the fragile ecology that we exist within. APPENDIX A Monitoring Equipment Diagram H9 Pressure Transducer Box Cassette lube Air Line lube Air Line Storbuck Dotalogger Model Computer Isco Voter 1990 GrowiEg Flume Stillmg veu Cor-pressed Gus Source- 1991 GPO'inQ Season Set up |_é ram—9““ Orifice Flow Me ter Rom Gauge Observation \Jeu 130 Regressions for 1990 watertable observation wells, flumes, orifice meters and rain gages — 19 lg; Iransducer No. Regression Eggation R2 g_ Orifice: 01Nd1 DO 7 y 8 112.7 + 7.41 * x 0.969 6 01Nd2 DO 8 y 8 100.7 + 7.83 * x 0.975 6 02Nd3 SI 7 y 8 138.7 + 6.49 * x 0.955 6 02Hd4 SI 8 y 8 117.5 + 6.65 * x 0.976 6 Flumes: FNd1 SI 6 y 8 23.0 + 0.75 * x 0.993 6 FNdZ SI 7 NOT OPERATING PROPERLY Fad} 00 6 y 8 39.7 + 2.12 * x 1.000 6 FNd4 DO 7 y 8 40.0 + 2.00 * x 0.876 6 FNdS N0 6 y 8 32.1 + 1.06 * x 0.990 6 Ffld6 N0 7 y 8 52.0 + 2.00 * x 0.990 6 Observation Hells: 0HANd1 SI 2 y 8 53.4 - 0.20 * x 0.939 5 OHANdZ SI 2 y 8 58.4 - 0.21 * x 0.890 5 0HAHd3 SI 2 y 8 60.1 - 0.24 * x 0.999 5 0HANd4 SI 2 y 8 56.6 - 0.22 * x 0.999 5 MIKE SI 2 NOT OPERATING PROPERLY 0HAHd6 SI 3 y 8 55.8 - 0.24 * x 0.860 5 Mfldi DO 3 NOT OPERATING PROPERLY OHBNdZ 00 3 y 8 60.4 - 0.21 * x 0.899 4 OHBNd3 00 3 y 8 71.1 - 0.61 * x 0.988 4 OHBHd4 00 3 y 8 58.6 - 0.47 * x 0.998 4 OHBNdS 00 4 y 8 54.2 - 0.17 * x 0.948 4 OHBNd6 00 4 NOT OPERATING PROPERLY OHCNd1 ND 4 y 8 55.7 - 0.21 * x 0.910 3 OHCNdZ ND 4 NOT OPERATING PROPERLY OHCNd3 NO 4 NOT OPERATING PROPERLY OHCNd4 ND 5 NOT OPERATING PROPERLY OHCNdS ND 5 y 8 70.2 - 0.26 * x 0.933 3 OHCHdé ND 5 NOT OPERATING PROPERLY Rain Gages: R61 SI 6 y 8 23.1 + 8.20 * x 0.993 6 R02 00 6 y 8 39.4 + 9.41 * x 0.912 6 RG3 NO 8 NOT OPERATING PROPERLY where: y 8 depth of water in column being measured, inches x 8 pressure transducer reading r28 correlation coefficient squared n 8 number of observations note: for observation Hells, y 8 elevation of water below ground surface level, inches 131 Regressions for 1991 watertable observation wells, flumes, orifice meters and rain gages — 10 L3 Transducer No. Regression Eggagion R’ 9_ Orifice: 0111d1 00 7 y 8 86.5 + 8.54 * x 1.000 6 0111d2 00 8 y 8 15.5 + 11.61 * x 0.985 6 0211d3 SI 7 y 8 91.5 + 10.32 * x 0.994 6 0211d4 SI 7 y 8 102.0 + 10.21 * x 0.996 6 Flunes: Fl-ld1 SI 6 y 8 12.5 + 10.46 * x 1.000 6 Flle SI 7 y 8 12.5 + 10.82 * x 1.000 6 Flch 00 6 y 8 12.5 + 10.68 * x 1.000 6 Flldlo 00 7 y 8 15.5 + 10.89 * x 0.999 6 F116 ND 6 y 8 36.5 + 9.46 * x 0.995 6 F11d6 N0 7 y 8 31.3 + 8.36* x 1.000 6 Observation Hells: WAlld1 SI 2 y 8 72.1 + -0.32 * x 0.939 6 (AlAlle SI 2 y 8 65.4 + -0.81 * x 0.890 5 0HA11d3 SI 2 y 8 66.0 + -0.16 * x 0.999 3 OHAlld4 SI 2 y 8 58.6 + -0.19 * x 0.999 7 OHAlldS SI 2 y 8 58.2 + -0.19 * x 0.817 6 0HAlld6 SI 3 y 8 63.3 + -0.37 * x 0.894 5 OHBHd1 00 3 y 8 61.1 + -0.18 * x 0.994 8 01181le 00 3 y 8 55.3 + -0.16 * x 0.899 6 0.1811113 00 3 y 8 54.7 + -0.11 * x 0.988 6 OHBNd4 00 3 y 8 58.5 + -0.16 * x 0.998 6 OHBHdS 00 4 y 8 54.0 + -0.15 * x 0.948 6 ONBHdb 00 4 NOT OPERATING PROPERLY Mlidi NO 4 NOT OPERATING PROPERLY OHCNdZ N0 4 y 8 55.8 + -0.11 * x 0.930 3 0HClld3 N0 4 y 8 54.8 + -0.82 * x 0.830 3 OHCNd4 N0 5 y 8 60.2 + -0.21 * x 0.986 3 OHGNdS ND 5 y 8 65.4 + -0.20 * x 0.933 3 WCNdé N0 5 NOT OPERATING PROPERLY Rain Gages: RG1 SI 6 y 8 16.0 + 9.50 * x 0.997 4 RG2 00 6 y 8 33.0 + 9.00 * x 0.998 4 RG3 NO 6 NOT OPERATING PROPERLY where: y 8 depth of water in colum being measured, inches x 8 pressure transducer reading r28 correlation coefficient squared n 8 nmber of observations note: for observation wells, y 8 elevation of water below ground surface, inches APPENDIX B Climatological Data 1990 DATE 31 0C 30 0C 29 OC' 28 OC‘ 27 0C7 26 0C1 25 0C1 24 0C? 23 0C1 22 OCT 21 OCT 20 OCT 19 OCT 18 OCT 17 OCT 16 OCT 15 OCT 14 OCT 13 OCT 12 OCT 11 OCT 10 OCT 09 OCT 08 OCT 07 OCT 06 OCT 05 OCT 04 OCT 03 OCT 02 OCT 3° SEP 27 SEp 26 SEP 25 SEP 24 SEP 23 SEP 22 SEP 21 SEP 2° SEP 133 1990 UNIONVILLE WEATHER DATA DATE AIR TEMP AIR TEMP AIR TEMP GRD TEMP RAIN SOLAR MAX MIN AVG C C C C m MJ 31 OCT 90 16.01 -1.13 6.93 39.78 0 8.38 30 OCT 90 14.94 .9057 7.22 39.11 0 8.577 29 OCT 90 10.64 -4.52 3.08 38.49 0 11.94 28 OCT 90 6.22 2.363 3.816 38.52 0 3.52 27 OCT 90 15.77 -.338 7.32 37.08 0 9.146 26 OCT 90 7.949 -3.71 2.48 37.08 0 11.55 25 OCT 90 8.656 2.73 4.47 40.08 0 7.71 24 OCT 90 11.31 .841 5.85 40.19 0 5.85 23 OCT 90 13.03 -2.747 4.866 39.46 0 11.82 22 OCT 90 13.31 1.99 7.92 40.51 0 9.41 21 OCT 90 15.88 5.806 10.31 38.65 0 4.73 20 OCT 90 16.61 -.235 7.01 37.92 0 12.75 19 OCT 90 9.69 .745 4.37 30.94 0 9.14 18 OCT 90 19.46 3.88 9.91 12.61 5 2.75 17 OCT 90 25.26 10.38 17.37 11.54 7 11.55 16 OCT 90 18.34 1.83 9.42 10.48 0 13.24 15 OCT 90 14.7 4.979 10.11 10.94 0 13.72 14 OCT 90 19.65 3.45 10.41 10.32 12 9.758 13 OCT 90 14.7 -.2355 6.05 10.03 0 11.26 12 OCT 90 13.06 .8798 6.35 10.4 0 9.06 11 OCT 90 14.45 4.488 8.4 10.59 0 13.25 10 OCT 90 12.57 6.477 8.11 10.63 44 1.09 09 OCT 90 7.83 6.24 7 11.38 20 2.09 08 OCT 90 12.7 6.1 8.47 12.82 5 5.66 07 OCT 90 14.37 8.72 10.89 14.38 3 2.97 06 OCT 90 26.79 13.21 19.76 14.52 0 15.27 05 OCT 90 24.28 9.59 16.08 13.26 0 15.48 04 OCT 90 19.59 9.275 13.53 13.92 15 12.88 03 OCT 90 22 6.64 14.7 12.62 15 6.66 02 OCT 90 21 3.477 11.7 12.27 0 16.64 01 OCT 90 15.97 2.55 8.475 12.65 1 5.68 30 SEP 90 13.92 4.86 10.33 14.02 3 7.54 29 SEP 90 18.81 11.55 13.36 14.41 0 10.99 28 SEP 90 19.54 8.93 13.45 14.25 0 12.09 27 SEP 90 25.6 6.2 14.6 13.62 0 16.89 26 SEP 90 17.03 8.39 13.06 13.69 0 6.77 25 SEP 90 21.49 9.49 14.51 12.76 0 14.84 24 SEP 90 18.95 2.01 9.94 12.08 0 14.02 23 SEP 90 11.22 6.798 8.306 13.09 1 7.09 22 SEP 90 16.92 8.121 12.27 14.22 0 12.82 21 SEP 90 14.79 9.22 12.62 14.68 7 2.265 20 SEP 90 22.88 10.09 12.5 14.3 0 19.07 19 18 17 16 15 14 13 12 11 10 O9 08 O7 06 05 04 03 02 01 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 09 08 07 06 05 04 03 mmmm mmmmmmm mmmmmmm {D'wtvib'th'm >r>>3r3fi vtlrfitfitb'r wywzxauzu Pkkkkrl 19 18 17 16 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 09 08 07 06 05 04 03 SEP SEP SEP SEP SEP SEP SEP SEP SEP SEP SEP SEP SEP SEP SEP SEP SEP SEP SEP AUG AUG AUG AUG AUG AUG AUG AUG AUG AUG AUG AUG AUG AUG AUG AUG AUG AUG AUG AUG AUG AUG AUG AUG AUG AUG AUG AUG AUG 90 90 90 90 90 90 90 90 90 90 90 9O 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 9O 90 90 90 90 90 90 90 90 90 90 90 15.53 19.03 15.97 13.87 24.82 28.36 29.05 23.77 28.24 27.1 24.97 20.54 24.08 26.34 28.34 23.56 26.38 28.98 28.45 26.06 26.1 30.94 31.29 29.63 28.62 28.6 24.7 22.17 21.22 19.3 18.48 28.98 27.65 29.14 26.91 24.96 21 24.07 24.91 28.1 28.41 26.61 23.32 17.66 22.86 20.54 28.5 5.506 .623 7.751 10.07 12.69 15.71 12.08 9.238 16.45 12.8 6.533 10.56 16.37 17.14 11.84 10.99 12.77 15.5 11.21 10.36 12.66 17.3 18.44 16.86 16.37 14 17.62 15.27 16.16 14.18 14.35 18.31 16.11 17.81 14.4 9.383 11.98 13.98 15.16 13.11 11.92 9.572 11.41 14.95 15.9 17.84 11.89 134 12.5 9.23 11.86 11.76 18.5 21.43 19.34 16.78 20.82 18.74 15.16 17.03 19.53 22.15 19.63 16.31 19.38 21.81 19.63 18.12 19.36 23.72 24.8 21.96 22.21 21.09 19.94 18.39 17.91 16.47 16.14 22.43 21.47 22.44 19.77 17.08 17.92 18.36 20.01 20.9 20.31 17.85 17.34 15.9 19.71 19.35 20.46 16.15 17.25 19.14 18.98 18.3 18.7 18.89 18.12 17.78 19.34 19.78 19.73 18.63 19.11 19.85 19.57 19.28 19.54 20.64 21.17 20.49 19.95 19.52 18.85 18.5 18.11 17.97 17.98 19.42 19.96 19.58 19.09 18.03 17.74 18.72 18.78 19.1 18.83 18.31 17.89 17.86 18.61 19.46 19.68 19.5 OU'IONOOOOOUOOHOOHNOOOOOOHhI—‘OOOOOOOO\lmOOOOOONl-‘N O 0‘ 00 PM N U 17.3 5.22 5.38 14.27 18.53 18.51 16.52 17.79 21.7 5.764 3.492 18.99 15.67 20.36 22.48 17.13 18.4 22.97 20.61 15.01 20.89 14.76 20.63 22.17 7.653 9.233 6.408 6.017 3.699 16.11 14.97 17.29 14.02 25.46 11.12 10.25 20.55 25.25 25.84 24.73 24.42 7.679 10.52 2.506 20.23 02 01 31 30 29 28 27 26 25 24 23 22 N y... Baaaqqqqqqqqqquv 20 19 18 17 16 J! 15 J1 14 J! 13 J1 12 J! 11 J1 10 J[ 09 .n 08 J[ 07 J1 06 JL‘ 05 J[ 04 JL‘ 02 01 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 09 08 07 O6 05 04 02 01 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 U U Z§§§§§§§§§§§§§§ZZ U 5 JUL JUL 8 JUL JUL JUL JUL JUL JUL JUL 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 28.78 26.93 22.38 25.77 29.73 31.57 30.31 29.22 27.98 27.02 25.54 21 27.1 25.05 29.96 28.62 29.67 26.77 26.72 18.3 24.34 22.67 25.5 26.79 29.12 32.42 25.78 22.22 29.69 34.97 31.92 23.21 28.93 28.13 23.35 26.72 26.19 28.08 23.06 17.01 21.13 28.9 25.39 23.99 27.28 33.64 28.38 10.61 7.872 10.75 18.12 16.45 17.36 13.21 13 12.57 11.1 10.67 12.97 14.33 17.44 15.59 16.8 17.08 14.12 16.07 14.83 12.08 14.52 14.28 14.52 17.02 15.16 6.734 11.3 15.4 21.3 -112.5 14.88 15.51 16.76 13.52 13.11 15.96 7.934 12.87 13.55 14.87 16.36 12.07 11.8 13.38 19.15 15.11 135 20.11 17.87 17.65 21.44 23.51 24.08 21.68 21.11 20.62 19.21 17.65 17.36 20.14 20.88 21.87 20.43 23.19 20.28 19.87 16.42 17.79 17.84 18.41 20.35 23.19 22.47 17.35 17.73 20.45 27.73 20.14 18.7 21.28 21.98 18.28 18.74 20.29 18.95 17.18 15.24 17.94 22.08 18.59 16.81 22.58 26.1 21.57 18.93 18.45 19.61 21.31 21.31 20.82 20.06 19.9 19.58 19.07 18.78 19.76 20.31 20.63 20.17 20.91 20.67 19.64 19.55 20.12 21.02 21.34 22.19 22.63 22.08 21.39 21.74 22.77 23.89 23 21.01 20.61 20.42 19.9 19.89 19.21 19.13 18.06 16.85 17.74 20.12 20.31 20.4 20.47 21.89 21.43 21.24 OOOOO‘OOOOOUSOOMONONOOOOOOOQOOO OOOOOOHODOOHOOHWOO 27.15 27.91 23.13 12.7 15.86 22.63 21.89 24.76 28.1 28.43 21.36 9.974 23.49 16.46 22.09 10.6 22.79 23.81 16.16 4.194 24.55 29.21 15.68 29.18 27.18 14.52 23.38 30.56 23.97 26.82 5.87 25.84 23.03 21.34 12.8 27.5 14.89 28.46 29.18 3.391 4.721 28.15 11.1 28.85 20.62 18.32 21.22 15 14 13 12 11 10 09 08 O7 06 05 04 03 02 01 31 30 29 28 27 26 25 24 MA 5229999999906 Efifififififififi 15 14 13 12 11 10 O9 08 07 06 05 O4 03 02 01 31 30 29 28 27 26 25 24 10 09 08 07 06 05 04 03 02 01 MAY MAY MAY MAY MAY MAY MAY MAY 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 27.99 29.42 33.48 20.34 23.41 23.07 26.9 25.13 25.97 26.05 21.73 18.1 25.18 30.05 27.98 24.86 20.82 12.86 23.99 22.6 19.18 23.63 19.32 19.04 19.67 29.11 24.65 16.31 16.84 9.747 17.79 16.29 14.95 16.73 18.06 17.24 12.43 13.5 14 16.34 14.13 10.26 13.64 4.072 6.151 8.72 18.92 9.87 5.553 6.02 6.392 7.392 7.872 11.44 8.262 10.62 1.706 8.169 7.695 5.938 6.262 5.58 5.539 2.389 .9447 6.636 136 22.04 23.88 24.67 16.49 18.52 18.17 20.72 19.07 19.29 19.51 14.11 11.42 17.52 23.75 19.79 16.67 13.69 9.737 16.4 15.8 14.48 15.72 14.26 8.915 14.83 19.24 15.35 9.888 10 7.154 10.29 8.156 10.49 20.62 20.39 18.02 18.16 19.18 18.8 19.13 18.87 17.9 16.34 15.86 15.87 17.81 18.12 16.37 15.37 14.15 14.8 15.19 14.04 14.06 13.67 13.35 12.54 13.81 12.62 10.79 10.34 9.598 10.67 11.31 11.8 13.51 uOOOOOOOOO—‘OOOOOOOOONOOO OOOHO‘OOODU 30.16 18.04 23.75 6.113 27.77 23.78 23.88 19.29 30.22 25.58 20.9 25.14 20.42 18.24 26.38 30.7 30.79 28.74 26.98 29.12 12.5 24.4 24.59 8.928 16 26.62 27.28 24.42 23.27 1.788 17.78 27.38 26.7 1993 DATI 137 1991 UNIONVILLE WEATHER DATA DATE AIR TEMP AIR TEMP AIR TEMP GRD TEMP RAIN SOLAR MAX MIN AVG deg C deg C deg C deg C mm MJ 06 OCT 91 6.64 1.56 4.32 7.98 .00 5.41 05 OCT 91 6.55 2.10 4.76 8.79 .00 3.21 04 OCT 91 8.91 —.87 3.72 9.55 .00 17.87 03 OCT 91 3.33 -7.21 2.56 9.76 39.00 4.21 02 OCT 91 5.54 -5.65 3.01 10.00 4.00 5.67 01 OCT 91 10.65 -3.22 6.78 10.05 .00 7.77 29 SEP 91 11.89 -2.47 5.55 11.42 .00 20.04 28 SEP 91 17.12 -3.13 5.78 11.56 .00 20.93 27 SEP 91 13.00 2.68 6.89 10.65 .00 14.40 26 SEP 91 12.50 5.65 8.29 10.01 .00 11.60 25 SEP 91 13.93 -1.51 6.34 9.01 3.00 6.10 24 SEP 91 11.26 -.42 6.29 9.66 .00 6.60 23 SEP 91 17.78 7.90 12.62 9.54 5.00 19.42 22 SEP 91 20.14 4.62 12.75 9.80 .00 9.49 21 SEP 91 18.39 1.54 10.24 11.21 .00 21.98 20 SEP 91 14.33 6.75 9.90 16.43 .00 12.96 19 SEP 91 17.83 8.00 11.31 17.65 .00 17.57 18 SEP 91 19.17 9.92 14.04 19.56 3.00 10.83 17 SEP 91 24.05 12.08 17.54 22.34 .00 22.93 16 SEP 91 27.94 17.17 22.58 25.79 4.00 14.95 15 SEP 91 32.64 19.91 25.14 24.69 .00 18.64 14 SEP 91 25.11 11.35 18.23 25.10 1.00 10.64 13 SEP 91 22.26 13.89 17.86 25.00 .00 6.62 12 SEP 91 24.47 6.20 15.54 24.58 .00 23.50 11 SEP 91 21.80 11.08 15.99 24.68 .00 19.30 10 SEP 91 25.99 15.17 21.28 25.67 3.00 16.06 09 SEP 91 31.27 19.12 23.66 25.74 .00 19.22 08 SEP 91 29.69 14.19 21.08 25.64 .00 17.51 07 SEP 91 28.23 11.84 19.47 25.39 .00 12.46 06 SEP 91 28.58 10.56 19.42 25.33 .00 25.64 05 SEP 91 28.28 6.90 17.29 24.90 .00 25.39 04 SEP 91 26.15 11.22 19.16 25.30 .00 27.50 03 SEP 91 25.58 10.12 19.09 25.12 3.00 6.68 02 SEP 91 25.22 4.35 15.70 24.63 .00 27.65 01 SEP 91 23.60 4.80 14.56 24.42 .00 28.11 31 AUG 91 23.88 9.79 18.80 25.12 .00 21.25 30 AUG 91 33.08 19.25 25.21 26.21 .00 16.76 29 AUG 91 35.52 16.80 25.39 26.36 .00 22.70 28 AL“: 91 34.37 16.20 24.90 26.35 .00 25.80 27 AUG 91 33.71 16.31 24.40 26.38 .00 25.10 26 AUG 91 32.82 16.02 23.84 26.38 .00 24.17 25 AUG 91 31.06 11.93 21.09 25.81 .00 27.71 24 AUG 91 23 AUG 91 22 AUG 91 20 AUG 91 19 AUG 91 18 AUG 91 17 AUG 91 16 AUG 91 15 AUG 91 14 AUG 91 13 AUG 91 12 AUG 91 11 AUG 91 10 AUG 91 9 AUG 91 8 AUG 91 7 AUG 91 6 AUG 91 5 AUG 91 4 AUG 91 3 AUG 91 2 AUG 91 1 AUG 91 31 JUL 91 29 JUL 91 27.49 23.35 29.37 23.60 22.23 25.46 24.99 29.76 33.08 29.78 30.62 28.43 28.37 26.84 24.84 19.66 25.69 24.13 22.70 23.95 23.55 24.25 32.44 30.66 26.91 20.48 26.19 26.30 23.81 25.80 28.82 28.03 29.98 27.16 35.43 34.91 34.29 31.15 30.83 28.81 26.12 23.99 22.67 27.06 28.86 25.52 26.20 32.62 15.78 12.76 14.34 11.18 15.64 13.62 15.25 17.34 14.43 13.18 11.49 9.63 11.10 14.33 14.74 12.25 12.86 7.04 10.67 12.83 16.80 16.60 15.79 10.66 15.36 14.08 11.10 8.62 10.93 15.38 13.21 19.43 19.28 20.53 19.24 20.10 16.97 17.63 13.43 10.30 14.08 15.09 10.49 12.59 12.98 13.53 14.47 18.93 138 20.30 18.38 21.09 18.42 18.10 19.48 20.18 22.25 21.59 21.11 20.80 19.01 19.77 20.12 19.74 16.09 18.89 16.11 17.02 18.28 19.30 19.83 24.26 21.35 20.26 17.50 17.81 17.84 18.05 19.52 21.85 24.23 23.66 23.81 27.40 26.72 25.86 23.77 22.51 20.43 20.78 18.61 16.60 20.31 21.18 19.09 21.07 25.09 25.65 25.28 25.78 20.50 21.20 21.20 22.70 21.60 21.10 20.50 20.50 20.50 20.50 20.50 20.80 21.80 20.50 20.50 20.60 21.10 21.80 22.60 20.50 20.50 20.50 20.50 20.50 20.50 20.60 20.50 20.50 20.50 20.90 23.20 20.50 20.50 20.50 20.50 20.50 20.50 20.50 20.70 20.60 20.50 20.50 20.50 21.20 23.70 .00 .00 .00 .00 15.00 .00 .00 10.00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 30.00 .00 .00 .00 .00 1.00 .00 .00 .00 .00 .00 .00 .00 10.00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 5.00 24.96 29.01 24.22 21.00 8.27 15.10 6.41 17.97 18.75 18.29 23.88 21.88 25.88 24.93 24.26 6.90 24.39 25.83 26.90 16.28 12.58 7.07 27.43 26.21 23.92 6.30 15.88 27.92 28.51 24.38 27.69 28.68 13.36 8.00 22.89 26.14 26.64 21.89 27.64 29.63 29.77 18.83 5.64 29.65 27.01 28.89 27.46 25.85 gaéaaagagaaéaggaaéfigégg 39' 31 MAY 24 MAY 23 MAY 22 MAY 21 MAY 20 MAY 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 31.91 28.15 27.46 32.78 28.07 28.55 21.74 33.15 32.17 32.22 32.04 27.79 27.64 24.09 16.70 26.11 29.83 31.21 28.78 26.07 26.27 30.31 32.04 23.51 23.07 26.00 30.25 29.66 29.14 26.82 24.26 21.54 18.21 24.13 24.20 23.66 28.78 29.57 30.34 31.91 29.38 27.16 26.36 30.88 29.83 31.24 27.23 20.28 15.63 16.75 18.01 17.14 17.46 12.47 13.62 19.43 20.75 21.98 15.34 12.21 8.36 11.15 12.98 15.10 15.74 16.43 14.89 17.41 19.64 19.10 11.34 7.75 11.48 18.46 19.16 13.40 12.73 10.46 10.00 10.70 10.63 11.31 13.99 15.74 19.25 19.51 19.45 16.78 19.96 17.98 16.80 19.81 17.91 14.26 8.61 4.99 139 24.30 22.16 22.12 22.70 22.32 20.48 18.07 26.10 26.55 26.70 24.62 20.83 18.33 17.33 14.80 19.55 23.62 24.21 22.28 21.30 22.08 22.84 22.05 16.13 18.94 21.31 24.11 22.47 20.76 19.27 17.63 16.83 14.61 16.69 18.54 19.74 22.94 24.20 23.74 23.18 23.98 22.40 20.44 23.30 23.68 23.06 18.70 13.72 20.60 21.40 21.60 23.20 20.50 20.50 20.50 20.50 20.50 22.10 21.90 21.20 20.60 20.50 20.10 21.10 21.90 22.00 21.60 21.40 21.60 21.70 21.60 20.40 20.90 21.40 22.00 21.60 21.30 21.00 20.30 19.14 20.26 20.61 20.72 . 20.77 20.86 20.84 21.13 20.94 20.43 19.63 19.47 19.48 19.45 19.40 15.00 13.00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 1.00 .00 .00 .00 .00 7.00 .00 .00 .00 .00 .00 .00 5.00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 4.00 .00 .00 2.00 4.00 .00 .00 .00 .00 24.65 25.24 17.40 21.94 25.67 19.30 19.85 24.21 26.31 24.02 28.05 27.41 30.34 31.20 6.11 27.52 29.76 29.54 30.47 30.16 18.74 21.60 27.00 30.71 28.29 17.44 17.42 28.50 29.70 30.32 30.03 30.30 28.90 27.28 16.49 26.51 24.87 22.72 25.83 25.09 27.20 12.06 15.05 15.92 20.02 21.29 25.07 28.64 HHHHHHHHHH ouuubmmqmo HNUubU'lQOW 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 APR APR APR APR APR APR APR APR APR APR APR APR APR APR 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 91 18.03 14.50 20.13 31.54 28.95 30.00 29.86 30.58 28.08 21.10 17.54 11.43 11.93 13.14 17.47 11.11 10.04 10.25 14.50 18.99 22.57 18.61 23.99 21.87 19.41 13.80 15.51 15.11 5.64 3.03 7.84 12.19 9.57 12.82 18.27 9.65 5.40 5.06 5.79 14.46 12.83 16.32 14.87 17.62 11.37 8.96 5.92 4.65 5.51 6.14 1.83 2.54 4.41 5.81 7.83 11.60 10.69 12.84 9.09 8.49 3.78 5.18 .58 4.46 2.02 1.27 2.45 .40 4.36 4.97 5.71 2.67 140 11.08 8.71 10.89 23.62 21.51 21.67 20.91 22.74 20.22 15.60 10.17 8.03 8.06 8.59 9.16 5.37 6.26 8.05 10.47 15.52 16.89 15.00 16.23 14.12 11.64 8.38 8.30 8.88 3.47 2.15 4.84 6.34 6.86 8.67 9.76 6.13 12.00 12.00 13.00 19.38 19.32 19.26 17.99 17.69 17.56 10.35 9.20 8.56 9.12 9.99 7.69 6.00 9.43 11.50 13.72 15.68 13.11 12.01 10.27 8.10 7.21 7.16 7.13 7.10 7.02 7.04 7.09 7.13 7.13 7.11 8.27 7.04 .00 .00 .00 2.00 .00 .00 4.00 .00 .00 .00 4.00 .00 .00 .00 6.00 .00 .00 .00 .00 175.00 .00 .00 15.00 9.00 .00 .00 4.00 2.00 .00 .00 .00 .00 .00 .00 .00 11.00 4.00 29.90 23.77 4.71 23.18 27.12 27.27 25.45 22.05 24.21 25.68 17.05 18.47 11.82 3.84 14.45 16.97 12.29 8.87 9.36 19.31 12.95 8.88 18.16 20.17 23.53 17.81 12.23 25.78 4.61 3.88 4.07 19.41 19.02 23.54 6.55 3.22 APPENDIX C Observation Well Watertable Elevation . r...” - -231... .. .... u if... .. 2:92:93... 1. .1... tin-incl... 142 W S 5 I1 I1 1» in I. i-- i« u u an. - u m w 0.0—r num- “In. a— u A... ham—r our luau-v tfl mo 1990 SI-South: 1» from tile CHAIM“ 1990 Sl-North: 110 from tile Mud. l h b- M A"! w h “I. 1“ 1990 SI-South: 1.650! from tile OUAHdZ “maul;- - 835 “£28; I 11mm: :wmw 1990 Sl-South: 2.3. from tile (”AW 1990 SI-North: 2.30: from tile OUAHdb ‘14 i 314. “d ”d II< U WI*. :4. a. wam IUI 1991 Sl-South: 1m from tile OUAHd1 1991 Sl-South: 1.65m from tile OHAMdZ 1991 SI-South: 2.3m from tile OHAHdB A“ M & bu!- 1m 1991 Sl-North: 11!: from tile OUAHdlo u a—n unnu- an.- I...- an 1991 Sl-North: 1.65m from tile WAHdS A" III won-W 1991 Sl-North: 2.30: from tile OUAHd6 ”I“. f:;: E C ’44 / I. b- M a... W H "I. mo 1990 DO-North: 101 from tile OHBHdl. - u a." up... M-t- but: mo 1990 DO-South: 1.650: from tile Mud}! 1990 DO-North: 1.65m from tile OHBHdS J'- M A” w an. m I“ 1990-South: 2.3m from tile OHBHd3 ww. $4.113 H- 23.3.3 6. -4. . uuuuuumu w it QMUUhlL it: h - u A” hrs-— on— but. A... swu— a—n— Inn-n- 1.1 In 1991 DO-South: 10: from tile OHBHd‘l 1991 DO-North: 1m from tile OHBHdlo I. - M A." w 0“- u-m- A... M on— than. I” lul 1991 Do-South: 1.65m from tile OHBHdZ 1991 DO-North: 1.65m from tile ouauds 1991-South: 2.301 from tile OHBHd3 h. 146 M ww*m I” 1990 DUO-Southeast OHCHd1 1990 ND-Hest OHCHdS mun w syn—- o‘— I...- IHI 1991 DID-Southwest 0HCHd4 no in ‘10 :Im in. m I‘“ E‘ 1 1 II J u '11 111711 r1 1 'Alllll' ‘ l. L4 wand-"- 35'. M S; u u u g u u u u u 1 "In - M, ’49-! wad- nano- but. “In, Juv- .u, 2...: 3......- nuau I...- I" 'm 1991 ND-East OUCHdZ 1991 ND'HeSt WCHdS no i am I: m: I.- u u ‘ u L. i u ‘l u u no u as In, .4.- “ A... 3.4.... can. I... 1.1 1991 DID-Northeast 0HCHd3 APPENDIX D Water Sample Nutrient Analysis Data 149 UNIONVILLE WATERTABLE MANAGEMENT WATER SAMPLE NUTRIENT RESULTS TFA} = TILE FLOW SAMPLES FROM ZONE A (SI) TF8! = TILE FLOW SAMPLES FROM ZONE 8 (DO) FAI = SURFACE FLOW SAMPLES FROM FLUME 1 OF ZONE A FA2 = SURFACE FLOW SAMPLES FROM FLUME 2 OF ZONE A F81 = SURFACE FLOW SAMPLES FROM FLUME 1 OF ZONE 8 F82 = SURFACE FLOW SAMPLES FROM FLUME 2 OF ZONE 8 FCl = SURFACE FLOW SAMPLES FROM FLUME 1 OF ZONE C FCZ = SURFACE FLOW SAMPLES FROM FLUME 2 OF ZONE C TMT DATE NO3-N NH4-N P K --------------------------- ppm-------------- TFA 11/14/89 17.64 .07 5 TFA 11/14/89 21.05 .05 6 TF8 11/14/89 12.68 .06 6 TF8 11/14/89 15.06 .06 18 TFA 11/23/89 9.25 .07 6 TFA 11/23/89 9.86 .06 15 TF8 11/23/89 22.97 .05 6 TF8 11/23/89 19.55 .05 5 TFA 4/16/90 8.71 .09 14.7 TFA 4/16/90 8.24 .08 14.7 TFA 4/16/90 8.71 .09 14.7 TFA 4/16/90 8.24 .08 14.7 TF8 4/16/90 24.93 .07 6.3 TF8 4/16/90 23.61 .1 5.8 TF8 4/16/90 24.93 .07 6.3 TF8 4/16/90 23.61 .1 5.8 TFA 5/11/90 15.54 .1 22.6 TFA 5/11/90 11.15 .08 15.8 TFA 5/11/90 15.54 .1 22.6 TFA 5/11/90 11.15 .08 15.8 TF8 5/11/90 16.03 .07 3.7 TF8 5/11/90 15.89 .09 4.2 TF8 5/11/90 16.03 .07 3.7 TF8 5/11/90 15.89 .09 4.2 TFA 5/14/90 10.95 .09 15.3 TFA 5/14/90 9.37 .09 13.2 TFA 5/14/90 10.95 .09 15.3 TFA 5/14/90 9.37 .09 13.2 TF8 5/14/90 17.17 .08 4.2 TF8 5/14/90 15.95 .1 4.2 TF8 5/14/90 17.17 .08 4.2 TF8 5/14/90 15.95 .1 4.2 F81 5/22/90 2.06 .04 2.6 TFA 5/24/90 9.4 .05 8.4 TFA 5/24/90 11.41 .05 9.5 TFA 5/24/90 9.4 .05 8.4 TFA TFB TFB TFB TFB TFA TFA TFA TFA TFB TFB TFB TFB RAIN TFA TFA TFB TFB F31 F242 RAIN TFA TFA TFA TFA TFB TFB TFB TFB FAl FAZ FBI TFA TFA TFA TFA TF3 TF3 TFA TFA TFA TFA TF3 TF3 TF3 TF3 F51 FAz TFA TFB TFB TFB TFB TFA TFA TFA TFA TFB TFB TFB TFB RAIN TFA TFA TFB TFB FAl FA2 RAIN TFA TFA TFA TFA TFB TFB TFB TFB FAl FA2 F81 TFA TFA TFA TFA TFB TFB TFA TFA TFA TFA TFB TFB TFB TFB FA1 FA2 5/24/90 5/24/90 5/24/90 5/24/90 5/24/90 6/ 1/90 6/ 1/90 6/ 1/90 6/ 1/90 6/ 1/90 6/ 1/90 6/ 1/90 6/ 1/90 6/12/90 6/19/90 6/19/90 6/19/90 6/19/90 6/25/90 6/25/90 6/25/90 6/25/90 6/25/90 6/25/90 6/25/90 6/25/90 6/25/90 6/25/90 6/25/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 7/13/90 7/13/90 7/13/90 7/13/90 7/13/90 7/13/90 7/13/90 7/13/90 7/17/90 7/17/90 11.41 20.8 21.99 20.8 21.99 14.58 14.65 14.58 14.65 19.41 22.2 19.41 22.2 6.07 17.01 17.01 10.41 10.41 20.5 8.73 4.13 10.42 10.36 10.42 10.36 16.65 17.11 16.65 17.11 30.08 20.94 2.66 9.34 4.23 9.34 4.23 10.69 10.69 0 0 0 0 9.75 9.65 9.75 9.65 9.25 9.46 150 .05 .1 .09 .1 .09 .04 .04 .19 .19 .19 .07 .07 .06 .06 .02 .13 .03 .02 .03 .02 .01 .01 .1 .12 .11 .13 .11 .13 .11 .08 .08 .08 .08 .1 .1 .16 .16 3010101010 UUUUU‘ P‘th c>o<3 £00000. \OkOh-bP-‘UQU" U1 \ODWDQQO o oooooopp quwquuuuwuuumummo- 00.5 asuuasunuuuuuummmmmpwmmmmmoomoowmpoooohbpmhmb F81 FCl F C2 RAIN TFA TFA TFB TF8 TFB TFB TFB TFB TFA TFA TFA TFA TFA TFA FAl FBI F82 F C1 FC2 RAIN TFA TFA TFA TFA TFA TFA TFB (c TFB(( FC1 FC2 TFA ( c TFA ( c TF3 TF3 TF3 TF3 TF3 TF3 TFA TFA TFA TFA TFA TFA F81 FC1 FC2 RAIN TFA TFA TF8 TF8 TFB TF8 TF8 TF8 TFA TFA TFA TFA TFA TFA FA1 F81 F82 FC1 FC2 RAIN TFA TFA TFA TFA TFA TFA TFB(GRAB) TF8(GRA8) FC1 FC2 TFA(GRA8) TFA(GRA8) TF8 TF8 TF8 TF8 TF8 TFB TFA TFA TFA TFA TFA TFA 7/17/90 7/17/90 7/17/90 7/17/90 7/17/90 7/17/90 7/17/90 7/17/90 7/17/90 7/17/90 7/17/90 7/17/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/19/90 7/19/90 7/19/90 7/19/90 7/19/90 7/19/90 7/19/90 7/19/90 7/19/90 7/19/90 7/19/90 7/19/90 7/19/90 7/19/90 7/23/90 7/23/90 7/23/90 7/23/90 7/23/90 7/23/90 7/23/90 7/23/90 7/23/90 7/23/90 7/25/90 7/25/90 7/25/90 7/25/90 7/25/90 7/25/90 5.77 4.38 3.26 1.06 .14 .14 7.92 9.05 8.19 7.92 9.05 8.19 .21 1.48 .44 .21 1.48 .44 4.53 3.01 5.52 2.74 1.91 .61 1.34 .22 .32 1.34 .22 .32 35.94 35.94 8.55 .48 .21 .21 56.18 51.76 64.84 56.18 51.76 64.84 .92 1.01 2.41 .92 1.01 2.41 151 .16 .09 .19 .21 .1 .1 .14 .16 .17 .14 .16 .17 .07 .08 .1 .07 .08 .1 .09 .09 .1 .09 .1 .1 .09 .09 .08 .09 .09 .08 .08 .08 .1 .1 .07 .07 .09 .1 .1 .09 .1 .1 .08 .08 .07 .08 .08 .07 .OOCOOOCCCOOCOOOOCCOOO NQNNQthmehHI-‘HWWOO‘O‘NmmNNmNQNNNNNNNNNwUNwUN‘NNfiH .3:-uuhuuooasqmmquwbqqmmuwwuubpupuuuuuuuuuuwuuuuummm TF B TFB TF B TF B TFB TFB RAD TFA TFA TFA TFA TFA TFA TFB TFB TFB TFB TFB TFB FA1 FBI F82 FC1 FC2 RAI] TFA TFA TFA TFA TFA TFA TFB TFB TFB TF3 TF3 TFA TFA TFA TFA TFA TFA TFA TFA TFA TFA TFB TFB TFB TFB TFB TFB IRRIG. RAIN TFA TFA TFA TFA TFA TFA TFB TFB TFB TFB TFB TFB FA1 F81 F32 FC1 FC2 RAIN TFA TFA TFA TFA TFA TFA TFB TFB TFB TFB TFB TFB TFA TFA TFA TFA TFA TFA TFA TFA TFA TFA 7/25/90 7/25/90 7/25/90 7/25/90 7/25/90 7/25/90 8/ 8/ 8/ 8/ 8/ 8/ 8/ 8/ 8/ 2/90 2/90 2/90 2/90 2/90 2/90 2/90 2/90 2/90 2/90 2/90 2/90 2/90 2/90 6/90 6/90 6/90 6/90 6/90 6/90 6/90 6/90 6/90 6/90 6/90 6/90 6/90 6/90 6/90 6/90 6/90 6/90 8/90 8/90 8/90 8/90 8/90 8/90 8/10/90 8/10/90 8/10/90 8/10/90 18.89 35.37 35.4 18.89 35.37 35.4 3.05 2.88 1.93 3.05 2.88 1.93 31.05 58.93 58.78 31.05 58.93 58.78 8.87 .74 1.56 .64 .65 .55 1.11 .82 .81 1.11 .82 .81 60.51 43.71 38.74 60.51 43.71 38.74 17.22 14.07 9.61 17.22 14.07 9.61 10.27 10.9 10.29 10.27 152 .08 .08 .08 .08 .08 .08 .1 .27 .08 .07 .05 .08 .07 .05 .09 .08 .08 .09 .08 .08 .35 .32 .35 .35 .33 .35 .01 .08 .35 .01 .08 .35 .33 .35 .33 .33 .35 .33 .35 .34 .35 .35 .34 .35 .34 .35 .34 .34 \O scooooooooo UHNNHNNHUh)HmmwwNwUNmUwaNmO‘Q‘lO‘QQO‘ 01m h-mtaxo U'UUIU'lI-‘UUHUWHNNNUU‘IO‘O‘UO‘O‘Uubm-bbUIbt-‘NUUNUUN 5.31 5.88 5.31 6.50 8.81 10.50 6.50 8.81 10.50 6.50 6.50 10.00 6.50 TFA TFA TF8 TF8 TFB TFB TF B TFB RAIN TFA TFA TFA TFA TFA TFA TFB TFB TFB T? B TF8 TFB TFA TFA TFA TFA TFA TFA TFB TFB TFB TF B TFB TF8 FA1 FBl FC1 FC2 RAIN P41 F32 FC1 FC2 TFA TFA TFA TFA TFA TFA TFA TFB TFB TFB TFB TFB TFB RAIN TFA TFA TFA TFA TFA TFA TFB TFB TFB TFB TFB TFB TFA TFA TFA TFA TFA TFA TFB TFB TFB TFB TFB TFB FA1 F81 FC1 FC2 RAIN FA1 F82 F01 FC2 RAIN TFA TFA TFA TFA TFA 8/10/90 8/10/90 8/10/90 8/10/90 8/10/90 8/10/90 8/10/90 8/10/90 8/14/90 8/14/90 8/14/90 8/14/90 8/14/90 8/14/90 8/14/90 8/14/90 8/14/90 8/14/90 8/14/90 8/14/90 8/14/90 8/18/90 8/18/90 8/18/90 8/18/90 8/18/90 8/18/90 8/18/90 8/18/90 8/18/90 8/18/90 8/18/90 8/18/90 8/20/90 8/20/90 8/20/90 8/20/90 8/20/90 8/28/90 8/28/90 8/28/90 8/28/90 8/28/90 8/28/90 8/28/90 8/28/90 8/28/90 8/28/90 10.9 10.29 42.04 39.7 34.58 42.04 39.7 34.58 1.91 8.67 9.06 8.99 8.67 9.06 8.99 43.8 51.14 39.47 43.8 51.14 39.47 8.15 8.56 7.37 8.15 8.56 7.37 50.87 48.33 44.8 50.87 48.33 44.8 3.96 1.22 .55 .42 .67 1.77 .85 9.6 17.82 .66 8.82 8.06 7.07 8.82 8.06 153 .35 .34 .36 .33 .34 .36 .33 .34 2.08 .36 .36 .36 .36 .36 .36 .34 .36 .34 .36 .35 .34 .35 .35 .34 .35 .02 .35 .35 .02 .35 .35 .35 .34 .34 .34 .31 .22 .21 .2 .2 .22 .18 .2 .21 .18 .2 6.50 10.00 4.13 5.31 5.31 4.13 5.31 5.31 8.25 11.56 31.56 27.38 11.56 31.56 27.38 5.88 7.06 7.06 5.88 7.06 7.06 27.38 29.50 30.00 27.38 29.50 30.00 5.88 7.06 4.13 5.88 7.06 4.13 5.88 2.38 4.69 4.13 1.69 4.44 3.31 5.00 3.31 .56 15.81 12.13 13.19 15.81 12.13 TFA TFB TFB TFB TFB TFB TFB TFA TFA TFA TFA TFA TFA TFB TFB TFB TFB TFB TFB FA1 F31 F82 FC2 TFA TFA TFA TFA TFA TFA TFB TFB TFB TFB TFB TF8 TFA TFA TFA TFA TFB TFB TFB TFB TFB TFB FA1 FBI FC1 8/28/90 8/28/90 8/28/90 8/28/90 8/28/90 8/28/90 8/28/90 9/ 4/90 9/ 4/90 9/ 4/90 9/ 4/90 9/ 4/90 9/ 4/90 9/ 4/90 9/ 4/90 9/ 4/90 9/ 4/90 9/ 4/90 9/ 4/90 9/10/90 9/10/90 9/10/90 9/10/90 9/10/90 9/10/90 9/10/90 9/10/90 9/10/90 9/10/90 9/10/90 9/10/90 9/10/90 9/10/90 9/10/90 9/10/90 9/12/90 9/12/90 9/12/90 9/12/90 9/12/90 9/12/90 9/12/90 9/12/90 9/12/90 9/12/90 9/17/90 9/17/90 9/17/90 7.07 .05 43.85 32.39 .05 43.85 32.39 28.77 9.36 12.79 28.77 9.36 12.79 41.3 47.6 33.35 41.3 47.6 33.35 2.91 1.45 36.96 20.64 16.4 16.58 15.25 16.4 16.58 15.25 38.48 31.4 28.15 38.48 31.4 28.15 20.87 21.67 20.87 21.67 21.36 69.12 77.54 21.36 69.12 77.54 6.28 7.54 154 .21 1.02 .2 .2 1.02 .2 .2 .2 .21 .19 .2 .21 .19 .15 .2 .15 .2 .2 .23 .23 .24 .24 .2 .23 .21 .2 .23 .21 .21 .25 .23 .21 .25 .23 .18 .23 .18 .23 .22 .22 .2 .22 .22 .2 .24 .24 .23 13.19 12.63 6.13 6.69 12.63 6.13 6.69 12.13 2.25 13.19 12.13 2.25 13.19 7.25 8.31 7.25 7.25 8.31 7.25 4.44 6.13 12.63 9.44 22.63 23.69 24.19 22.63 23.69 24.19 5.00 8.31 8.31 5.00 8.31 8.31 7.25 6.69 7.25 6.69 6.69 5.56 8.31 6.69 5.56 8.31 9.44 6.13 12.63 FC2 IRRIG. RAIN TFA TFA TFA TFA TFA TFA TFB TFB TFB TFB TFB TFB RAIN TFA TFA TFA TFA TFA TFA TFB TFB TFB TFB TFB TFB FC1 FC2 TFA TFA TFA TFA TFA TFA TFB TFB TFB TFB TFB TFB RAIN FA1 FBI F82 FC1 RAIN 9/17/90 9/17/90 9/17/90 9/17/90 9/17/90 9/17/90 9/17/90 9/17/90 9/17/90 9/17/90 9/17/90 9/17/90 9/17/90 9/17/90 9/17/90 9/19/90 9/19/90 9/19/90 9/19/90 9/19/90 9/19/90 9/19/90 9/19/90 9/19/90 9/19/90 9/19/90 9/19/90 9/19/90 9/24/90 9/24/90 9/25/90 9/25/90 9/25/90 9/25/90 9/25/90 9/25/90 9/25/90 9/25/90 9/25/90 9/25/90 9/25/90 9/25/90 10/ 2/90 10/ 4/90 10/ 4/90 10/ 4/90 10/ 4/90 10/ 4/90 30.85 3.5 .03 19.89 31.02 31.27 19.89 31.02 31.27 71.56 64.36 72.56 71.56 64.36 72.56 1.15 20.2 6.4 19.76 20.2 6.4 19.76 48.11 70.76 62.57 48.11 70.76 62.57 7.4 13.62 18.67 17.95 19.36 18.67 17.95 19.36 60.5 56.15 55.22 60.5' 56.15 55.22 1.89 1.52 1.34 1.26 3.04 .47 155 .24 .1 .22 .25 .25 .23 .25 .25 .23 .25 .25 .24 .25 .25 .24 1.92 .25 .27 .27 .25 .27 .27 .07 .23 .25 .07 .23 .25 .24 .24 .24 .24 .25 .24 .24 .25 .24 .24 .24 .24 .24 .24 .37 .25 .23 .23 .22 .23 8.88 2.8 .56 15.81 35.25 39.50 15.81 35.25 39.50 8.88 8.31 8.31 8.88 8.31 8.31 2.75 11.56 10.00 14.19 11.56 10.00 14.19 3.88 7.75 7.75 3.88 7.75 7.75 19.50 8.31 13.50 7.75 16.50 13.50 7.75 16.50 6.69 6.13 6.13 6.69 6.13 6.13 .50 12.88 8.44 5.81 29.50 2.13 TFA TFA TFA TFA F81 F82 RAIN TFA TFA TFA TFA TFA TFA TF8 TF8 TF8 TF8 TF8 TF8 F81 FC1 TFA TFA TFA TFA TFA TFA TF8 TF8 TF8 TF8 TF8 TF8 TFA TFA TFA TFA TFA TFA TF8 TF8 TF8 TF8 TF8 TF8 TFA(GRA8) TF8(GRA8) FB(GRAB) 10/ 4/90 10/ 4/90 10/ 4/90 10/ 4/90 10/11/90 10/11/90 10/11/90 10/11/90 10/11/90 10/11/90 10/11/90 10/11/90 10/11/90 10/11/90 10/11/90 10/11/90 10/11/90 10/11/90 10/11/90 10/18/90 10/18/90 10/18/90 10/18/90 10/18/90 10/18/90 10/18/90 10/18/90 10/18/90 10/18/90 10/18/90 10/18/90 10/18/90 10/18/90 10/25/90 10/25/90 10/25/90 10/25/90 10/25/90 10/25/90 10/25/90 10/25/90 10/25/90 10/25/90 10/25/90 10/25/90 5/11/91 5/11/91 5/17/91 17.94 18.42 17.94 18.42 1.3 .65 .73 38.36 35.39 37.38 38.36 35.39 37.38 81.26 78.86 58.88 81.26 78.86 58.88 .85 1.4 36.06 37.64 38.18 36.06 37.64 38.18 54.39 52.37 63.17 54.39 52.37 63.17 33.64 33.52 32.49 33.64 33.52 32.49 71.21 61.79 64.36 71.21 61.79 64.36 15.16 14.89 .99 156 .07 .16 46.37 .23 .23 .23 .23 .23 .26 .23 .16 .22 .23 .16 .22 .23 .23 .25 .24 .23 .25 .24 .21 .2 .2 .22 .21 .2 .22 .21 .21 .22 .2 .21 .22 .2 .21 .22 .22 .21 .22 .22 .23 .22 .22 .23 .22 .22 .11 .13 15.61 45.69 11.44 45.69 11.44 12.00 12.50 2.63 14.75 13.81 13.31 14.75 13.81 13.31 4.19 7.38 6.31 4.19 7.38 6.31 8.6 18.5 13.5 14.5 Ht‘h‘H .>4>O:p Ulm NQGQQO‘Q 0' 00 eraptauaw NNNNN OOOOO F01 TFA1(GRA8 TF814 TF82 TF827 TFA1 TFA2 TF81 TF85 TF87 FA1 FA2 F81 F82 F01 F02 TF812 TF82 TF823 FA1 FA2 F81 F82 FC1 F02 TFA1 TFA2 TFA3 TF814 TF82 TF827 TFA13 TFA2 TFA24 TF814 TF82 TF827 TFA1 TFA2 TFA3 TF82 TF84 TF86 TFA1 TFA2 TFA3 TF813 TF82 5/17/91 5/22/91 5/22/91 5/22/91 5/22/91 5/24/91 5/24/91 5/24/91 5/24/91 5/24/91 5/27/91 5/27/91 5/27/91 5/27/91 5/27/91 5/27/91 5/27/91 5/27/91 5/27/91 5/29/91 5/29/91 5/29/91 5/29/91 5/29/91 5/29/91 5/29/91 5/29/91 5/29/91 5/29/91 5/29/91 5/29/91 6/ 6/91 6/ 6/91 6/ 6/91 6/ 6/91 6/ 6/91 6/ 6/91 6/ 8/91 6/ 8/91 6/ 8/91 6/ 8/91 6/ 8/91 6/ 8/91 6/10/91 6/10/91 6/10/91 6/10/91 6/10/91 1.07 12.88 15.28 8.93 14.22 9.97 15.98 4.27 10.03 8.18 .55 .21 .93 .54 .73 .85 8.19 5.94 15.4 11.35 21.11 24.09 30.24 24.06 31.33 15.26 31.55 22.56 38.32 46.68 40.87 20.44 7.77 20.12 31.83 34.33 17.57 12.59 16.33 17.93 24.21 22.31 28.89 18.94 11.89 14.25 10.48 24.12 157 2.01 .05 .22 n.d. n.d. n.d. .14 .03 .05 n.d. .76 .42 .74 .47 .61 .49 .04 n.d. .15 .61 .31 .37 .23 .29 .34 .3 .3 .15 n.d. n.d. .13 .05 .18 .03 .06 .12 .07 .15 .15 n.d. .05 .05 .04 .05 n.d. n.d. .02 .03 n.d. .12 .1 n.d. .12 .12 .11 .07 .12 .11 .16 .1 .15 .12 .14 .11 .12 .1 .12 .26 .24 .19 .15 .11 .12 .08 .11 .11 .11 .1 .11 .11 .12 .12 .09 .12 .12 .12 .09 .12 .12 .11 .11 .12 .12 .12 .12 .12 1.5625 11.5625 5.25 5.25 4.75 10.5 15.25 2.125 2.125 2.125 .5 .5 2.125 1.5625 2.625 2.625 2.625 2.125 3.6875 10 16.3125 12.125 18.4375 20.5 21.5 15.8125 6.3125 4.75 3.6875 5.8125 3.1875 18.9375 1.0625 26 3.6875 4.1875 2.625 12.125 25 22 4.75 3.6875 4.1875 23.875 17.875 20.5625 2.25 5.5625 TF87 F82 FC1 FC2 TFA11 TFA2 TFA20 TF810 TF82 TF86 TFA2 TFA3 TFA4 TF814 TF82 TF827 TFA2 TFA4 TEAS TF814 TF82 TF827 TFA1 TFA2 TFA3 TF810 TF819 TF82 TFA2 TFA6 TFA9 TF814 TF82 TF827 LAEZ LAE3 LAN3 LASZ LAS3 LAW2 LAW3 LBE3 L8N3 TFA2 TFA3 TFA4 TFA1 TFA2 6/10/91 6/17/91 6/17/91 6/17/91 6/17/91 6/17/91 6/17/91 6/17/91 6/17/91 6/17/91 6/20/91 6/20/91 6/20/91 6/20/91 6/20/91 6/20/91 6/25/91 6/25/91 6/25/91 6/25/91 6/25/91 6/25/91 6/27/91 6/27/91 6/27/91 6/27/91 6/27/91 6/27/91 7/ 2/91 7/ 2/91 7/ 2/91 7/ 2/91 7/ 2/91 7/ 2/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 15.46 .25 .75 .91 22.56 21.51 21.52 22.91 17 21 22.6 22.41 22.28 24.91 20.18 27.89 22.47 19.93 23.45 27.77 16.32 22.12 20.97 22.42 22.9 28.16 33.22 23.69 23.2 25.93 23.48 29.8 25.86 22.17 22.55 27.12 27.38 2.33 1.76. 27.3 28.63 33.51 1.89 22.53 22.76 7/ 9/91n.d. 7/10/91 .32 7/10/91n.d. 158 .05 .69 .5 .27 .3 .9 .15 .08 .18 .09 .12 .06 .07 .46 n.d. .7 .11 .62 .13 .41 .09 .59 .29 .1 .09 .97 .59 .94 .22 .15 .22 .06 .04 .09 n.d. .01 .04 .54 .85 .06 .11 .03 .97 .04 .11 .09 .25 .24 .12 .13 .11 .12 .11 .1 .11 .11 .1 .11 .12 .11 .1 .11 .11 .1 .11 .11 .11 .11 .11 .11 .11 .11 .11 .1 .09 .1 .11 .11 .1 .09 .09 .1 .04 .11 .11 .1 .77 .11 .11 .11 .11 .1 .11 .11 .11 3.3125 8.875 10 10 38.625 33.625 35.4375 5.5625 4.4375 3.875 34.5625 34.5625 27325 6.6875 6.6875 4.4375 29.4375 17.375 30.9375 5.5625 4.4375 3.875 28.3125 28.875 31.375 6.125 4.4375 5 25 26.125 27.25 5.5625 5 6.125 28.875 6.125 5 2.25 1.6875 5 5 3.1875 1.5625 25.25 26.8125 12.125 3.1875 2.625 159 TF82 7/10/91 18.76 n.d. .11 4.75 TF85 7/10/91 19.25 .19 .13 5.25 TF88 7/10/91 19.88 .04 .11 5.8125 Irr. H20 7/18/91n.d. .18 .11 2.125 TFA2 7/18/91 .19 .33 .11 2.125 TFA3 7/18/91 .16 .23 .11 2.625 TFA4 7/18/91 .15 .26 .11 2.625 TF815 7/18/91 26.19 .18 .1 4.75 TF82 7/18/91 26.54 .2 .11 4.1875 TF89 7/18/91 23.74 .02 .11 3.1875 FA1 7/24/91 .9 .16 .1 1.5625 FA2 7/24/91 1 .14 .11 2.125 F81 7/24/91 .89 .2 .1 1.5625 F82 7/24/91 1.1 .13 .13 1.5625 F01 7/24/91 .64 .18 .1 1.0625 Irrig. 7/24/91 .33 .09 .12 2.125 TFA2 7/25/91n.d. .55 .13 2.625 TFA4 7/25/91n.d. .51 .11 2.625 TF812 7/25/91empty empty .1 VIAL EMPTY TF82 7/25/91 19.52 n.d. .1 4.1875 TF85 7/25/9ln.d. .43 .11 2.625 TF87 7/25/91 23.25 .32 .11 4.75 RAIN 7/29/91 1.75 1.13 .27 2.625 TFA2 7/29/91n.d. .45 .11 2.625 TFA3 7/29/91n.d. .49 .11 2.625 TFA4 7/29/91n.d. .36 .11 2.625 FA1 8/10/91 1.63 .56 .11 22.625 FA2 8/10/91 1.03 .65 .11 1.5625 F81 8/10/91 1.57 .66 .11 1.0625 F82 8/10/91 1.11 .57 .1 1.0625 F01 8/10/91 1.08 .49 .11 1.0625 F02 8/10/91 1.27 .56 .11 1.0625 TFA1 8/10/91 .1 .28 .11 2.125 TFA2 8/10/91 .06 .37 .11 2.625 TFA2 8/15/91 .52 .25 .12 4.1875 TFA3 8/15/91 .65 .2 .11 3.1875 TFA4 8/15/91 .63 .29 .11 2.625 TF813 8/15/91 15.08 .34 .11 5.8125 TF82 8/15/91 15.16 .44 .1 3.1875 TF825 8/15/91 14.38 .24 .12 5.8125 RAIN 8/16/91 FA1 8/19/91 .51 .28 .11 .5 FA2 8/19/91 .55 .27 .12 .5 F81 8/19/91 .36 .35 .1 1.0625 F82 8/19/91 .6 .41 .11 .5 F01 8/19/91n.d. .47 .12 4.1875 FC2 8/19/91n.d. .34 .13 4.75 RAIN 8/19/91 .3 .71 .13 .5 TFA2 TFAS TFA7 TF815 TF82 TF827 TFA2 TFA6 TFA9 TF82 TF85 TF88 FC1 FC2 TFA12 TFA2 TFA7 TFA14 TFA2 TFA27 LAS3 TFA15 TFA2 TFA8 TF814 TF82 TF87 TFA1 TFA2 TF81 F82 FC1 FC2 TFA1 TF82 FA1 FA2 F81 F82 FC1 FC2 8/19/91 8/19/91 8/19/91 8/19/91 8/19/91 8/19/91 8/27/91 8/27/91 8/27/91 8/28/91 8/28/91 8/28/91 9/ 4/91 9/ 4/91 ‘9/ 4/91 9/ 4/91 9/ 4/91 9/ 6/91 9/ 6/91 9/ 6/91 9/12/91 9/12/91 9/12/91 9/12/91 9/12/91 9/12/91 9/12/91 9/20/91 9/20/91 9/20/91 10/ 5/91 10/ 5/91 10/ 5/91 10/ 5/91 10/ 5/91 10/22/91 10/22/91 10/22/91 10/22/91 10/22/91 10/22/91 .72 1.29 1.38 13.92 14.81 12.93 .85 .91 1.01 5.94 5.88 5.65 n.d. .14 .4 .16 .13 .65 .49 .66 .52 .49 .86 .36 8.02 8.55 6.62 .47 .48 4.47 1.08 .95 .62 .88 .65 .96 2 1.28 1.4 1.17 1.13 160 .24 .26 .22 .25 .27 .22 .22 .22 .19 .3 .66 .22 .33 .32 .21 .21 .19 .19 .21 .24 .3 .25 .23 .2 .67 .49 .39 .21 .26 .55 .5 .45 .34 .48 .25 .71 .56 .81 .72 .54 .59 .1 .11 .11 .11 .1 .1 .14 .11 .16 .24 .72 .06 .14 .15 .15 .16 .14 .15 .15 .15 .15 .15 .15 .15 .16 .15 .12 .15 .18 .16 .16 .15 .15 .14 .07 .15 .15 .14 .15 .13 3.1875 4.75 3.6875 4.1875 5.25 4.75 3.1 4.2 4.2 4.1875 4.1875 3.1875 3.1875 3.6875 4.1875 4.1875 4.1875 4.75 4.1875 2.625 4.75 3.1875 3.6875 3.1875 6.3125 5.8125 5.8125 4.75 3.1875 5.8125 1.5625 1.0625 1.0625 1.0625 1.5625 .5 .5 .5 .5 2.125 1.0625 APPENDIX E Soil Sample Nutrient Analysis Data 162 WATER MANAGEMENT PROJECT UNIONVILLE- SOIL DATA A = SI Treatment B = DO Treatment C = ND Treatment DEPTH/ DATE N03 NH4-N P TMT REP COLLECT. in ppm ppm lb/aC A 18 9/14/89 9.6 78 A 28 9/14/89 1.67 2 A 38 9/14/89 6.61 3 A 1N 9/14/89 15.89 133 A 2N 9/14/89 3.9 46 A 3N 9/14/89 5.27 3 B 18 9/14/89 8.4 69 B 28 9/14/89 12.47 6 B 38 9/14/89 5.61 3 B 1N 9/14/89 8.41 3 B 2N 9/14/89 7.1 1 B 3N 9/14/89 3.66 3 C 1E 9/14/89 6.79 36 C 2E 9/14/89 3.25 22 C 3E 9/14/89 2.26 29 C 1w 9/14/89 3.9 69 C 2W 9/14/89 2.86 14 C 3W 9/14/89 3.84 1 A 18 4/16/90 5.87 138 A 28 4/16/90 2.03 7 A 38 4/16/90 1.75 1 A 1N 4/16/90 4.79 107 A 2N 4/16/90 1.05 2 A 3N 4/16/90 1.18 1 B 18 4/16/90 16.97 143 B 28 4/16/90 6.39 1 B 38 4/16/90 4.04 1 B 1N 4/16/90 42.37 84 B 2N 4/16/90 24.52 2 B 3N 4/16/90 13.4 1 C 1E 4/16/90 6.98 11 C 2E 4/16/90 3.62 1 C 3E 4/16/90 2.38 2 C IN 4/16/90 9.59 41 C 2W 4/16/90 1.32 1 C 3W 4/16/90 .84 1 A 18 5/14/90 32.14 169 84 67 76 118 303 93 216 93 109 101 76 93 240 135 109 101 93 109 177 107 107 168 71 71 236 80 80 219 89 89 124 107 98 219 98 107 269 nwwwwwwvn’nszvvvonnnnnwwwwmwwv>wvvnnannnwmwwwwvvvva’ 28 3S 1N 2N 3N 18 28 38 1N 2N 3N 1E ZE 3E 1W 2W 3W 18 28 3S 1N 2N 3N 18 28 38 1N 2N 3N 1E 28 3E 1W 2W 3W 18 28 3S 1N 2N 3N 18 28 3S 1N 2N 3N 18 5/14/90 5/14/90 5/14/90 5/14/90 5/14/90 5/14/90 5/14/90 5/14/90 5/14/90 5/14/90 5/14/90 5/14/90 5/14/90 5/14/90 5/14/90 5/14/90 5/14/90 5/24/90 5/24/90 5/24/90 5/24/90 5/24/90 5/24/90 5/24/90 5/24/90 5/24/90 5/24/90 5/24/90 5/24/90 5/24/90 5/24/90 5/24/90 5/24/90 5/24/90 5/24/90 6/ 7/90 6/ 7/90 6/ 7/90 6/ 7/90 6/ 7/90 6/ 7/90 6/ 7/90 6/ 7/90 6/ 7/90 6/ 7/90 6/ 7/90 6/ 7/90 6/ 7/90 163 3.62 4.39 55.04 1.85 2.22 56.44 6.96 6.19 70.83 14.71 7.82 50.57 7.58 7.29 18.81 3.21 3.31 82.93 1.34 2.32 66.02 .71 .57 62.28 1.57 1.33 73.63 18.93 11.89 70.12 14.75 6.14 31.05 3.33 6.85 10.02 .68 .94 7.46 .22 .15 11.86 .85 .57 15.28 2.68 1.42 3.8 uh U! \1 0‘ &)H\OFJP‘mtdhaxlthPJP'UFJh‘N m.» m P‘UTH m m 148 18 154 80 89 320 80 80 354 133 133 503 98 116 168 116 133 177 62 80 424 109 126 295 76 84 344 84 93 269 84 84 253 135 118 177 67 59 261 98 107 320 71 71 344 71 89 261 80 89 133 wvzuzvnwzvzvnononowmwmwwwva’wwvoonnnomwmwww>wv>wwonooo 28 3E 1W 2W 3W 18 28 3S 1N 2N 3N 18 28 3S 1N 2N 3N 18 28 3E 1W 2W 3W 18 28 38 IN 2N 3N 18 28 3S 1N 2N 3N 18 28 BE 1W 2W 3W 18 28 38 1N 2N 3N 18 6/ 7/90 6/ 7/90 6/ 7/90 6/ 7/90 6/ 7/90 6/19/90 6/19/90 6/19/90 6/19/90 6/19/90 6/19/90 6/19/90 6/19/90 6/19/90 6/19/90 6/19/90 6/19/90 6/19/90 6/19/90 6/19/90 6/19/90 6/19/90 6/19/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 7/ 3/90 8/ 8/90 8/ 8/90 8/ 8/90 8/ 8/90 8/ 8/90 8/ 8/90 8/ 8/90 164 .51 .88 8.46 1.24 .65 5.59 1.55 1.59 5.33 2.31 2.29 6.72 1.7 2.38 12.06 4.62 2.92 4.31 1.25 1.34 10.42 2.4 5.2 71.52 10.58 3.11 42.18 2.11 1.38 57.69 13.7 9.33 133.58 26.27 11.36 39.21 4.49 7.14 42.42 6.84 9.32 44.17 4.66 3.43 39.4 2.08 2.53 59.67 01 O 53 71 202 116 107 227 107 107 244 80 80 312 89 107 253 89 89 116 71 80 211 116 124 286 122 104 219 66 75 336 94 113 320 94 94 286 66 66 269 122 122 185 93 93 177 152 152 392 >>>>>>=ummuumwmzvzvzv>>>nonnanwwwmwwwasvwvwnnn0000001000502 28 38 IN 2N 3N IE 28 3E 1W 2W 3W 18 28 38 IN 2N 3N 18 28 38 IN 2N 3N 1E 28 3E 1W 2W 3W 18 28 38 IN 2N 3N 18 28 38 IN 2N 3N IE IE 1E IE IE IE IN 8/ 8/90 8/ 8/90 8/ 8/90 8/ 8/90 8/ 8/90 8/ 8/90 8/ 8/90 8/ 8/90 8/ 8/90 8/ 8/90 8/ 8/90 9/12/90 9/12/90 9/12/90 9/12/90 9/12/90 9/12/90 9/12/90 9/12/90 9/12/90 9/12/90 9/12/90 9/12/90 9/12/90 9/12/90 9/12/90 9/12/90 9/12/90 9/12/90 11/15/90 11/15/90 11/15/90 11/15/90 11/15/90 11/15/90 11/15/90 11/15/90 11/15/90 11/15/90 11/15/90 11/15/90 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 165 5.21 4.45 95.34 18.54 8.74 30.81 4.33 4.24 119.03 6.07 2.84 26.5 3.75 4.55 25.35 4.85 2.3 23.75 7.35 4.25 118.85 24.85 8.7 9.4 2.65 3.6 67.4 17.15 4.25 9.4 7.2 4.45 7.65 9.2 10 8.2 9.6 5.2 21.4 28.75 21.8 17.21 3 23.35 4 25.36 5 18.6 8. 7.15 6 .34 5 3.1 7 0‘ Ch \1 U H \O H \D 0‘ N N .p. U 0 O ‘OQQQGG \DGQQQQmeQQQQQHHNHHDHp-Jmpprpppppppupppppmpp Hoe... 0000~Jm H U (h 150 140 68 138 93 101 278 67 84 152 59 59 194 101 93 165 87 32 132 15 23 233 86 32 244 52 61 123 I70 194 I33 142 126 143 3’>‘>€V3’3’>'9€P3’>'V:>3’>'>€>3’3‘>2F3’3'?:F3’>'>€>3’>'>ivflfl>‘>:F3’D'9:>3’>'>:v3’>'> IN IN IN IN IN IS 18 IS 18 18 18 1W 1W 1W 1W 1W 1W 28 28 28 28 28 28 2N 2N 2N 2N 2N 2N 28 28 28 28 28 28 2W 2W 2W 2W 2W 2W 38 38 3E 38 3E 38 3N 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 166 6.32 10.35 24.68 26.55 7.25 8.23 12.4 22.73 20.75 14.65 15.35 12.21 14.85 34.07 17.95 8.95 4.25 4.32 13.2 4.57 5.2 2.65 4.55 4.38 5.6 4.46 8.35 O O \l N W .14-010040104041 OONO UINHQO‘UILANM 01mm 0‘ o o 0 NUIUI \DmHHhNO-‘O‘u \1 00 U! UHUU‘ULJLJHhéUNh-DO O 4.1 mwbpqpooqw UTU'I mumoo mowmmmwmw Nt‘ 0104348 mmwummmpqunmmuummmbw 2.25 15.65 4.1 3.7 5.47 8.55 6.45 6.15 4.75 68 97 198 200 37 67 87 120 41 174 74 96 101 120 55 136 60 13 12 15 15 18 26 13 14 22 44 44 37 20 28 20 20 11 35 24 30 HHNI—‘NUIU 100 103 219 232 107 105 117 177 176 176 160 112 121 168 133 176 126 82 83 84 89 71 101 61 72 84 107 116 101 71 82 118 98 80 118 81 92 84 80 109 93 82 82 84 80 71 109 80 mamwwmwwwwwwwwwmmunwwwwwwwwwmwmePP>>>>>P>>>>>>>> 3N 3N 3N 3N 3N 38 38 38 38 38 38 3W 3W 3W 3W 3W 3W IE 18 18 18 18 18 IN IN IN IN IN IN 18 IS IS IS IS 18 1W 1W 1W 1W 1W 1W 28 28 28 28 28 28 2N 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 01 am H U'IUIO‘ bU‘ImQUQO‘le-‘HUINIH 00m 010100 Mmhwumooxléwuqaaoomu 14.85 4.01 4.05 5.33 U" ubUlQuhO‘mNO‘oH O‘ HUI buwmwmuwwmum 00 Ch 10.9 2.65 5.95 3.01 3.1 5.04 6.8 4.05 14.3 4.32 2.55 3.79 7.9 2.15 8.6 3.68 01 O Hui-'HHHNNNHUNNHNHN 189 44 150 32 10 13 11 11 11 15 96 76 98 184 109 68 85 118 116 71 118 86 96 84 89 109 109 86 99 278 133 208 168 76 96 109 107 118 232 82 94 109 116 101 184 103 106 236 I33 560 118 81 91 93 107 109 109 91 n00000000mwmwmuumw0000wamwmwmwmwwwwwwwwwwwwmwwwwmwwm 2N 2N 2N 2N 2N 28 28 28 28 28 28 2W 2W 2W 2W 2W 2W 3E 38 38 3E 38 38 3N 3N 3N 3N 3N 3N 38 38 38 38 38 3S 3W 3W 3W 3W 3W 3W 18 18 IE 18 18 18 IN 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 Hmommum¢qumbphquuu~ U'IU'IO UIU'I UU‘IN mm 010‘ monummwmumbpmmwmbpmm 94 93 124 109 118 102 109 202 116 200 126 72 87 101 89 84 84 64 62 101 89 59 152 103 121 303 98 143 126 82 86 84 89 101 I32 96 92 101 98 84 143 91 102 261 124 84 84 71 000OOOOOCOOOOO‘OOOOOOOOO000000OOOOOOOOOOOOOOOOOOO IN IN IN IN IN 18 IS IS IS IS IS 1W 1W 1W 1W 1W 1W 28 28 28 28 28 2N 2N 2N 2N 2N 28 28 28 28 28 28 2W 2W 2W 2W 2W 2W 38 3E 38 3E 38 3N 3N 3N 3N 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 5/11/91 5/22/91 6/ 6/91 6/25/91 169 6.55 4.07 11.25 2.65 21.55 2.32 6.35 1.58 8.75 2.45 9.11 12.15 9.35 2.65 7.05 2.3 1.02 4.5 .74 2.45 1.15 1.5 2.57 7.15 2.36 3.15 1.15 8.76 16.8 13.65 3.8 10.55 3.4 1.65 1.85 3.51 4.4 2.8 18.9 .98 1.95 1.07 3.2 12.1 14.6 23.25 16.8 01 H 4:014 .00. O HfimOUHmUthQO-fi UIN 00 UU'IU-bO‘UI-bNmUIUt-‘CDNUUIN Mm HUI 2.35 5.12 4.55 5.3 2.02 H6 #01 0.0.0.0.... 0.0.0.0... muqmummowwmpmmpmpmwpupm UIU'li-‘UIN U'IU'IUIUIUI 01 #0110 U'lUI-hubwkbUN-bNUIUUTNbNUUI‘OobU-bbw O 108 58 86 109 62 59 67 68 82 76 98 59 91 114 93 80 101 93 81 78 84 80 76 59 61 82 59 98 84 100 109 160 98 160 84 81 90 84 98 76 67 76 89 84 107 93 101 114 126 200 0000000000000 3N 3N 38 38 38 38 38 3S 3W 3W 3W 3W 3W 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 8/15/91 5/11/91 5/22/91 6/ 6/91 6/25/91 7/ 9/91 170 2.01 1.8 5.43 9.45 4.11 2.75 .28 1.7 2.98 9.6 3.86 1.75 .14 .67 5.8 3.01 4.42 8.75 .51 6.05 4.32 3.4 5.35 4.35 .61 39 43 12 10 11 10 NUNHU 236 101 82 96 84 107 152 51 87 91 93 107 118 APPENDIX F Soil Alachlor Analysis Data Soil Sample Location SI-North, SI-North, SI-South, SI-South, DO-North, DO-North, DO-South, DO-South, ND-North, ND-North, ND-South, ND-South, I I 8888 821823 OO?O COCO ' ooc'ao oooo 0.. 4.0000800 EIBE38 ococao ococ>o ucnuou 521853 172 Date 6/7/91 6/25/91 6/7/91 6/25/91 6/7/91 6/25/91 6/7/91 6/25/91 6/7/91 6/25/91 6/7/91 6/25/91 Alachlor, ppb <0.05 <0.05 <0.05 <0.05 <0.05 <0.05 <0.05 <0.05 <0.05 <0.05 <0.05 <0.05 APPENDIX G Crop Yield, Leaf Area, Stem Volume and Plant Biomass Nutrient Analysis Data 174 5.0 0-0 Subirrigation BS Drainage Only 7'5- ace-90$ No Drainage ‘CO _ 3.5 — 3.0 '- 205 _ LEAF INDEX 2.0- 1.5- 1.0-i 054 0.0 May August 1990 1990 Leaf Index 5.0 G—O Subirrigation J BE Drainage Only 4'5 Xufi No Drainage 40- 354 3.0-l 2.5 - LEAFINDEX 2.0 ~ 0.5 -i 0.0 I June July August 1991 Leaf Index 0032 (Hmro 0343 I C2H02<~Frn I ”000 omOZuZO mmeOZ 3 u «H u u 00 O u 20 014m vrlzqmou u\ 0\oo 034” O1 Imflcmmdu u»\ a\oo Joana zonmd trad Droq {Her 434 roomdnoz £04 OOZANZA mnNm mHNm 3**u\70 {Hmro ("MFG (aura Doom uU x fiwttw 3*; *no UC\Dn 30030\Jo Uc 3m mambo NU.G uNuOON puma» pum.o pmu N.uN bkfl.u 32 NONMU NA.UN unmoow.o nuomu "$0.5 pom ”.mN bum.” um NNOOV mm.»m poo»N0.0 ommu »U&.O umm N.wN uVV.U 02 NOOOO N&.mu powpwn.o whom pwu.o n5» N.»N uuu.N O NMNOO nu.mo nA»U&m.0 nunum “NO.V uuo N.om $30.0 dedmrm ”mono nwmwom.o puma» “mm uufl .5 DCNDJOM {Hmrou paw UC\vn N.NAB¢OJ%\TO 7 1 nozm an an: . mu ucxon w. anacosuxyo Nozm an uam.ON UC\on N.NN3¢O§N\70 Nozm on »UG.O& UC\on N.OO3¢OJH\70 mzmnomo vovcr Uu¢\30 Nozm Du mmooo.oo Nozm on mmmoo.oo Nozm on ONOO0.00 0002 (HMFO 0343 I CZnOZCHFFm I 3 n mu m u 00 O u :0 034m Dr324mou 034m 01 IJDCNM4u zonm4 zoum4 F0034~oz :04 0024m24 Goon av x mm »&4&o mw.u 12 nmmw0 u0.&u am upaua pm.No wz u»OOV “3.40 om nuWAV pa.mu 02 numpa ub.mu 4043rm “3480 6 U Dcmnmom < u mrou » am Nozm 3n “04.nu Nozm a» nN&.0u Nozm on uuu.0m mzmnomo Dover v~¢\70 Nozm In omuoo.oo Nozm 0" 00400.00 Nozm 0» 00000.00 u00~ ODOt~ZO mmmmoz m\uG\0u u0\ O\0u fir04 DFO4 (”NFC 434 mHNm mHNm 3#*u\70 (nmro (HNFO {Hmro fifltfiw 3*? *»O UC\on 3¢03h\70 Uc mmmflfl mumu umm.u n0u N.0o NA0.0 m0umm.& 0500 pflm.N NO» U.ON NNU.A VNOGO.N OVVN 900.0 MNN p.05 NOA.V aflmu0.N GNON nuu.o nmm H.0u u0V.0 V0mmm.o Vhou 00.4 ppu p.40 NOV.& mmpflm.w Nmuh 0o.w paw n.00 NO0.0 mmmflfl.& mpmu u0w NAN UC\on N.»43¢03u\70 UC\on N.003¢03u\70 UC\on u.0N3¢03a\70 UC\on p.003¢03u\30 177 Unionville Plant Measurements 1990 IMTTE 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/19/90 7/19/90 7/19/90 7/19/90 7/19/90 7/19/90 7/19/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 SI D0 Leaf Leaf Area Area Index Index m‘Z/m‘z m‘Z/m‘z 2.883855 2.60015 4.39712 2.578338 4.10423 2.124808 3.78209 2.306486 3.62674 2.605071 3.34919 2.781296 3.177265 1.422302 3.3111 2.689061 6.418815 2.84354 3.288415 3.445897 3.616925 2.663192 4.43898 3.133746 3.438825 2.157726 4.06653 3.649786 2.901925 2.018408 2.75717 2.31553 3.377075 1.384796 3.655145 1.611162 3.76324 1.762782 3.18214 1.471512 3.89415 3.010588 3.18955 2.327101 2.477865 2.488962 3.170505 1.846639 2.200185 2.110245 2.604355 2.743258 2.66331 2.206071 2.67631 2.724372 3.05422 2.005906 2.87157 1.762516 2.50237 3.207162 3.37363 1.98037 3.1252 2.70123 2.78889 2.790606 3.16199 2.475396 5.01202 2.579668 3.497715 3.045900 3.7427 2.048998 2.80033 3.221792 3.5256 2.61744 ND Leaf Area Index m‘2/m*2 2.394044 3.014732 3.158112 3.091916 2.850716 2.081288 2.937012 1.6549 2.176428 2.597724 1.463548 2.401816 1.467032 2.416824 1.693224 2.149628 2.328116 2.914768 1.985076 2.15204 3.09406 1.126672 2.962472 2.715376 2.551092 1.975696 1.837408 3.223504 2.329456 2.443356 3.596761 3.218144 3.126622 3.156772 2.718056 2.52121 2.124101 2.207918 3.619943 2.441212 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 7/18/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 3.37129 3.382665 4.580485 4.357275 3.761485 3.727035 3.155529 3.367455 3.809728 3.434301 3.36284 3.507244 3.11415 3.573635 3.89168 3.014284 3.855085 3.17187 2.73403 2.86143 2.73962 2.58336 3.211 3.35673 2.56854 2.70894 2.760615 2.840435 3.430245 2.22703 2.24224 2.579005 2.42086 1.69182 1.36656 1.80804 1.81142 2.62132 2.23652 1.43858 2.29164 1.73264 1.48616 2.07532 2.10054 2.59012 1.38606 2.40448 2.808229 2.654148 2.395596 2.468148 2.857572 2.644506 2.824455 2.808229 2.539635 1.90855 1.735916 2.232006 2.385488 2.240518 2.35144 2.285472 2.104991 2.865286 2.774779 3.14944 1.628585 2.618238 2.623691 2.3807 2.637124 2.748578 2.019206 2.286669 2.600948 3.040314 1.892856 2.735544 1.893122 1.898176 2.239188 1.645742 1.621004 2.335214 2.110178 2.293984 2.00298 2.424324 2.265788 2.518089 2.413152 2.380966 1.581636 1.880886 178 2.42808 2.718056 2.714974 2.508413 2.617824 1.954524 3.076104 2.295956 2.40664 2.454076 2.871352 2.809176 2.362152 2.731188 2.345 2.273444 2.334816 2.687504 2.66794 2.37448 2.87832 2.14266 2.230028 2.459436 2.373676 1.972212 2.182324 2.962204 2.877248 3.088097 2.360544 2.3785 1.870908 1.927724 1.914324 2.500976 1.826956 2.439604 1.869836 2.991148 1.575304 2.340712 1.457652 2.150164 2.0904 2.134888 2.309892 2.319808 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 8/2/90 2.30334 2.00174 1.77346 2.18634 2.46402 2.18296 2.0046 2.30204 1.89306 2.00694 2.2373 1.75422 2.06076 2.07974 1.47602 2.32492 1.68038 1.70248 1.45366 1.46094 1.44196 2.1684 1.31768 1.00672 1.80856 1.37228 2.65382 2.01188 1.25944 1.49058 2.14344 2.06492 1.74304 1.95364 1.5405 1.41752 1.74746 1.44443 1.37852 1.20848 1.71314 2.08962 2.05244 1.73082 1.07458 1.69936 1.75162 1.6978 1.76092 1.557696 1.672076 2.25701 2.07347 2.19184 2.135448 2.240784 1.919722 2.183594 2.467682 2.095282 2.446934 2.289728 2.215514 2.96856 2.345854 2.292654 2.187052 1.935948 1.98303 1.76757 2.251956 1.870778 2.459104 1.346226 2.248232 2.435762 2.171624 1.868118 2.281216 2.043146 2.092888 2.214184 2.09076 2.582594 1.912806 1.89924 1.84072 2.230144 1.960686 2.121084 1.89126 2.12268 2.532054 2.679418 1.954302 2.463958 179 2.291668 2.203094 1.706624 1.300872 2.09308 1.69376 2.279608 2.03412 2.123096 2.597188 2.551092 1.843304 2.263528 2.451932 2.26326 2.568244 2.021792 2.514376 2.354112 2.334548 2.82472 2.473372 2.567708 2.217164 1.676072 6.543488 2.220916 1.860188 2.610052 2.338032 2.419236 1.977036 1.876 2.17482 2.585731 2.383592 2.223864 2.016432 2.007588 1.692956 2.3182 2.358668 2.276124 1.891812 1.87198 2.13328 2.263528 2.003568 8/2/90 8/2/90 8/2/90 8/2/90 1.80024 1.75604 2.04646 1.8603 180 2.37937 1.9564 1.568868 2.351164 2.51902 2.223328 2.101134 2.137568 [IF 181 Indonville Plant Measurements 1991 SI Leaf Area Index DATE m‘2/m‘2 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 1.170328 .8939892 1.222572 1.210108 1.440301 1.204008 1.170593 .9518028 .84864 1.061330 1.012799 1.026589 .8465184 1.023407 1.081751 1.210638 1.058678 .9886656 1.141686 1.267656 1.045684 1.464700 1.699455 1.641588 1.596769 1.727778 1.533386 1.712662 1.759072 1.472390 1.104823 1.497054 1.423328 5.582725 1.332015 1.183057 1.030832 1.202152 1.102702 D0 Leaf Area Index m‘2/m‘2 1.089665 1.361801 1.302411 1.156311 1.339496 1.092172 1.033797 1.019229 .9920158 .6470434 .7566982 1.000713 1.037585 .8641652 .7213738 1.070828 .8114989 .8182756 .996498 .955144 .969818 .9736599 1.092012 1.189341 1.284589 1.313777 1.075044 1.008771 1.060263 1.029901 .6589426 1.101991 1.024886 1.057008 1.026540 1.015067 .7214272 .8738234 1.078512 ND Leaf Area Index m‘2/m22 .6219416 .738276 .8301328 .977788 1.105703 1.203087 .9841048 .600096 .4121712 .8677704 .7440664 .5127136 .55272 .67116 .3482136 .2963632 .5898312 .6535256 .86198 .992264 .3990112 .7651224 .626416 .55272 .718536 .7964432 1.056748 .7324856 .7035336 .8677704 .9972648 .8232896 .6959008 .9385712 1.075172 .4061176 .6164144 .7043232 .4537568 In‘ 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 6/19/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 1.246970 .975936 .9780576 .6123468 .9748752 .7635108 .8259654 .9157356 .6584916 .937482 .1819272 1.037728 1.056689 .6608784 1.471064 1.370288 1.225224 1.353316 1.003252 .8687952 1.393891 1.154681 .9512724 1.032689 .8733036 .9022104 .3338868 .9555156 .9655932 .851292 .7746492 3.641196 3.797664 4.844408 4.685819 4.727720 4.718704 4.989473 3.961292 4.434409 4.365192 4.365457 4.433083 3.109735 3.930264 2.17464 3.864494 4.109274 1.116398 1.185552 .9613871 .9082939 1.075151 1.278132 .4997698 1.171519 .8518390 .9841185 1.181390 .8799064 1.056795 1.397072 1.345899 1.359506 1.087850 1.210365 1.506780 1.189501 .8681672 1.340563 1.084435 .9793694 1.244195 1.222958 .9662962 1.408117 1.168317 .8997563 1.439279 3.441453 3.568984 3.486809 3.8686 3.136501 3.034316 2.890511 3.075670 2.916924 3.310721 3.491878 3.322194 3.241086 3.175720 3.237084 3.495347 3.004435 182 .9512048 .5063968 .7485408 .806708 .6822144 .8564528 1.107546 1.133602 1.132550 1.029902 .7085344 .7311696 .6624744 .5379808 .6674752 .7530152 .8375024 .3483189 .2942050 .1108598 .3516352 .143444 .2376696 .6322064 .380324 .4021696 .318472 .2021376 .4176984 .4376490 .6569998 3.426338 3.505561 3.572150 3.434497 4.065124 4.774448 3.523458 2.708854 3.234202 3.527406 3.248151 2.371695 3.259206 2.669374 2.680692 1.404962 2.986794 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 2.890150 4.577882 4.377656 4.347954 4.193077 4.047217 4.410011 4.499383 3.986486 3.808802 4.054643 3.654986 2.739516 2.715648 3.841952 4.075594 4.000542 3.500110 3.528751 2.966792 3.287419 3.474650 4.012476 3.059612 3.545989 2.963080 2.651204 3.501170 3.094884 3.211837 2.767892 3.356106 3.144211 2.735273 3.556067 3.531668 3.382626 3.194599 2.878746 3.259573 3.473590 2.932847 3.389256 3.887036 3.12273 3.481015 3.779896 3.972166 2.887843 2.656528 2.934266 3.201333 2.891578 2.937735 3.330998 3.042320 3.265899 2.967616 2.719226 3.082874 2.757378 2.761113 2.684008 2.981223 3.551642 3.135700 3.225879 3.007903 3.484408 3.169851 2.805669 2.809404 2.654126 3.227746 2.785659 2.584758 3.319792 2.644788 3.178122 3.140236 3.337935 3.279506 2.973219 3.145305 3.693579 3.091945 3.085595 3.113823 3.095947 3.212539 3.398765 3.315524 3.284575 2.984958 2.758712 2.762180 183 3.722964 3.229464 3.259995 2.332794 2.220355 2.487766 2.308264 2.077701 2.657267 2.859142 3.151030 3.515299 3.470029 4.192250 2.760178 2.728594 3.233938 3.703224 3.346904 2.615682 2.662479 1.656054 3.349852 2.044538 2.293525 2.896779 3.221831 3.463975 3.400018 3.682168 3.961950 3.699013 4.438342 3.334744 3.225779 3.735071 4.141715 4.0138 3.869303 2.010848 1.739489 1.635525 2.364062 1.082805 1.549458 3.169981 1.581306 2.016112 ‘\ 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/ 9/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 3.349476 3.584974 3.543337 4.456156 3.505944 2.713739 2.416715 3.259944 2.809953 .5306652 2.614554 2.693636 3.516393 3.373185 3.688720 3.011452 3.347301 2.921390 2.851696 2.499669 2.871373 2.596308 2.411411 2.339435 2.456813 2.228051 2.846657 3.096953 3.577124 4.259483 2.741585 3.209610 2.628662 3.395674 2.367122 3.489183 2.996548 3.520795 3.348468 2.929187 2.893014 3.172535 2.889248 2.609409 2.465458 3.263551 2.941386 2.410403 3.165048 3.012972 2.518592 3.443588 2.173033 2.076238 2.148754 1.653093 2.046783 2.107560 2.171912 2.614160 2.355204 2.976528 2.212359 2.071649 2.266199 2.851772 2.365502 2.798839 2.613039 2.256861 1.884195 2.311342 2.311022 1.641994 1.900416 1.785746 2.161454 2.068821 2.174633 1.948014 2.411765 2.174367 2.189094 2.296134 2.695907 2.569337 2.075651 2.383271 1.900256 2.355097 1.635110 1.685642 1.618942 2.001960 2.299603 184 2.035326 1.643158 2.100336 2.0069 3.232359 3.131448 3.574203 2.883567 2.632421 2.289524 2.609207 2.253413 2.885883 3.539145 2.670532 2.679113 1.950207 2.513823 2.596994 3.106708 2.026587 2.416387 3.356748 2.123340 2.753809 2.714171 2.459393 2.616366 2.666532 2.176769 2.738649 2.320634 2.688641 3.031748 3.400018 3.469344 2.838033 2.743492 2.246149 2.890094 3.979426 3.053436 2.924310 2.544091 3.070965 2.733964 2.537669 2.289314 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 7/24/91 3.183249 2.749541 2.796375 3.109894 3.182877 2.604794 3.182294 2.798762 2.980689 2.417192 2.756277 3.065500 2.933589 2.655129 3.420868 2.929505 3.245942 2.516271 3.035850 2.831965 2.939212 2.745403 2.810218 2.835731 3.402092 2.505397 3.491676 1.555657 2.438232 1.851966 2.028534 1.829181 1.466173 2.307073 2.468380 1.678385 1.039026 1.302358 1.570758 1.847216 1.617608 2.188934 1.751062 1.818402 1.527003 1.777635 .9116022 1.830622 2.084615 1.663605 1.558165 1.625506 1.547814 185 2.790394 3.063964 2.372327 2.746439 2.360799 2.914993 3.492453 2.858089 2.730805 3.766181 3.730807 3.405282 2.881882 2.453603 2.613365 2.678481 2.769338 1.354322 2.493662 2.858510 2.461288 2.533984 2.783024 2.448234 2.384697 2.569253 2.628736 186 Unionville Kernel Biomass A = SI 8 = D0 C = ND PLANT BIOMASS ID DATE (G) Kg/ha AN 8/8/90 145 9425 AS 8/8/90 143.5 9327.5 8N 8/8/90 121.7 8093.05 8S 8/8/90 128.2 8525.3 C8 8/8/90 130.9 8770.3 0W 8/8/90 128.9 8636.3 AN1 9/4/91 155.1 10283.13 AN2 9/4/91 189.9 12590.37 AN3 9/4/91 135.4 8977.02 AN4 9/4/91 162.9 10800.27 AN5 9/4/91 175.9 11662.17 AN6 9/4/91 147.1 9752.73 AN7 9/4/91 155.5 10309.65 AN8 9/4/91 151.8 10064.34 AN9 9/4/91 151.3 10031.19 ANIO 9/4/91 135.8 9003.54 A81 9/4/91 157.5 10442.25 A82 9/4/91 156.7 10389.21 A83 9/4/91 168.6 11178.18 AS4 9/4/91 176.6 11708.58 ASS 9/4/91 149.6 9918.48 AS6 9/4/91 163.1 10813.53 A87 9/4/91 102 6762.6 ASB 9/4/91 268.7 17814.81 AS9 9/4/91 321.8 21335.34 A810 9/4/91 181.9 12059.97 BN1 9/4/91 35.9 2394.53 BN2 9/4/91 134.6 8977.82 BN3 9/4/91 75.8 5055.86 8N4 9/4/91 126 8404.2 8N5 9/4/91 109 7270.3 8N6 9/4/91 111.9 7463.73 BN7 9/4/91 102.5 6836.75 BN8 9/4/91 128 8537.6 BN9 9/4/91 106.2 7083.54 BNIO 9/4/91 141.8 9458.06 881 9/4/91 127.3 8490.91 882 9/4/91 125.3 8357.51 2883 9/4/91 108.4 7230.28 BS4, 9/4/91 126 8404.2 835 9/4/91 108 7203.6 886 9/4/91 126.4 8430.88 887 888 889 8810 CNI CN2 CN3 CN4 CN5 CN6 CN7 CN8 CN9 CNIO C81 C82 C83 C84 C85 CS6 CS7 CS8 CS9 C810 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 98.1 147.3 109.5 119.3 177 113.9 42.8 116.5 151.7 61.5 136 118.7 127.3 93.1 97.4 137.6 146.3 2.9 71.5 147.3 155.3 97.2 130 187 6543.27 9824.91 7303.65 7957.31 11646.6 7494.62 2816.24 7665.7 9981.86 4046.7 8948.8 7810.46 8376.34 6125.98 6408.92 9054.08 9626.54 190.82 4704.7 9692.34 10218.74 0 6395.76 8554 188 Unionville Watertable Management Project 1990 Biomass 7/18/90 g/m‘2 REP SI DO ND 1 500.91 460.4960 437.574 2 593.6163 402.5316 579.0948 3 584.4025 288.5488 533.719 4 782.6688 306.3378 511.676 5 898.6938 471.4311 421.3935 6 688.37 486.1574 353.2713 7 556.6475 151.7936 532.5465 8 531.7363 421.1497 286.087 9 697.925 370.6809 290.1908 10 727.8413 714.8814 466.4175 11 625.6938 508.4844 176.5755 12 619.8925 420.0192 424.3248 13 810.8788 234.4556 117.4815 14 532.76 536.3932 503.9375 15 525.3663 313.4269 220.5443 16 256.2338 369.1233 317.979 17 734.6663 190.3017 511.5588 18 653.5625 191.8959 551.7755 19 866.8438 275.5650 268.9685 20 480.5488 155.3484 432.0633 21 740.695 692.1433 450.4715 22 512.74 422.0038 110.5638 23 315.0425 369.7171 630.333 24 586.6775 230.6621 486.9363 25 345.3 421.1497 519.18 26 327.1 357.8502 341.1945 27 461.4388 234.4556 314.9305 28 562.2213 346.8786 554.0033 29 486.35 342.3748 274.831 30 506.4838 230.6889 222.8893 31 346.665 616.0491 647.3343 32 746.155 542.8976 476.8528 33 669.0325 469.9255 427.9595 34 489.7625 332.2190 395.4813 35 532.76 386.2614 411.5445 36 662.5783 480.9644 346.9398 37 674.6508 335.4956 258.2988 38 761.6609 224.1248 227.3448 39 390.7123 531.122 339.6703 40 608.2520 387.0498 203.8948 41 640.3888 511.3383 263.8095 42 695.3491 443.2589 415.4138 43 646.8626 428.8284 320.793 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 8/ 2/90 w "0 \qumthNI-‘M 656.0510 438.0983 734.5312 677.6511 404.9123 575.4901 471.7754 630.0129 630.0129 572.0947 707.1739 890.6346 625.6554 512.7836 660.5112 562.2568 579.2226 373.7912 316.4758 499.2958 675.8206 663.2793 544.3847 517.6099 523.2086 518.4962 313.1609 SI 1134.839 1536.149 1276.003 1484.165 1817.68 1398.17 952.3838 1456.41 1454.704 1248.134 1112.999 1328.214 1187.278 1258.599 1078.533 791.0863 1284.306 578.9521 615.0284 313.5008 438.1384 555.0953 301.2814 428.712 245.6541 404.8551 466.883 419.9839 569.9913 437.091 288.8293 428.3629 303.027 601.9944 174.3163 307.3329 396.3598 331.1898 420.333 528.6781 325.2546 648.0789 597.3394 334.1505 g/m“2 DO 996.622 911.7846 810.8875 805.6506 1020.595 1117.652 442.5606 875.9411 917.8361 1270.569 925.2841 980.6786 639.6999 1352.264 1014.195 1095.657 598.5031 189 252.788 345.7673 257.8298 440.388 390.5568 332.6353 292.653 522.1113 341.0773 308.8335 332.6353 258.2988 395.4813 310.475 384.9288 354.092 268.9685 333.6905 309.1853 352.216 396.771 343.774 227.462 290.1908 418.6968 501.827 310.5804 ND 1157.372 1406.059 1354 1237.454 1213.066 943.2733 1133.687 890.5108 849.9423 1034.025 411.31 1246.951 376.2523 1368.305 697.7518 893.2075 1329.378 1*. 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 1422.058 1565.269 1302.393 1304.554 1308.649 844.0938 1398.739 745.3588 911.775 1159.864 1258.599 1142.688 1274.865 920.7613 1405.678 1284.079 1274.41 1148.261 1398.136 1265.262 1233.909 902.5352 1503.547 1137.085 1079.080 1515.307 1398.136 1181.732 1246.950 1053.372 1131.504 1290.345 1198.475 1315.427 1320.530 1129.520 1310.820 1399.002 1004.725 1226.379 1164.990 1098.258 1145.599 906.1717 819.7353 1092.438 1404.645 1385.117 706.6155 861.5106 530.4238 1444.549 910.6209 949.4901 577.4393 972.7651 842.076 684.737 992.898 950.8866 521.2301 1283.952 1005.816 1413.71 1289.072 1175.258 1159.547 892.35 648.5444 1168.857 962.175 1026.298 980.0968 1061.908 1089.257 1228.325 897.936 891.5354 1085.533 844.2871 1115.325 729.425 1175.258 1271.849 1145.000 1334.226 1109.389 723.7226 1100.196 992.0834 1303.619 741.4116 801.4611 965.7826 1083.671 1064.701 190 1135.681 814.5328 1188.560 1170.387 293.0048 1205.679 984.6625 1081.159 902.0013 746.0588 1379.561 1008.816 705.4903 1362.911 1251.524 907.8638 1066.620 809.3738 38.455 875.8545 651.6725 1166.048 519.7663 905.5188 1203.686 777.599 717.9188 975.048 740.6653 1203.686 1093.705 1146.585 768.688 1140.136 1210.603 871.1645 1063.924 794.6003 910.4433 846.073 928.7343 732.106 761.7703 1085.615 621.7738 826.7268 1221.977 833.0583 66 67 68 69 70 1103.600 1233.909 1027.683 1270.175 1016.967 1518.680 1124.635 1373.793 1412.779 1494.940 191 578.0395 719.5603 1007.761 1477.113 1140.136 192 Unionville Watertable Management Project 1991 Biomass 6/19/91 g/m*2 REP SI DO ND 1 328.0275 336.2624 306.4617 2 312.6173 345.0667 304.8982 3 335.7026 345.7261 306.5094 4 328.7285 332.2364 313.6545 5 316.0008 328.0560 321.1686 6 326.6985 325.7496 332.6569 7 338.8155 333.2684 333.0526 8 316.3456 328.0808 306.9809 9 317.4132 330.8356 299.7492 10 310.6447 312.5616 323.2567 11 321.0082 317.2938 317.5452 12 331.9656 328.6367 303.6490 13 316.3118 334.3538 306.2028 14 324.5017 331.0358 308.2710 15 326.5736 315.5676 296.1711 16 341.0974 313.6704 296.5068 17 324.4762 304.7430 305.7643 18 320.9801 310.9862 312.0665 19 341.5597 332.1417 320.1922 20 349.7977 309.0005 324.9405 21 331.3719 324.0049 300.9950 22 342.9078 322.8066 308.7969 23 356.8512 341.1396 299.7133 24 325.3811 338.2297 300.1644 25 338.9617 342.2803 302.2048 26 346.8411 348.9336 306.7388 27 348.5874 333.8869 313.6867 28 345.4890 330.5704 303.7563 29 347.7509 331.2365 300.7163 30 342.7702 329.4470 305.8276 31 311.9956 315.4241 318.1388 32 339.2679 336.8276 303.4402 33 340.4076 324.3234 304.1655 34 323.5303 331.9433 312.3544 35 343.1933 326.9772 315.8244 36 323.9623 332.6540 301.0035 37 337.2476 310.4066 301.3508 38 335.8955 330.7615 310.3932 39 325.7461 350.1462 298.7242 40 341.5742 330.9530 326.0157 41 326.9611 352.3338 307.7757 42 320.7690 325.3861 315.6303 43 306.6558 325.3905 312.9661 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 7/9/91 REP 311.9270 308.3988 320.4525 316.9387 309.7188 322.1928 291.4183 324.8532 325.7755 308.1828 345.9879 342.7829 343.5146 335.8955 330.3746 312.7128 352.3657 343.5566 327.1556 330.9409 307.8183 323.5753 294.8984 336.1898 331.0718 318.5182 313.1609 SI 568.9917 582.6899 621.2778 711.3573 664.0842 683.2503 680.2920 624.1615 775.4303 659.6105 639.6031 771.3927 547.7144 677.7019 420.7320 581.1642 337.3506 338.2297 308.3051 344.8032 318.5624 345.3020 349.9470 312.0748 331.5477 352.5167 353.8620 351.4804 334.9028 353.0368 373.7327 346.9315 321.0441 346.2120 348.4299 316.4345 329.2504 343.5319 324.4860 346.4059 353.1340 304.8529 334.1505 /m“2 DO 715.1677 677.0910 591.9774 638.6841 722.7375 746.5099 661.8506 661.9240 560.7161 581.2883 650.1549 668.4419 633.0492 687.3575 846.4959 739.1651 193 311.6120 311.8642 336.8704 339.7418 340.2142 331.5349 312.7893 315.0197 304.8803 303.2413 305.3614 323.9964 323.8633 296.2292 293.4330 289.6522 294.4037 288.4775 290.4305 303.9688 295.5870 295.7534 294.9679 291.6822 295.0040 295.6198 310.5804 ND 494.1415 565.3579 577.9654 551.4712 705.5641 768.4560 637.6532 462.6640 533.1175 573.2526 497.2174 467.9671 573.6259 509.3151 449.8491 353.2522 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 578.3310 433.3979 720.5361 687.5568 763.7526 666.9554 643.1164 620.1401 873.3785 643.8717 656.7373 694.0031 594.0418 533.8855 476.8726 644.1477 627.8236 625.7585 603.3269 628.2362 512.2037 596.9153 626.8072 672.9183 619.0530 517.5124 605.2422 577.3229 666.8062 618.3980 569.6614 543.1992 576.7607 746.4972 644.8360 801.1048 660.0661 665.5271 698.5653 616.1010 609.3040 678.0328 566.4065 660.5618 630.8924 556.7921 639.4871 752.6418 795.8632 728.2852 663.4253 669.4269 710.4882 810.4627 767.3217 882.3212 679.6201 757.7403 712.4510 693.3036 632.8927 644.3029 700.1334 529.4182 574.0175 620.2971 596.4209 592.2789 687.7123 676.4755 754.8452 739.2178 700.9710 554.2646 642.6209 702.1034 471.1855 646.7836 508.3929 774.8627 626.2142 648.2447 658.1383 650.9988 664.5083 778.8796 639.1000 512.3738 621.5961 525.0951 787.8454 667.8104 609.6147 528.3251 610.8402 628.9380 194 513.5182 590.1543 564.9700 561.7459 513.0862 436.8992 423.6176 373.3997 416.4338 443.9178 506.4020 485.8481 567.5703 498.2551 536.7247 487.4018 463.9184 562.1208 566.7666 499.0812 504.8178 438.3354 361.1035 469.6904 413.7602 457.9894 415.2078 513.3328 520.5930 554.0365 541.1568 578.9405 536.1465 546.3165 471.8854 451.1171 440.7456 497.2358 529.9821 525.2354 363.7744 388.7200 364.1188 400.4681 318.1269 388.4151 442.9212 333.7061 65 66 67 68 69 70 7/24/91 REP NIH 773.3109 579.6983 684.8846 817.9071 686.2783 768.3441 SI 931.8723 1022.142 1124.296 1225.342 1286.642 1046.208 1286.930 991.0234 1130.619 1098.322 1001.073 972.5914 734.8732 1055.737 562.1573 874.0404 901.2404 700.7714 1297.179 1450.969 1137.874 1077.011 1035.777 1093.991 1417.196 1019.132 1047.869 1181.617 943.1548 748.0487 628.4068 1095.181 1070.232 977.1468 935.0379 1033.675 841.1904 921.2084 612.5160 651.3688 690.3797 439.8241 634.4026 722.4121 g/m‘2 D0 1360.599 1250.658 999.5136 783.3664 1051.141 1180.478 1290.197 1204.243 917.8541 1020.917 1216.779 1170.880 1333.358 1162.984 1209.678 1261.721 1149.914 1149.904 1096.745 1115.518 1369.145 1292.285 1070.766 1384.140 1106.664 1239.488 1164.334 960.2816 996.0387 1092.206 1127.985 927.4779 975.7307 1247.860 994.9117 945.8489 1178.811 1246.057 195 388.5757 370.8063 336.9631 372.4790 373.7957 477.3663 ND 640.5552 594.5721 757.5153 852.1733 798.5191 1100.313 860.4043 593.4777 612.0859 695.2386 616.3618 538.8648 605.1646 587.1281 741.4709 433.1910 660.6954 726.3277 723.5766 676.0892 571.5645 558.0603 564.0717 487.8386 510.4626 612.5814 609.7941 569.5685 822.9998 728.6803 791.5902 608.5561 611.3785 943.1129 783.1773 721.6030 584.0854 581.9241 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 978.2900 1140.622 956.2350 926.2351 937.2970 772.5707 1074.805 981.9798 966.1588 827.9240 867.9006 905.2575 898.8331 1262.406 1121.405 947.1100 1109.921 882.6343 836.4219 1109.029 796.9225 948.9908 898.9085 871.8028 1030.537 1247.526 1107.201 856.8759 1057.283 1173.904 1168.431 1268.379 1191.103 1193.927 1201.128 909.7533 1245.621 1140.580 741.3610 1123.695 843.2762 1233.236 1016.018 1063.689 1001.201 1189.230 1156.712 1376.967 1245.065 776.5914 987.3966 1008.995 1106.887 1215.323 987.7504 977.5465 869.6836 890.6707 931.8097 1156.469 1100.380 609.0925 1045.000 1229.527 196 424.1287 692.3776 543.0318 581.0646 582.4017 637.9169 680.0975 736.6343 751.0615 714.7080 843.6119 761.2475 742.6868 699.5316 662.1231 758.5745 764.7254 771.5429 478.6477 471.1298 528.5958 586.4576 339.5009 509.3520 620.3113 454.3770 509.6126 535.6799 450.4035 499.8998 487.0204 644.1118 197 Unionville Plant Nutrient Content A = SI 8 = DO C = ND PLANT % ID DATE N P K A 7/25/90 .93 .1 1.27 8 7/25/90 1.19 .11 1.33 0 7/25/90 .54 .06 1.14 A 8/8/90 1.02 .14 1.74 8 8/8/90 1.24 .1 1.28 0 8/8/90 .95 .08 1.27 ANI 7/11/91 1 .14 1.1 ANI 7/25/91 1.3 .19 1.25 ANI 9/ 4/91 1.4 .18 1.5 ANII 7/11/91 1.2 .18 1.16 ANII 7/25/91 1.2 .15 1.16 ANII 9/ 4/91 .9 .14 1.25 ASI 7/11/91 1.1 .13 1.15 ASI 7/25/91 .8 .08 1.33 ASI 9/ 4/91 .7 .09 .9 ASII 7/11/91 1.1 .14 1.03 ASII 7/25/91 .9 .09 1.01 ASII 9/ 4/91 .9 .1 1.17 8NI 7/11/91 1.5 .2 1.91 8NI 7/25/91 1.1 .21 1.67 8NI 9/ 4/91 1.1 .17 1.49 8NII 7/11/91 1.4 .23 1.46 8NII 7/25/91 1.5 .23 1.95 8NII 9/ 4/91 1.7 .22 1.87 381 7/11/91 1.3 .19 2.22 BSI 7/25/91 1.4 .23 1.51 BSI 9/ 4/91 1.1 .21 1.86 8SII 7/11/91 1.8 .32 2.01 8811 7/25/91 .9 .18 1.83 BSII 9/ 4/91 1.5 .26 1.79 CNI 7/11/91 1.8 .31 3.46 CNI 7/25/91 1.4 .24 3.13 CNI 9/ 4/91 2.3 .28 2.71 CNII 7/11/91 2.7 .38 2.51 CNII 7/25/91 2.1 .28 3.24 CNII 9/ 4/91 1.8 .28 3.18 CSI 7/11/91 2.1 .3 2.63 CSI 7/25/91 1.9 .28 2.98 CSI 9/ 4/91 2.4 .31 4.73 CSII 7/11/91 2 .24 1.86 CSII 7/25/91 .9 .33 3 CSII 9/ 4/91 1.5 .27 3.44 Unionville Kernel Nutrient Content 8/8/90 8/8/90 8/8/90 8/8/90 8/8/90 8/8/90 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 9/4/91 0 0.... 0.)th0145be01014 HHHHHHHHHHHH 198 .31 .34 .42 APPENDIX H Soil Nutrient, Crop Yield, Leaf Index and Plant Biomass Statistical Analysis 200 —1.41076 + 10509.01 .880 .175367 It X 1400- 1200- 1000“ Biomass, q/m’ 800 -‘ 600 — 400 - 200 - O 1990 i | l I I I l l I 3500 4000 4500 5000 5500 6000 8500 7000 7500 Slolk Volume. cm -- J/m' V l l 20 00 2500 3000 8000 1990 Stem Volume vs. Biomass onnn “W Y 88 R2 = 287.239 22606.94 .625 + .728575E—01 at X 1500- = 1600— 14004 1200— 1000— Biomass. g/m’ BOO -— 600 -‘ 400 - 200 - n v 0 1991 0.0 I 2000.0 4060.0 I 6000.0 8000.0 I ‘I .OE-o-04 I 1.2E+04 1.4-E +04 Skalk Volumc. cm—tJ/m' 1991 Stem Volume vs. Biomass 201 Unionville Soil Nitrate-N Student t-Test Year 1990 1991 t t Depth A to B A to C 0.0-0.3m 2.132 .021 0.3-0.6m 2.717 2.335 0.6-0.9m 1.568 2.611 0.0-0.3m .073 1.57 0.3-0.6m 5.004 .708 0.6-0.9m 3.007 .538 Soil Ammonia—N Student t-Test Year 1991 Soil Orthophosphate-P Student t-Test Year 1990 1991 t t Depth A to B A to C 0.0-0.3m 2.916 2.429 0.3-0.6m 1.382 1.614 0.6-0.9m .107 1.937 t t Depth A to B A to C 0.0-0.3m 4.281 14.675* 0.3-0.6m 2.113 .791 0.6-0.9m 1.053 .59 0.0-0.3m 4.471 4.667 0.3-0.6m 1.455 .577 0.6-0.9m 2.114 1.342 Soil Potassium Student t-Test Year 1990 1991 t t Depth A to B A to C 0.0-0.3m 2 2.512* 0.3-0.6m .107 .053 0.6-0.9m .462 .213 0.0-0.3m .572 3.881* 0.3-0.6m 4.744 .132 0.6-0.9m 1.375 2.867 t B to C .61 .403 1.158 .765 1.283 3.452 t B to C .528 1.208 3.721 t B to C 15.324* 1.244 .327 1.372 1.138 .872 t B to C 5.463* .338 1.154 2.467* 4.296 .588 202 UNIONVILLE WATERTABLE MANAGEMENT PROJECT STATISTICAL COMPARISON OF YIELD: 2-SAMPL8 t-TEST ABOUT u ALPHA=0.05 t(1,0.025)= 12.71 1990 SI DO AVE AVE YIELD YIELD A to B REP mtons/ha mtons/ha DIFF NORTH 2.52 2.12 .4 SOUTH 2.32 2.32 0 SUM 4.84 4.44 .4 MEAN 2.42 2.22 .2 STD .2 n 1 t 1 1991 SI DO ND AVE AVE AVE YIELD YIELD YIELD SI/DO SI/ND DO/ND REP mtons/ha mtons/ha mtons/ha DIFF DIFF DIFF NORTH 3.02 1.91 1.66 1.11 1.36 .25 SOUTH 2.9 1.84 1.7 1.06 1.2 .14 SUM 5.92 3.75 3.36 2.17 2.56 .39 MEAN 2.96 1.875 1.68 1.085 1.28 .195 STD .025 .08 .055 n 1 1 1 t 43.4 16 3.545455 203 LEAF INDEX ANOVA 7/18/90 Source d.f. 88 MS F Total 209 98.41615 Block 69 22.36283 .324099 1.086159 Treatment 2 34.87551 17.43776 58.4395 Error 138 41.17781 .2983899 FPRLSD Significance Test t(0.05)= 1.96 FPLSD= .1809731 MEAN LEAF INDEX DIFFERENCE COMPARISON IN MEAN A to 8 .8892999* A to C .8373225* B to C .0519774 LEAF INDEX ANOVA 7/10/91 Source d.f. 88 MS F Total 209 97.94504 Block 69 26.0521 .3775666 1.027117 Treatment 2 21.16435 10.58218 28.78732 Error 138 50.72859 .3675985 FPRLSD Significance Test t(0.05)= 1.96 FPLSD= .2008671 MEAN LEAF INDEX DIFFERENCE COMPARISON IN MEAN A to 8 .5727133* A to C .7419019* B to C .1691886 F(0.05) 1.31 3.00** F(0.05) 1.31 3.00** 204 Unionville Watertable Management Project ANOVA - RANDOMIZED BLOCK DESIGN Biomass r= 70 t= 3 BIOMASS ANOVA 7/18/90 Source d.f. Total 209 Block 69 Treatment 2 Error 138 88 MS F 5342029 1167149 16915.21 .9915966 1820798 910399.1 53.36905 2354081 17058.56 FPLSD Significance Test t(0.05)= 1.96 FPLSD= 43.27063 MEAN BIOMASS INDEX COMPARISON A to B A to C B to C BIOMASS ANOVA 8/ 2/90 Source d.f. Total 209 Block 69 Treatment 2 Error 138 ABSOLUTE DIFFERENCE IN MEAN 179.7948* 211.4395* 31.64475 88 MS F 15099709 4172293 60468.02 1.01536 2709062 1354531 22.74485 8218354 59553.29 FPLSD Significance Test t(0.05)= 1.96 FPLSD= 80.84905 MEAN BIOMASS INDEX COMPARISON A to B A to C B to C ABSOLUTE DIFFERENCE IN MEAN 213.9255* 261.0025* 47.077 F(0.05) 1.31 3.00** F(0.05) 1.31 3.00** 205 BIOMASS ANOVA 6/19/91 Source d.f. 88 MS F Total 209 60091.62 Block 69 10295.47 149.2097 .7521629 Treatment 2 22420.52 11210.26 56.51071 Error 138 27375.63 198.3741 FPLSD Significance Test t(0.05)= 1.96 FPLSD= 4.666213 MEAN ABSOLUTE BIOMASS INDEX DIFFERENCE COMPARISON IN MEAN A to B 4.401294 A to C 19.38433* B to C 23.78562* BIOMASS ANOVA 7/9/91 Source d.f. SS MS F Total 209 2840511 Block 69 399493.9 5789.767 .7216696 Treatment 2 1333879 666939.5 83.13115 Error 138 1107138 8022.739 FPLSD Significance Test t(0.05)= 1.96 FPLSD= 29.6745 MEAN ABSOLUTE BIOMASS INDEX DIFFERENCE COMPARISON IN MEAN A to B 20.66543 A to C 157.7828* 8 to C 178.4482* BIOMASS ANOVA 7/24/91 Source d.f. 88 MS F Total 209 13304311 F(0.05) 1.31 3.00** F(0.05) 1.31 3.00** F(0.05) Block 69 Treatment 2 Error 138 206 1461199 21176.79 .8185922 8273084 4136542 159.8987 3570028 25869.77 FPLSD Significance Test t(0.05)= 1.96 FPLSD= 53.28664 MEAN BIOMASS INDEX COMPARISON A to B A to C B to C ABSOLUTE DIFFERENCE IN MEAN 88.35127* 369.8605* 458.2118* 1.31 3.00** REFERENCES Alvino, A., G. Zerbi. 1986. Water table level effect on the yield of irrigated and unirrigated grain maize. Transactions of the ASAE, 29(4):1086-1089. ASAE, St. Joseph, MI. Baker, J.L., K.L. Campbell, H.P. Johnson, J.J. Hanway. 1975. Nitrate, Phosphorus, and sulfate in subsurface drainage water. 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