THE VERTICAL AND HORIZONTAL REDTBTRTBUTTON 0F NITROGEN, CHLORIDE, AND PHOSPHORUS ~ Bv PREczPTTATTON AND SURFACE RUNOFF ON TWO SMALL WATERSHEDS ' Thesis for the Degree. of- M. S. MICHIGAN STATE UNIVERSITY ROBERT KINGSLEY HUBBARD ' 1975 ‘ WWII”?lllllllfllllllllllillHillllIHIIIIIIUHIIIHIM 3 1293 104199305 ABSTRACT THE VERTICAL AND HORIZONTAL REDISTRIBUTION OF NITROGEN, CHLORIDE, AND PHOSPHORUS BY PRECIPITATION AND SURFACE RUNOFF ON TWO SMALL WATERSHEDS BY Robert Kingsley Hubbard Causes of runoff over a one and one half year period were determined and changes in sediment and nutrient con- tents of surface runoff were related to time of year and field operations. Leaching of nutrients was traced during the summer and downlepe movement of nutrients was related to surface runoff. Comparisons of phosphorus status were made between a watershed profile and a nearby virgin pro- file. The magnitude of runoff during the summer months increased with rainfall intensity, duration of rainfall after the start of runoff, and compactness of the soil sur- face. During the winter months runoff depended on the amount of rain and accumulated snow on the watersheds and the rise in temperature above 32 F. Analyses showed that sediment content of runoff samples during the summer was related to field Operations. Highest sediment concentrations were found in the first Robert Kingsley Hubbard runoffs after plowing and planting. Winter runoff sedi- ment concentrations depended on whether or not the soil was frozen. Runoff samples were separated into water and sedi- ment phases by filtration. It appeared that nitrogen and chloride amounts of both phases were related to time of year and fertilizer practices. During the summer the high- est contents were found in runoff after fertilization, and decreased thereafter. Low amounts were found during the winter when the soil was frozen. Warming of the soil in early spring prior to fertilization appeared to cause increases in nitrogen and chloride content of the runoff as compared to winter data. Phosphate concentrations in sediment and water phases of runoff were related to both fertilizer applica- tion and sediment content in grams per liter. Phosphate increased as sediment increased except for the runoffs of late spring prior to fertilization. Contents were highest in the first few summer runoffs after fertilizer applica- tion. Soil core data showed downward movement of nitrate nitrogen and chloride through the profile. The 1974 data showed leaching after fertilization followed by an upward movement of nitrate nitrogen and chloride during the first month. This appeared to be a capillarity effect. Leaching occurred during the rest of the season. Robert Kingsley Hubbard There was horizontal movement of chloride, nitrate nitrogen, and phosphate from upper sloping areas of the watersheds to the flume approach areas. The amount of nutrient moved depended on how recently fertilizer had been applied and runoff magnitude. Kjeldahl data showed high nitrogen in the flat flume approach areas; clear evidence of movement of nitrogen downlepe over time in surface run- off. Mass balance calculations were made of percent applied nutrient lost in surface runoff. Nitrogen losses in runoff were equivalent to 1.5 to 3.0 percent of input fertilizer nitrogen. Losses of phosphorus were equivalent to 0.3 percent of applied fertilizer phosphorus on both watersheds. Nitrogen was lost mainly in organic forms and phosphorus was lost mainly in the sediment phase of sur- face runoff. A comparison between a watershed profile and a virgin profile showed evener and deeper distribution of phosphorus in the virgin soil. Total phosphorus and phos- phate were higher in the cultivated soil, but percent organic matter was lower. THE VERTICAL AND HORIZONTAL REDISTRIBUTION OF NITROGEN, CHLORIDE, AND PHOSPHORUS BY PRECIPITATION AND SURFACE RUNOFF ON TWO SMALL WATERSHEDS BY Robert Kingsley Hubbard A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Department of Crop and Soil Sciences 1975 To My Wife ii ACKNOWLEDGMENTS The author is grateful to Dr. A. E. Erickson for guidance and for patient help in preparation of this thesis. Thanks are given to Drs. B. G. Ellis, E. H. Kidder, and A. R. Wolcott for correcting the thesis and serving on the guidance committee. The author thanks Ms. Elizabeth Shields and staff of the Soil Chemistry Laboratory for assistance and analyti- cal work. Assistance in laboratory analyses and encourage- ment by my wife Rae are greatly appreciated. Finally, the author expresses appreciation to Michi- gan State University, and the Southeast Environmental Research Laboratory of the Environmental Protection Agency, Athens, Georgia, for financial assistance during the Master's program. iii TABLE OF CONTENTS Page LIST OF TABLES 0 0 0 0 0 0 0 0 9 0 . 0 Vi LIST OF FIGURES . . . . . . . . . . . . Viii INTRODUCTION . . . . . . . . . . . . . 1 LITERATURE REVIEW . . . . . . . . . . . 4 Nitrogen . . . . . . . . . . . . 4 Nitrogen in the Soil . . . . . . . 4 Addition of Nitrogen to Soil . . . . . 4 The Nitrogen Cycle . . . . . . . . 6 Movement of Nitrate Nitrogen . . . . . 8 Phosphorus . . . . . . . . . . . 12 Chloride . . . . . . . . . . . . 18 Watersheds . . . . . . . . . . . 20 Watershed Models . . . . . . . 20 Movement of Agricultural Chemicals on Watersheds . . . . . . . . . . 23 MATERIALS AND METHODS . . . . . . . . . . 28 Watersheds Site . . . . . . . . . . 28 Field Operations . . . . . . . . . 28 Soil Sampling Sites . . . . . . . . 33 Soil Sampling Methods . . . . . . . 36 Collection of Runoff Samples . . . . . 39 Event and Weather Monitoring Equipment . . 40 Storage and Preparation of Samples . . . 41 Determination of Sediment Content . . . . 42 Chemical Analyses . . . . . . . . . 42 Nitrate . . . . . . . . . . . . 43 Ammonia . . . . . . . . . . . . 45 Total Nitrogen . . . . . . . . . 45 Chloride . . . . . . . . . . . 46 Phosphate . . . . . . . . . . . 46 Total Phosphorus and Carbon . . . . . 47 iv Page RESULTS AND DISCUSSION . . . . . . . . . 48 Hydrologic Events . . . . . 48 Factors Influencing Runoff Magnitude . . . 52 Runoff Samples . . . . . . . . . . 54 Sediment Content . . . . . . . . 54 Nutrient Content of Water Phase . . . . 55 Nutrient Content of Sediment Phase . . . 60 Soil Samples . . . . . . . . . 62 Sampling Variability . . . . . . . 62 Nutrient Content in 1973 . . . . . . 80 Nutrient Content in 1974 . . . . . . 82 Mass Balance . . . . . . . . . . . 89 Soil Phosphorus: Comparison Between Virgin and Cultivated Watershed Soils . . . . 92 CONCLUSIONS . . . . . . . . . . . . . 95 REFERENCES 0 O O O O O O I O O O O O 99 APPENDIX 0 O O O O O O O O O O O O O 104 Table l. 10. ll. 12. 13. 14. LIST OF TABLES Total Monthly Precipitation from June, 1973, through Auguts, 1974 . . . . . ,Runoff Events with Rainfall Data from June, 1973, through August, 1974 . . . . . Maximum Summer Runoffs and Related Factors Average Nutrient Content (ppm) and Sediment Content (g/l) of Runoff Water on East and West Watersheds . . . . . . . . . Average Nutrient Content (Ppm) of Runoff Sediment and Sediment Content (g/l) of Run- off Water on East and West Watersheds . . Soil Cores, East Watershed, 6-73 to 5-74 (ppm NO3/N) . . . . . . . . . . Soil Cores, West Watershed, 6-73 to 5-74 (ppm NO3-N) o o o o o o o o o 0 Soil Cores, East Watershed, 6-73 to 5-74 (ppm C1) . . . . . . . . . . . Soil Cores, West Watershed, 6-73 to 5-74 (ppm Cl) . . . . . . . . . . . Soil Cores, East Watershed, 6-73 to 5-74 (ppm PO4-P) o o o o o o o o o 0 Soil Cores, West Watershed, 6-73 to 5-74 (ppm PO4-P) o o o o o o o o o 0 Soil Cores, E. Watershed, 5-74 to 9-74 (ppm NO3-N) o o o o o o o o o 0 Soil Cores, W. Watershed, 5-74 to 9-74 (ppm NO3-N) . . . . . . . . . . Soil Cores, E. Watershed, 5-74 to 9-74 (ppm NH4-N) . . . . . . . . . . vi Page 49 50 51 56 61 63 64 65 66 67 68 69 70 71 TABLE 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. Soil Cores, W. Watershed, 5-74 to 9-74 (PPm NH4-N) . . . . . . . . . Soil Cores, E. Watershed, 5-74 to 9-74 (ppm K;N) . . . . . . . . . . . Soil Cores, W. Watershed, 5-74 to 9-74 (ppm K;N) . . . . . . . . Soil Cores, E. Watershed, 5-74 to 9-74 '(ppm Cl) . . . . . . . . . . . Soil Cores, W. Watershed, 5-74 to 9-74 (ppm Cl) . . . . . . . . . . . Soil Cores, E. Watershed, 5-74 to 9-74 (ppm PO4-P) . . . . . . . . . . Soil Cores, W. Watershed, 5-74 to 9-74 (ppm PO4-P) . . . . . . . . . . Nitrate Nitrogen, Chloride, and PhOSphate PhOSphorus Content in Parts per Million of Five Composited Soil Samples per Depth for Variability Studies . . . . . . . . Total Sediment Lost from the Watersheds in Runoff (6-73 to 8-74) . . . . . . . Total NO3-N, NH4-N, KjN, and PO4-P Lost from the Watersheds in Water and Sediment Phases Of Runoff (6-73 to 8-74) . . . . . . Comparison of Total Phosphorus (ppm), Phos- phate Phosphorus (ppm) and Percent Organic Matter between Cultivated Watershed Soil and Virgin Soil . . . . . . . . vii Page 72 73 74 75 76 77 78 79 89 91 93 Figure 1. 10. LIST OF FIGURES Movement of NO -N in a fallowed Plain- field sand over an 8-month period follow- ing the application of N as NH4NO3 . . . The effect of soil type on the distribution of P32 with leaching with high P applica- tion . . . . . . . . . . . . . Compartments of a model for chemical move- ment in watersheds . . . . . . . . . Soil map of the watersheds . . . . . . Contour map of the watersheds . . . . 1973 soil sampling areas . . . . . . . 1974 soil sampling areas . . . . . . . Kjeldahl nitrogen content of the 0-1 cm depths of east and west watersheds by date . Kjeldahl nitrogen content of the l-2.5.cm depths of east and west watersheds by date . Phosphate phosphorus content of the 0-2.5.cm depths of the east watershed by date . . . viii Page 11 17 21 29 31 34 35 85 86 88 INTRODUCTION Within the past century, American life has changed from a predominantly agrarian society barely able to meet its food and fiber needs, to a society fed and clothed as no other has been. Production efficiency has so improved that now only about 10% of the population grows the food for the rest of the nation. Although non-agricultural developments have played essential roles in the tremendous increases in agricultural production, adaptive research by agronomists has been of equal or greater significance. One third to one half of our present agricultural production depends on fertilizers. Research on plant nutrients and their movements is of tremendous significance. Historically, the main concern with nutrients has been to provide correct kinds and quantities for optimum plant growth. Much of the first agricultural research concerned quantities of naturally occurring nutrients in the soil and their availability to plants. As chemical fertilizers became increasingly available, research shifted into studies of application rates and studies on fertilizer movement within the soil as related to crop production. The 1954 study by Lawton and Vomicil on dissolution and migration of phosphorus from granular superphosphate is a good example of the concern with fertilizer movement in the soil. Recent concern with fertilizers has shifted greatly into the area of pollution. As nitrates are a suspected health hazard, there is concern with movement into ground or surface waters. Phosphate is the prime limiting growth factor for algae in open bodies of water, so there is concern with pollution from phosphate. Present research on movement of fertilizers in and over soils con- cerns both plant nutrition and agricultural pollution. Experimental watersheds with flumes for capturing and measuring surface runoff are ideal for studying many natural plant and soil processes and their relationships. Many experimental watersheds were originally conceived and built to study soil erosion. They were used to establish long time records of naturally occurring hydrologic events and soil erosion. Since there is less concern with soil erosion studies in America today, many recent researchers have used watersheds to study movement of agricultural chemicals in surface water. Recent watershed research on movement of agricul- tural chemicals has been primarily concerned with the move- ment of nitrates and phosphates in the surface runoff. Nitrogen and phosphorus losses in surface runoff were studied intensively by Schuman, Burwell, Piest, and Spomer (1973). They related different crops and fertilizer rates to amounts of fertilizer lost in surface runoff. Similarly, other investigators have compared the effects of tillage methods or different methods of soil management on surface runoff losses of nitrogen and phosphorus (Klausner, Zwerman, and Ellis, 1974; Romkens, Nelson, and Mannering, 1973). Unique to this study is concern with both loss of nutrients in surface runoff and vertical and horizontal redistribution of the nutrients on the watershed. Also unique is the collection and analyses of winter runoff. The objectives are: 1. To determine loss of nitrates and phosphates in surface runoff throughout a one and one half year period with specific fertilizer practices in relation to hydrologic events. 2. To determine downward leaching of nitrates, ammonia, and phOSphates in the profile and their relation with corresponding hydrologic events. 3. To determine lateral redistribution of nitrates and phosphates down the watershed after runoff events. 4. To compare levels of current phorphorus with virgin soil and relate them to past fertilizer practices. This study should provide a clearer picture of movements of both residual and applied fertilizers through, over, and off natural watersheds with naturally occurring rain and snow. Comparisons of phosphorus levels between virgin and cultivated soils should give a clearer idea of the effects of fertilization and cropping over time. LITERATURE REVIEW Nitrogen Nitrogen in the Soil Nitrogen found in the soil can generally be classi- fied as inorganic or organic. The inorganic forms include NH4+, N037, NOz-, N20, NO, and elemental nitrogen, which is inert except for its utilization by Rhizobia (Tisdale and Nelson, 1968). The organic forms of soil nitrogen occur as consolidated amino acids or proteins, free amino acids, amino sugars, and other complex compounds (Tisdale, §t_al., 1968). Native soil N consists primarily of the organic forms. A recent nitrogen characterization of Brenton silt loam for example, showed an average of 1.3% N *1. in available mineral forms (N037 plus exchangeable NH4 5.0% fixed NH4+, and 93.8% organic forms with the largest single amount occurring as amino acid - N (33.7%) (Allen, Stevenson, and Kurtz, 1973). Addition of Nitrogen to Soil Nitrogen is added to the soil naturally or with the aid of man. Nitrogen compounds in the atmosphere are returned to earth in rainfall in the form of ammonia, nitrate, nitrite, nitrous oxide and in organic combinations. The ammonia comes largely from industrial sites, whereas nitrate is thought to form during electrical discharges, from industrial waste gases, or from the soil. Total amount of fixed nitrogen brought down in rainfall has been variously estimated to range between 1.12 and 56.00 kg/ha annually, depending on location (Tisdale et_al,,l968). The total amount of N appearing annually in rainfall can be greater than that removed in surface runoff (Klausner, §5L5§1., 1974). For centuries man provided nitrogen to his crOps by the use of legumes in crop rotations and the applica- tion of animal manures. Legumes add nitrogen to the soil due to Rhizobia and other microorganisms living symbioti- cally on their roots and fixing atmospheric N. Nitrogen added in animal manures is primarily in organic forms. Over the past two decades, nitrogen fertilization practices have changed from addition of animal manures or use of legumes to addition of nitrogen in chemical form. Most of the chemical sources of nitrogen are ammonia deri- vatives. The following ammoniacal compounds are used as sources of fertilizer nitrogen: anhydrous ammonia, NH3 (82% N); anhydrous ammonia-sulfur (74% N, 10% S); aqua ammonia and other nitrogen salts (24-49% N); ammonium nitrate with lime, ANL (20.5% N); ammonium nitrate-sulfate (30% N, 5% S); ammonium sulfate (20.5% N, 23.4% S); monoammonium phosphate, MAP (11% N, 21% P); diammonium phosphate, DAP (16-21% N, 21-23% P); ammonium phosphate- sulfate (16% N, 9% P, 15% S); ammonium chloride (26% N); urea (45% N); urea-sulfur (40% N, 10% S); and urea phos- phates (Tisdale et al., 1968). The Nitrogen Cycle The nitrogen released from organic reserves and the fate of applied nitrogen fertilizer is dependent on the balance existing between factors affecting nitrogen mineral- ization, immobilization, and losses from the soil. Nitro- gen mineralization is the conversion of organic nitrogen to a mineral (NH4+, N02- zation is the conversion of inorganic or mineral nitrogen , N03-) form. Nitrogen immobili- to the organic form. Losses of nitrogen from soils include crop removal, denitrification, and leaching. Nitrogen is needed by heterotrophic soil micro- organisms for the decomposition of organic matter. When organic materials with a C:N ratio greater than 30 are added to soils, there is immobilization of soil nitrogen during the initial decomposition process (Tisdale et al., 1968). The mineralization of organic compounds consists of three reactions: aminization, ammonification, and nitrification. Aminization follows the formula: proteins ———+ R-NH2 + CO2 + energy + other products Ammonification follows the formula: R-NH2 + HOH ———+ NH3 + R-OH + energy Nitrification is a biological oxidation of ammonia to nitrate. It is a two step process following the formula: + - + ZNH4 + 302 ———+ 2N02 + H20 + 4H Conversion of ammonia to nitrite is brought about largely by the obligate autotrophic bacteria Nitrosomonas, and conversion from nitrite to nitrate is brought about by the obligate autotrophic bacteria Nitrobacter (Tisdale g£;gl., 1968). All nitrogen fertilizers, regardless of the form applied, will ultimately be changed to the nitrate form of nitrogen (Edwards, Fischbach, and Young, 1972). Denitrification occurs in waterlogged soils where anaerobic decomposition takes place and oxygen is excluded. Species of the genera Pseudomonas, Micrococcus, Achromo- bacter, and Bacillus obtain their oxygen from nitrates and nitrites with the accompanying release of nitrogen and nitrous oxide. Movement of Nitrate Nitrogen Nitrate nitrogen is completely mobile in soils and within limits moves largely with the soil water. With rainfall or irrigation, nitrate is leached out of the upper into the lower horizons of the soil. During dry weather and when capillary movement of water is possible there is an upward movement of the ion, related to the upward movement of water. There are two main concerns with nitrate leaching. One is the loss of nitrOgen for crOp use, and the second is concern with contamination of ground waters. The only suspected health hazard from fertilizer is nitrate (Kurtz, 1970). There have been numerous studies on nitrate leach- ing. In most soils nitrates move at an equal rate with downward moving water (Kurtz and Melsted, 1973). Articles by Stewart (1970) and Pratt, Jones, and Hunsaker (1972) assume that N03- moves at the same rate as water and that adsorption is not a major consideration. Shaw (1962) states that there is little difference in the amount of rain required to remove nitrate from surface layers of light or heavy soils, but heavy and continuous rain is requiredtx>remove nitrate completely from either type of soil. Wallace and Smith (1954) observed that when nitrate was added to the surface of a 61 cm column of loam soil at field capacity, approximately 25.4 cm of water was required to leach 50% of the added nitrogen from the column, and 40.6 cm to remove 98% of the nitrogen. Wetselaar (1961) states that during dry periods there may occur appreciable reverse movement of nitrate, but this upward movement is usually confined to the upper 30.5 to 45.7 cm of soil. Sommerfeldt and Smith (1973) studied the downward movement of NO3--N in dryland soils under native grass and concluded that with good management, fertilizer N on grass- land soils is not an important contributor to groundwater pollution. Downward movement of NO3--N in the soil under 'native grass fertilized in 1961 at rates up to 976 kg/ha reached a depth of 180 cm by 1969. Depth of penetration of NO3--N with natural rainfall varied with the kind of vegetation growing on the dryland, being greatest under native grass. Under irrigation, the differences in the amount of NO --N leached were attributed to management 3 and the kind of crop growing on the land. Edwards et_al. (1972) concluded from irrigation studies that nitrates move essentially with the wetting front when soil is initially air dry, but do not move at the same rate as the water when the soil is initially saturated. They found that with a properly designed and managed irrigation system, little or no movement of 10 nitrates outside the root zone occurs. Cassel (1971) com- pared downward movement of chlorides and nitrates between a plot covered to prevent exchange of water at the soil surface and a bare plot subjected to prevailing environ- mental conditions. Nitrate and chloride ions leached to a greater soil depth per unit of applied irrigation water on the covered plots where there was no evaporation. Lin- ville and Smith (1971) traced nitrate nitrogen movement on corn plots after repeated nitrogen fertilization. Nitrate accumulation and losses by leaching and/or denitrification were found to be related to soil texture. The coarser the texture and the greater the large pore space, the greater the mean downward movement of nitrates under the influence of a given quantity of added water (Tisdale et_gl., 1968). Nitrates can thus move quickly through sandy soils. Figure 1, from data of Olsen, Hensler, Attoe, Witzel, and Peterson (1970) shows movement of NO3-N in a fallowed Plainfield sand over an 8 month period following the application of N as NH4N03. N03 is expected to leach in similar manner on the sandy soils in this study. Nitrates can also be lost through movement in sur- face run-off. A discussion of this phenomenon is included in the Watersheds section of the literature review. 11 .Aonma ..Hm um cmmaov .mmmH .oa Hanna can moaa .mm Amnouoo cmmzumn goaunuamaomnm no so ma can mead .mm Honouoo can m Hmafimummm cmm3pmn aflmu no So «H .mmma .m HmQEmummm can A umsm5¢ qmmspmn aoflummflnufl no can“ mo EU om ©m>wmomu mmum uoam was .mmaa .H unsmaa co moZVBz mm 2 mo coaunoaamam msu mcfisoaaom poaumm nuGOEIm cm Hm>o pawn pamflmcflmam pmsodamm m ca zlmoz mo usme>ozll.H musmflm 1 L 9:9. N. «o l I L n;\ax mmmx. no . mn\ax ~__ . mc\mx ennui l m£\mx N__I. . mam. l , mam. ma taaoaoa mam. ar\ax ammT. .o. __ra< .m toaeoaamm m. a. m. o m. a. m a mN ON m. a. m aaa .z-maz __0m oom cam om— 0N— om 'wv ‘undea 110$ 12 Phosphorus A variety of studies have been done on phosphorus diffusion in soils. In Michigan, Lawton gt_al. (1954) studied the dissolution and migration of phosphorus from granular superphosphate. At field capacity 50 to 80% of water soluble phosphorus moved out of the granules within 24 hours, and even in soils as low as 2 to 4% moisture, 20 to 50% moved from the granule into the soil in one day. Maximum movement was about 2.5 cm at soil moistures approxi- mating field capacity and most of the movement occurred within one week. Bouldin and Black (1954) investigated the validity of activity measurements as estimates of phosphorus diffu- sion from P32 tagged phosphate sources. Significant changes in the apparent specific activity of diffusing phosphorus were found, but could be accounted for by assuming exchange between diffusing P32 and native soil P31. The overall picture of phosphorus diffusion obtained from activity measurements was not substantially different from that obtained by total phosphorus analysis. A study by Phillips, Place, and Brown (1968) meas- ured self-diffusion coefficients of P32 in kaolinite clay, montmorillonite clay, illite clay, Dundee silt loam soil, and Sharkey clay soil. Concentrated superphosphate was added to each clay or soil at the rates of 10,20,40,80,160 l3 and 320 ppm. An interface between tagged and untagged clays and soils was created for each sample and the sam- ples allowed to equilibrate. The experimental distribu- tions obtained for the clays and soils were used to calcu- late self-diffusion coefficients. Self-diffusion coefficients and phosphorus rates of each clay and soil were found to be linearly and positively correlated. Williams (1970) investigated the reaction of surface-applied superphosphate with soil. Phosphate mov- ing into moist soil from particles of surface-applied super- phosphate was found to penetrate a hemispherical zone beneath the particle. Size of the zone and distribution of phosphate through it were governed by the phosphate sorption capacity of the soil, size of the particle, and soil moisture. Leaching influenced the movement of phos- phorus by distorting the hemispherical distribution of phOSphate beneath superphosphate particles. The result was deeper penetration of phOSphate below the particles and smaller horizontal movement away from them. Vaidyanathan and Nye (1971) also worked with diffu- sion coefficients of phosphorus. By following the efflux of phOSphate into a limited volume of well-stirred CaCl2 solution, of the same ionic composition as the soil-pore solution except for lower initial phosphate concentration, the counter-diffusion of phosphate against chloride was 14 measured. By varying this phosphate concentration, effec- tive diffusion coefficients over a wide range of depletion were measured. Their experiment was designed to test the tentative conclusion that concentration-dependent diffusion coefficients of phosphate can most readily be calculated from the desorption isotherm of soil phosphate. Hashimoto and Lehr (1973) surface applied ammonium ortho-, pyro-, tripoly-, tetrapoly-, and long-chain poly- phosphates and cyclic ammonium tri- and tetrametaphos- phates to soil columns. Measurements were made of the gross mobilities in soil in an attempt to determine the effect of chain length and structural configuration of mobility. General features of the distribution patterns were found to establish by the first week, after which solu- ble P moved much more slowly and the amount of immobilized P increased slowly. Total distance of movement and dis- tribution patterns of water-soluble P were similar for all the phosphates tested, but the polyphosphates differed markedly in the degree of immobilization and differed sig- nificantly in the positions of maximum retention of P in the soil columns. Phosphate is rarely nmwed more than a few centi- meters from the point of application (Kurtz, 1970). Leach- ing of phosphate on soils of moderate textures is very small. However, for soils that are very sandy and contain 15 little silt or clay, leaching of any element can be appre- ciable. The sand fraction is essentially inert and does not combine with even the "immobile" ions to prevent their movement in soil water. Downward movement of phosphate even on sandy soil is likely to stop in the lower soil hori- zons which tend to have more clay (Parker, 1972). Humphreys and Pritchett (1971) investigated phos- phorus adsorption and movement in some sandy forest soils. Soils were examined seven to eleven years after application of rock or superphosphate to locate the applied phosphates. Little or no residual P from superphosphate remained in the top 20 cm of soils with no P sorption or buffering capacity. Almost all of the superphosphate remained in an available form in the rooting zone in soils with a low P sorption and buffering capacity. In a soil with a high P sorption and buffering capacity most of the added P was retained in the surface horizon in a poorly available form. Logan and McLean (1973a and 1973b) conducted column experiments on movement of P32 in three soils of varying chemical and physical properties. Two separate papers were written concerning their results; "Nature of Phosphorus Retention and Adsorption with Depth in Soil Columns" (1973a), and "Effects of PhOSphorus Application Rate, Soil Proper- 32 ties, and Leaching Mode on P Movement in Soil Columns" (1973b). In the first paper, major effects on P movement 16 were due to soil differences and P application rates. Leaching was greatest in the sandy loam soil. In the soils studied, the percentage of NH4Cl-extractable P decreased rapidly in the initial 2 cm depth and then remained fairly constant. The percentage of NaOH-extractable P increased as that of NH4F-extractable P decreased and that of H2804- extractable P increased gradually with depth. (In general, NH4C1 and NH F-extractable P are forms more available to 4 plants, and NaOH andfifflxfextractable P are less available 2 forms.) The second article relates application rate, soil properties, and leaching mode to movement. Leaching of P increased with P application rate and intensity of leaching. Constant head leaching resulted in greater movement of P32 out of the surface layer and greater accumulation in the leachate than intermittent leaching. Significant amounts of P were recovered in the leachate only with sandy loam soil and at the highest P application rate. Figure 2 shows 32 with the effect of soil type on the distribution of P leaching. Clearly phosphates can leach in sandy soils. The primary method of loss of phosphorus from agri- cultural fields is soil erosion. Since nearly all phos- phate is bound securely is the soil, erosion presents the greatest potential for loss of phosphate. l7 .Anm5ma ..Hm um comedy .cowpmoflammm m now: Spa? mcwnomma sufl3 mmm mo coflusnwuumflp wan so mmhu HHom mo Hommmm O£BII.N musmflm A__0m m\mmnv managamoza no_onm_ mmm mo cowumtucou:0u coco coo: ooow pom. com. oou. com com com o 1‘4 a q “ w 4 . .m— . N. m>mp OM\Eu on 229. 32 m m m:_:umo_ pom; ucmuchu .m U- m, M w m .. flame. u__m. oc>OEmmOx gill! Emo_ >pcmm common: I o 'lllnlll'll‘lillll | 18 Chloride The best way to trace the movement of soil water is to dissolve something in it that moves easily and can be easily traced. The chloride ion is usually considered as the most nearly ideal tracer, although negative or positive adsorption may be encountered to a limited extent in some soils (Kurtz §t_gl., 1973). Comparisons of chlor- ide with tritium as ground water tracers have shown that at high flow velocities (2.0 cm/hr) both move simultane- ously through both glass beads and clay, but that at low flow velocities they move at different rates (Biggar and Nielsen, 1962). Corey and Fenimore (1968) compared chlor- ide and tritium as groundwater tracers on acid kaolinitic soil and concluded that chloride and other negatively charged ions have limited usefulness as water tracers in acid soils. For most situations however, chloride is an excellent tracer of groundwater movement. In addition to being useful for tracing ground- water movement, chloride is an excellent indicator of how nitrate should move. In most soils, they appear to move at an equal rate with each other and with the water. Fulcher and Tyner (1959) and Cassel (1971) have presented data indicating equivalent rates of movement of NO3 and Cl . Simultaneous transport of chloride and water dur- ing infiltration was investigated by Kirda, Nielsen, and l9 Biggar (1973). It was determined that initial soil water content did not influence the depth of chloride displace- ment for a given quantity of water infiltrated; whereas keeping the water content at the soil surface below satura- tion resulted in a deeper and more complete displacement of chloride. A numerical method for predicting chloride distribution was outlined and was found to give satisfactory agreement with experimental data provided the predicted water content distributions were sufficiently accurate. Chloride diffusivities in medium and fine-textured soils at moisture tensions from 1/3 to 15 atmospheres were measured by Porter, Kemper, Jackson, and Stewart (1960). Calcium and calcium-sodium soil systems were studied. Effective diffusivity of chloride was divided by the dif- fusivity of chloride in bulk water to obtain a transmission factor. In the Ca-saturated systems, the transmission factors of the different soil textures used were essentially straight-line functions of the moisture contents. Trans- mission coefficients in the sodium systems were similar. Using chloride Smith (1972) investigated the phe- nomenon of anions moving through soil faster than the average velocity of the water molecules present. The theory behind such movement is that the greater average velocity of the anions is due to the fact that they are excluded from the immediate vicinity of negatively charged soil 20 particles where the water is relatively immobile and from narrow pores where solution velocities are slow. Using 15 widely varying surface soils and 0.01N CaClZ, he found that chloride moved through the soils 1.04 to 1.67 times faster than it would if it had been associated uniformly with all the soil water. Results of his study support the view that anion.exclusion can be an important factor contributing to loss of anions from soil. The ability of chloride to trace water movement and predict nitrate movement makes it quite important for watershed studies. Determination of chloride movements through soil and in surface runoff was thus essential in this study. Watersheds Watershed Models In tracing movement of an agricultural chemical on a watershed eight compartments need to be considered. These are: the plant, surface water, surface soil, inter- mediate water, intermediate soil, groundwater, runoff, and erosion. These are shown in Figure 3. Adsorption, degrada- tion, and volatilization are processes which affect agricul- tural chemicals while within these compartments, and may cause losses of the chemical separate from the effects of a hydrologic event. 21 A.m>ma .muwumv .mpwnmuwums cw ucmfim>oE HMOflfimao mom Hopes m mo mucwfiuumm50011.m musmflm Loumzccnotu m:_;om04 me m Loam: _ /. oum_poetmuc_ emaczm o.\\. co.umtu_.mc_ co_motm\\\\ amw Loam . . T1 )hMWH \ 3 co_motm T .LVV Gown—Lam \ a_t yam—m z_..::o / / / // // o / . . l O_Q . ~ N i . \ II x «.0 31 Figure 5.--Contour map of the watersheds. 32 I! .2! .Ic.§ int-1:6 811: 588 It... i... .2: .8 i... .5: 3:: waldo 5552.5 ~55 52qu 5mg 30.23%. 28.530»: 23.20.! mouzmcufii 35>. .53 ./ /I 3. / .. .. .1 /, l i /. I. e a «9 /l/ .8 Nu /, ... ... .\ to A / a. .9/ -/ / a - lk/ - s. -e/ 33 In 1973 soybeans (Glycine max, var. Hark) were grown on both east and west watersheds. Fertilization consisted of broadcasting KCl and sidedressing basic fertilizer. One hundred twelve kg/ha of 60% KCl was broadcast through a grain drill with hoses removed. Two hundred twenty-four kg/ha of 12-12-12 was placed 3.8 cm to the side and 3.8 cm below the soybean seed. Corn (Zea mays, var. Pioneer 3780) was grown on the east watershed in 1974, and soybeans (var. Hark) on the west. One hundred seven cm rows were used and the planter was set to deliver 54 to 59 thousand seeds per hectare for each crop. Basic fertilizer was broadcast on both watersheds and tilled in to a 7.6 cm depth, using a horizontal tool bar agitator. Calculated applications of the broadcast fertilizer based on actual deliveries over the estimated area were 68.4 kg/ha N, 93.0 kg/ha P, and 172.6 kg/ha K. An additional 130.0 kg/ha N was sidedressed on the corn only. Soil Sampling Sites Figures 6 and 7 respectively show the soil sampling areas for 1973 and 1974. Four sampling areas per water- shed were used the summer and fall of 1973. The four areas on each watershed were: 1. flume approach (0 to 2%); 2. lower slopes (2 to 4%); 4 3 .mmmH< mGHHQEmm HHom mnmall.m musmflm :nummm_ mucoEmmm m:__dsmm momzmmwh<3 :mz . / .5. £13 A ,5 _ o . .38 m ... .1 ... mm. .38 meu : mmt< aw-. mot< w m m «N. : mN. m .x. .x. m mot< m __. m 3. N . ... ... i. N 8. _ ... S. _ . N ... ... m .1 mutmuoo: “cosmom . mot< x m m " mot< murmuoo: ucoEmom nooov pocmtmumz ummm /. w / W Anoov posmtoumz umoz IIIIII — trot .IllllllNlllll/o ... ............ .. . .. 82 .. pa. coo — u u u. lllllllll .- .4; . x mot< m m m m w H” M II\ n. — u. ”p w u / mmtmHm m>mp cm>wm samm msoH>mum ammo o>flm swam m90w>mum mamo MDOH swam msoH>mum m>mp conga swam msofl>oum mama 03» swam Q mDoH>wum mop mco Gamma cm.o ummz pmo.o 0m 05.0 ma.m m>.v mm.v oa.m em.o ummm vhuhmum 00m.o mv.o ummz Q0m.0 mm mH.o mm.m oa.o mm.n va.m m>.o ummm vhumaum mmm.a No.0 ummz mah.o ma mm.o mm.> mm.> mm.h Ho.o ummm vhumlh mo.o umma nam.o mm av.o mm.a om.m om.m 0H.m ma.o ummm vnnmnh omo.H omo.o has 0 omm.o oNH mv.o Hm.m om.m hm.¢ oa.o Ho.o ummm vunmalm Eu wou5:«z Eu so HQ\EU EU m>m co>m 0:5 , a m unease no on x no unnum 56m H38. 55 S 5... m 5... m 8323: 6333...: 38 m50w>oum CH uumum umuwm cflmm Cu uofium CHMm wwocdm swam Hmuos msoscfiucou mo coflumudo >uwmcmucH Hammcamm EDEmez .MHOUUflh COUGHQM UCM mmwogm .Hmwcuflam ggflufiMZIlom 8&9 52 Factors Influencing Runoff Magnitude Table 3 shows information relating to the causes of summer runoff on the watersheds. Since all runoffs in summer, 1973, were of trace magnitude, only runoff events in July and August, 1974, are shown. From Table 3 the most important factors causing runoff were rainfall intens- ity and duration of continuous rain after the start of runoff. The maximum two minute rainfall intensity occurred on 8-13-74, the date of maximum runoff. On this date the longest continuous rainfall occurred after the start of runoff, excluding 5-16-74. The watersheds were plowed on 5-14-74 so loose soil structure was an important considera- tion in relation to runoff magnitude on 5-16-74. Total rainfall on the event date was related to runoff magnitude. Total precipitation of 3.23 cm on 8-13- 74 and 3.18 cm on 8-27-74 led to much greater runoffs on those dates than total rains of 1.35 cm on 7-2-74 and 0.89 on 7-9—74. Rain prior to the start of runoff on the event date might be related to runoff magnitude in 1974. Com- parison between the events of 7-2-74 and 8-27-74 showed much greater runoff on 8-27-74. These dates have identi- cal two minute rainfall intensities, and similar duration of raihfall after the start of runoff, but more rainfall prior to the start of runoff on 8-27-74. The five and ten minute rainfall intensities on 8-27-74, however, were 53 larger than those of 7-2-74 so greater runoff cannot be attributed only to greater rainfall prior to runoff. The total rainfall in the previous seven days, and thus the moisture content of the watersheds prior to run- off, clearly (LRi not have the same importance in runoff magnitude that rainfall intensity and duration had in 1974.. Maximum rainfalls prior to the event date occurred on 7-2-74 and 7—9—74, the dates with minimum runoffs in Table 3. One factor which must be considered in analyzing runoff magnitude is the infiltration rate as influenced by the structure and bulk density of the soil surface. The data for 5—16-74 in Table 3 indicate that larger magnitudes of runoff should have occurred on that date. Rainfall intensity was high, total rainfall was high, rainfall in the previous week and thus soil moisture was high, and the duration of rain after the start of runoff was 120 minutes. The plow layer on 5-16-74 was loose and porous due to plowing on 5-14-74. Consequently, runoff was small. It was observed in both 1973 and 1974 that a compact sur- face structure conducive to runoff forms only after con- siderable time and rainfall, usually including several events that have the intensity to cause runoff but do not. This structure has usually formed by late July or August. The high runoff magnitudes of August, 1974, reflect that the surface soil had become hard and compact. 54 Runoff magnitudes during the winter depended pri- marily on amount of precipitation. The soil generally was frozen, or if thawed, quite saturated. Much lower intensity rains caused runoff during the winter period. The majority of winter runoffs were caused by snowmelt, and magnitude depended on amount of snow on the watershed and the rise in temperatures above 32 F. Runoff Samples Sediment Content Table 4 includes the average sediment content (g/l) of runoff samples for the period 6-16-73 through 8-27-74. The data show relatively low sediment contents for the sum- mer of 1973 with the exception of one high sediment sample on 7-2-73. Winter runoff was quite low in sediment except for the runoff of l-26-74. This runoff was caused by rain- fall on thawed ground in contrast to snowmelt over frozen ground on the other winter dates. The runoffs of 4-1-74 and 4—3-74 show increased sediment due to partially thawed and thawed soil respectively. Runoffs of summer 1974 were considerably higher in sediment than summer 1973 due to greater rainfall and runoff intensities. The higher sedi- ment contents on 5-16-74, 7-2-74, and 7-9-74, as compared to 8-13-74 and 8-27-74, were due to the loose surface soil structure from plowing on 5-l4-74. 55 Nutrient Content of Water Phase Table 4 also shows the average nutrient content (ppm) of the water phase of the runoff samples. Nitrate nitrogen ranged from 0.3 to 6.4 ppm, NH4/N from not detect- able to 3.8 ppm, KjN/N from 0.8 to 4.9 ppm, Cl from 2.4 to 25.8 ppm, PO4/P from 0.02 to 1.28 ppm, and total P from 0.05 to 1.32 ppm. The only NO3/N data of the summer water phase for 1973 show relatively high amounts of NO3/N. These values are from 8-9-73, the largest runoff from a summer with very little runoff. High NOB/N content of runoff on this date reflects little removal of NO3/N in the previous runoffs of the summer of 1973. Nitrate nitrogen content of the runoff water phase is quite low during winter 1973-1974. An increase on the east watershed on 5-11—74 (1.8 ppm) reflects the warmer soil and the release of nitrate as part of the nitrogen cycle. The high NO3/N of the runoff water phases on 5-29-74 (2.1 ppm), 7-2-74 (4.0, 4.8 ppm), and 7-9-74 (8.8, 6.4 ppm) are directly attributable to nitrogen fertiliza- tion on 5-20-74. The increase in NO3/N between 5-29-74 (2.1 ppm) and 7-9-74 (8.8, 6.4 ppm) represents the conver- sion of NH4/N to NO3/N, and the mineralization of organic nitrogen. .wanmuomumv uoz oz .mommamcm ~00 mHmEMm ucmaoamwzmcHIII .momxamcm Mom mandaflm>m mamewm 0:0 >Hco« 565 00.N Nv.m 00.0 mv.0 v.H 0.H 0.0 0.0 0.0 0.0 thhNI0 0H.m 00.0 00.0 00.0 m0.o 00.0 0.0 0.0 0.N 0.N 0.0 0.0 0.H 0.0 thmaI0 «ON.MH «om.m mn.0 00.0 0N.H v0.0 0.0m H.NN 0.v H.m 0.H 0.H 0.0 0.0 vbIm In 00.HH 00.0 «mm.a v0.0 «HN.H mm.0 «0.mH 0.0a «0.m m.m «N.H h.0 «0.0 0.0 thN lb «00.0 «00.0 «0.70 «0.0 «0.0 «0.0 «H.N whlmmlm «00.0 00.0 «0H.0 h0.0 «00.0 50.0 «v.0 v.0 «0.H 0.a «H.0 v.0 «N.H 0.0 th0HIm 0H.m «00.H «50.0 «00.0 «00.0 «00.0 «0.0 «v.0 «0.0 «5.0 «N.H «N.H «v.0 «0.H thHHIm Ha.m mm.0 III «00.0 III «vm.0 III «m.h III «v.a III «H.0 III «m.0 vhlm Iv H0.N 00.H 50.0 00.0 No.0 00.0 v.ma 0.0H h.H 0.0 5.0 N.0 0.0 0.0 VNIH Iv 0H.0 00.0 III III III III III III III III III III III III thV In ma.0 0m.0 mH.0 va.o 00.0 00.0 «.0 m.m 0.H 0.H 0.0 0.0 0.0 v.0 vulm Im NN.0 v0.0 ha.0 0v.0 va.o 0m.0 H.0 m.0 0.N H.m v.0 0.0 0.0 0.0 th0NIN 00.0 NH.0 0H.0 HH.0 00.0 00.0 0.0 0.0 0.H N.H 0.0 0.0 5.0 5.0 thNNIN 00.0 00.0 vH.0 mm.0 ma.0 00.0 0.5 0.0 0.H m.a 0.0 m.0 0.0 0.0 ¢hI0NIH om.o oH.o III III III III III III III III III III III III «FIHNIH 0h.a v0.H «00.0 00.0 «00.0 MH.0 «0.0 0.0 «v.H 0.H « Qz N.0 «v.0 0.0 mnIvaHH «00.0 III III III III III III mulmalm ~0.H Hm.0 0m.0 «0N.0 0N.0 «00.0 N.NH «n.ma h.a «0.0 m0.0 «m.H 0.N «v.H mnlm I0 «00.0 «v0.5 III III III III III III III III III III III III mnIm In «No.0 «00.0 III III III III III III III III III III III III mnIofluo H\m 500 Sam 5mm 8mm Ema Ema 3 m 3 m 3 m 3 m 3 m 3 m 3 m v v m ucmanmm m Hmuoe m\ on Ho z\zflx 2\ mz 2\ oz .mvmsmumums umoz 0:0 ummm co “mum: 000:50 00 AH\00 ucoucoo ucoswwmm 0cm A8000 acoucou ucmfluusz mmmuw>dII.¢ 04008 57 The NH4/N of the runoff water phase followed much the same pattern as the NO3/N. The east watershed shows high NH4/N (1.5 ppm) on 8-9-73, and both watersheds were low during winter 1973-1974. High NH4/N on 5-11-74 (1.2, 1.2 ppm) represents an active nitrogen cycle in the spring plus any residue from the fall. The highest NH4/N in the water-phase was found on 5-29-74 (3.8 ppm), 9 days after fertilization. Ammonium nitrogen of runoff water phase decreased thereafter. Kjeldahl nitrogen of the water phase shows a pattern similar to NO3/N and NH4/N. A high content of KjN/N was found on the east watershed on 8-9-73 (3.4 ppm). Winter 1973-1974 has low KjN/N content except for the east water— shed on 2—28-74 (3.1 ppm). This particular runoff was the final melting of an extended snowmelt over partially thawed soil. Fine organic matter may have been differentially removed in this runoff. High PO4/P content of the runoff from the east watershed on this date supports that conclu- sion. Water phase KjN/N was high on 5-11-74 (2.9, 2.4 ppm). This was similar to the NO3/N and NH4/N data and reflected the status of the soil in early spring. The highest KjN/N was found on 5-29-74 (4.9 ppm), 9 days after fertilization. Kjeldahl nitrogen in the water phase of runoff samples decreased thereafter. 58 Chloride content of the water phase of runoff was similar to that of nitrogen. High C1 contents were found on 8-9-73 (12.7, 12.2 ppm), 4-1-74 (10.2, 12.4 ppm), 5-29-74 (9.6 ppm), 7-2-74 (18.0, 13.8 ppm), and 7-9-74 (22.1, 25.8 ppm). High Cl on 8-9—73 shows what was present after a summer with very little runoff. Low Cl contents during the winter reflect snowmelt. The high C1 content in the samples from both watersheds on 4-1-74 reflect rain on thawed soil in the Spring. Soils data discussed later show higher Cl at the soil surface in spring 1974 than in fall 1973. This may account for higher removal of C1 by rain on thawed soil on 4-1-74 than on 1-26-74. Chloride content of the water phase of runoff increased by 5-29-74 (9.6 ppm) after added fertilizer of 5-20-74. It continued to increase to a maximum on 7-9-74 (22.1, 25.8 ppm). Increasing Cl reflects the more even distribution of fertilizer over the watershed after initial application of the fertilizer granules. More even dis- tribution of the fertilizer overtjmawatershed (caused by dissolution and migration in soil solution) leads to greater chance for removal in runoff. Phosphate phosphorus and total P content of the water phase of runoff follow both sediment content of the water and fertilization practices. Phosphate phosphorus and total P in parts per million are higher with higher 59 sediment in grams per liter. Large increases were also noted after fertilization in spring, 1974. Phosphate phos- phorus and total P contents were high on 8—9-73 (0.26, 0.20; 0.26, 0.20 ppm). This reflects what was present after a summer of little runoff. Phosphate phosphorus and total P were high again on the east watershed on 1-26-74 (0.24; 0.25 ppm). This was a runoff with high sediment removal in grams per liter. High PO4/P and total P on the east watershed on 2—28-74 (0.30; 0.40 ppm) may reflect differential removal of lighter weight organic materials in a runoff over partially thawed to frozen soil as dis- cussed under the Kjeldahl nitrogen section. Low PO4/P and total P with high sediment removal on 4-1-74 (0.05, 0.02; 0.08, 0.07 ppm), 4-3—74 (0.24; 0.05 ppm), 5-11-74 (0.02, 0.06; 0.09, 0.07 ppm), and 5-16-74 (0.07, 0.08; 0.07, 0.10 ppm) reflect that most of the movable PO4/P and total P were removed in previous runoffs. The high increases on 5-29-74 (0.10; 0.88 ppm), 7-2-74 (0.93, 1.21; 0.64, 1.32 ppm), and 7-9-74 (0.94, 1.28; 0.86, 0.73 ppm) reflect higher sediment removal in grams per liter but also reflect the application of phOSphorus fertilizer on 5-20-74. Almost all phosphorus found in the water phase of runoff was found as orthophosphate. 60 Nutrient Content of Sediment Phase Table 5 shows the average nutrient content in parts per million of the sediment phase of runoff for both water- sheds. It also repeats Specific sediment contents in grams per liter from Table 4. Nitrate nitrogen contents range from 7 to 34 ppm, NH4/N from 10 to 112 ppm, KjN/N from 2751 to 5487 ppm, and PO4/P from 92 to 378 ppm. Nitrogen contents of the sediment phase of runoff do not show trends as clearly as the water phase. A decrease occurs in NO3/N between summer and fall, 1973, and spring, 1974. This is followed by an increase in NO3/N after fertilization on 5-20-74. Ammonium nitrogen seems quite high on 4-1-74 (92, 112 ppm), but this may represent ammonification in the very early spring. Ammonium nitrogen decreased in May, 1974, but increased after fertilization on 5-20-74. It continued to remain high during the summer. Kjeldahl nitrogen of the sediment phase shows only the trend of being high in April and May, 1974, prior to plow- ing. Phosphate phorphorus in the sediment phase increased as sediment content of runoff increased. It also increased after fertilization in the spring of 1974. High sediment contents on 5-ll-74 (5.18 g/l) and 5-16—74 (5.60 g/l) 61 .mwmmHmcm How magmaflm>m meEmm mco maco« 00.m Nv.m 0mm mam hvmm 000m mm as ea ma thhmIm 0H.m v0.m mam «mm nmom vmom 0v mm 0H ma thmalm «om.ma «o~.m 05m 0mm 00mm omwm «m 03 mm 5H thm In 00.HH m0.0 «Hom mmm «Hmom 0vam «vm «v «vm mm thm In «00.0 «Hma «0mmm «mm «mm thmNIm 00.0 moa vwmm 0H Ha th0HIm 0H.m «mm «Homv «vv «5 wnIHHIm «Nm.0 «OHN «H000 «vv «0H whim Iv Ho.m 0m.H ova ova hmvm mavw NHH mm ma 0H «FIH Iv om.m 00.0 «00 mam H000 Hmhm v0 5v 0N ma v>I0NIH v0.H mHH ommm mm mm manmIHH ~0.H Hm.0 «NHH «moa «50mm «mmvm «Hm «mm «mm «Hm mnIm I0 H\0 Ema Ema Ema Ema 3 m 3 m 3 m 3 m 3 m ucmsflcmm m\vom 2\zflm 2\qmz Z\moz .mcmnmuwumz ummz 0cm ummm so “mums mmocsm mo AH\00 ucmucoo ucmEHUmm 0cm ucwEHQmm wwocsm 00 A8000 pampcou ucmfiupsz momum>4II.m 00009 62 did not produce high phosphate contents, but after the fertilization of 5-20-74 both sediment contents in grams per liter and phosphate content of the sediment were high. Soil Samples Tables 6 through 21 give nutrient content in parts per million of soil cores from east and west watersheds by area and with depth for 1973 and 1974. The tables provide information regarding both downward and lateral movement of nutrients on the watersheds. Sampling Variability Table 22 shows data collected to determine soil sampling variability in the field. Five composite samples, comprised of ten cores each, were collected for four dif- ferent increments from two different areas of the east water- shed. The 1973 area scheme was used. The samples were collected on 9-12-74, a time when both NO3/N and Cl content was low. Consequently, only PO4/P was considered in cal- culating an 5 value. (The 5 value is the standard devia- tion, or root mean squared deviation of the numbers in a sample of size n. It is the square root of the variance.) Pooling data from all four PO4/P area-increments gave an 5 value of 11.32 ppm. Pooling just the surface depths, area 1, 0-1 cm, and area 3, 0-1 cm, gave an 8 value of 14.34 ppm. Pooling the subsurface depths, area 1, 7.5-15 cm, and area 63 TABLEEL--Soil Cores, East Watershed, 6-73 to 5-74 (ppm NO3-N). 6-9-73 6-18-73 7-4-73 8—11-73 9-30-73 11-5-73 5-2-74 Area 1 Depth 1 13 20 21 16 22 7 19 2 15 15 22 13 17 4 5 3 15 16 23 20 14 3 4 4 15 21 3O 4O 18 5 4 5 37 19 9 5 6 24 21 15 5 7 14 19 ll 5 8 8 3 9 10 2 10 18 2 11' 8 2 12 4 2 Area 2 Depth 1 12 17 23 20 22 25 14 2 12 14 12 10 13 4 5 3 8 15 14 17 10 4 4 4 9 17 13 18 15 3 4 5 61 16 6 6 6 20 26 7 6 7 9 12 9 5 8 9 2 9 6 2 10 9 2 11 4 2 12 2 2 Area 3 Depth 1 10 l6 17 35 18 6 15 2 10 15 15 23 16 5 5 3 10 l4 16 23 10 3 3 4 9 18 28 24 27 3 4 5 18 21 5 5 6 10 16 8 5 7 2 16 8 4 8 8 2 9 8 3 10 4 3 11 4 2 12 3 2 Area 4 Depth 1 9 13 25 8 21 4 13 2 12 ll 19 9 l3 4 4 3 8 13 15 9 l7 2 3 4 9 l6 l7 l7 l7 5 4 5 20 15 5 4 6 15 11 5 6 7 5 l4 7 4 8 9 3 9 7 2 10 6 2 ll 5 2 12 2 2 64 TABLE 7.--Soil Cores, West Watershed, 6-73 to 5-74 (ppm NOB-N). 6-9-73 6-18-73 7-4-73 8-11-73 9-30-73 11-5-73 5-2-74 Area 1 Depth 1 14 25 26 19 19 ll 40 2 18 15 19 12 13 6 4 3 19 16 20 21 15 6 6 4 17 20 32 39 ll 4 5 5 33 20 6 5 6 27 15 11 6 7 7 15 12 6 8 12 3 9 9 2 10 5 5 ll ' 5 3 12 3 3 Area 2 Depth 1 13 25 24 l3 l4 9 24 2 l8 14 20 9 13 7 5 3 17 15 17 15 12 4 4 4 17 21 21 31 14 4 5 5 24 23 4 5 6 21 13 9 5 7 8 8 5 8 9 3 9 ll 3 10 6 2 11 3 2 12 2 2 Area 3 Depth 1 9 19 22 8 19 7 l4 2 11 12 10 7 8 3 3 3 13 17 12 9 l6 3 3 4 9 15 17 15 14 4 3 5 14 15 4 4 6 8 l7 8 3 7 10 6 4 8 7 3 9 5 2 10 6 3 ll 3 2 12 2 3 Area 4 Depth 1 10 18 23 9 24 7 21 2 ll 12 ll 7 12 4 4 3 9 ll 9 8 12 3 3 4 8 18 13 15 18 5 4 5 14 20 5 4 6 8 l9 7 5 7 10 8 4 8 4 2 9 7 2 10 4 2 ll 6 3 12 2 3 65 TABLE 8.--Soil Cores, East Watershed, 6-73 to 5-74 (PPm Cl). 6-9-73 6-18—73 7-4-73 8-11-73 9-30-73 11-5-73 5-2-74 Area 1 Depth 1 162 65 33 18 6 2 7 2 122 62 34 29 3 2 5 3 140 107 55 54 9 2 5 4 202 147 69 121 3 2 5 5 70 11 5 6 6 12 24 3 6 7 10 40 4 4 8 9 9 9 24 9 10 46 7 11' 27 6 12 15 5 Area 2 Depth 1 300 64 17 14 5 3 8 2 216 50 4 15 6 1 4 3 163 80 16 16 5 4 3 4 61 117 35 56 9 1 2 5 74 14 1 4 6 23 26 2 6 7 5 25 2 5 8 10 5 9 21 9 10 37 8 11 20 5 12 10 13 Area 3 Depth 1 233 80 24 97 5 9 8 2 171 87 30 55 5 2 5 3 77 95 34 95 16 6 10 4 36 105 64 77 21 6 7 5 43 17 1 6 6 6 17 2 7 7 8 21 3 9 8 21 11 9 24 6 10 18 6 11 12 6 12 12 6 Area 4 Depth 1 179 136 22 24 4 7 8 2 215 92 19 14 5 1 5 3 186 120 33 17 5 2 8 4 177 196 52 24 7 2 6 5 48 10 1 4 6 32 17 7 5 7 8 20 4 4 8 17 6 9 19 8 10 37 8 11 43 9 12 12 13 66 TABLE 9.--Soil Cores, West Watershed, 6-73 to 5-74 (ppm C1). 6-9-73 6-18-73 7-4-73 8-11-73 9-30-73 11-5-73 5-2-74 Area 1 Depth 1 246 63 71 24 6 8 5 2 285 58 54 18 9 8 3 3 302 106 65 48 7 2 5 4 44 141 116 100 13 7 7 5 89 17 12 6 6 23 31 9 4 7 3 36 16 5 8 27 6 9 33 6 10 14 ll 11‘ 20 10 12 18 14 Area 2 Depth 1 271 95 28 18 5 9 10 2 273 64 24 10 7 1 4 3 248 147 37 33 8 7 5 4 101 155 51 82 ll 14 4 5 69 17 5 3 6 19 22 6 5 7 43 10 5 8 7 6 9 22 6 10 42 6 ll 11 5 12 4 5 Area 3 Depth 1 141 89 8 7 8 9 6 2 238 61 8 9 6 7 6 3 316 93 8 18 8 5 9 4 181 122 22 3O 8 7 7 5 43 10 4 7 6 25 18 2 6 7 15 7 7 8 ll 6 9 l3 8 10 4O 13 ll 21 13 12 7 18 Area 4 Depth 1 229 84 16 23 10 10 9 2 127 78 5 12 ll 5 6 3 136 86 15 32 8 6 6 4 122 139 23 54 13 2 5 5 55 11 8 8 6 24 22 10 7 7 4O 4 8 8 7 5 9 20 8 10 19 7 11 21 10 12 8 l2 67 TABLE lO.--Soil Cores, East Watershed, 6-73 to 5-74 (ppm PO4-P). 6-9-73 6-18-73 7-4-73 8-11-73 9—30-73 11-5-73 5-2-74 Area 1 U ('D "O 9 p \OGJQO‘U'IIwa 96 93 95 101 94 100 95 87 66 75 80 77 82 80 82 83 96 95 90 92 94 91 93 95 72 79 80 82 92 92 94 92 89 93 94 89 94 103 94 104 90 80 84 92 87 92 93 84 96 102 112 112 118 106 107 92 98 93 9O 9O 9O 69 65 72 88 82 92 98 36 90 100 97 96 97 98 55 94 106 102 106 108 99 81 90 98 91 94 94 89 70 76 84 9O 80 9O 68 43 9O 94 91 80 88 72 39 76 92 91 89 88 93 7O 32 7 O‘IbCO 76 92 88 97 104 106 104 86 96 97 94 99 96 46 24 12 6 7 8 92 96 98 96 102 105 100 26 10 7O 94 105 104 101 102 62 10 11 78 96 94 98 107 102 68 TABLE 11.--Soi1 Cores, West Watershed, 6-73 to 5-74 (ppm PO4-P). 6—9-73 6-18—73 7-4—73 8-11-73 9-30-73 11-5-73 5-2—74 Area 1 Depth 1 46 51 56 50 54 43 45 2 42 52 52 51 58 46 50 3 48 52 52 48 6O 54 51 4 51 54 54 52 53 46 58 5 6O 54 49 54 6 65 31 57 6O 7 42 22 35 40 8 4 5 9 3 4 10 10 4 11 ll 3 12 4 6 Area 2 Depth 1 62 57 56 62 56 56 46 2 57 58 56 76 64 63 57 3 60 56 57 76 62 54 56 4 6O 54 52 74 67 61 56 5 8O 62 54 67 6 85 13 55 63 7 14 44 26 8 5 4 9 5 4 10 4 3 11 4 6 12 6 6 Area 3 Depth 1 46 65 64 66 69 58 50 2 52 50 68 60 71 59 63 3 46 6O 62 59 74 58 66 4 45 6O 62 64 76 76 56 5 67 73 56 54 6 62 65 68 69 7 32 46 25 8 13 5 9 10 6 10 8 10 11 8 9 12 9 7 Area 4 Depth 1 56 56 56 54 53 52 48 2 64 54 56 50 6O 59 59 3 56 53 67 58 56 42 67 4 54 50 78 51 54 56 62 5 66 52 54 61 6 68 25 52 72 7 22 21 52 8 ll 10 9 8 7 10 8 5 11 9 4 12 8 5 69 TABLE 12.--Soi1 Cores, E. Watershed, 5-74 to 9-74 (ppm NOB-N) . 5-22-74 5-30-74 7-3-74 8-5-74 8-14-74 9-3-74 Area 1 Depth 1 88 21 114 10 6 1 2 34 12 82 13 5 2 3 25 25 103 50 14 4 4 15 36 63 77 32 ll 5 4 15 20 60 18 6 3 6 10 14 33 7 2 6 7 3 4 Area .2 Depth 1 29 22 55 4 4 1 2 38 12 56 5 1 l 3 39 16 14 5 2 3 4 31 28 64 11 5 3 5 0.5 10 24 22 13 6 4 6 15 21 25 7 5 10 11 14 6 Area 3 Depth 1 50 8 40 4 1 1 2 65 8 32 4 l l 3 65 14 47 11 1 2 4 25 18 66 8 2 2 5 5 16 26 4 4 6 8 5 13 10 4 7 7 3 10 1 21 Area 4 Depth 1 52 14 98 10 5 l 2 90 10 92 8 5 2 3 51 16 93 17 18 4 4 4 26 51 45 39 6 5 6 15 14 40 ll 6 4 6 10 8 24 7 5 6 7 1 2 Area 5 Depth 1 61 18 235 5 2 1 2 51 12 135 7 2 l 3 35 19 113 14 4 2 4 8 46 68 24 ll 3 5 4 29 20 22 13 6 5 7 15 12 13 7 6 7 10 3 10 Area 6 Depth 1 33 16 182 5 1 1 2 48 7 112 4 2 1 3 35 14 142 13 2 1 4 9 32 82 32 2 1 5 5 36 18 8 2 6 4 7 11 9 l7 7 5 6 8 2 10 70 TABLE l3.--SOil Cores, w. Watershed, 5-74 to 9-74 (ppm NO3-N). 5-22-74 5-30-74 7-3-74 8-5-74 8-14-74 9-3-74 Area 1 Depth 1 48 14 38 8 2 1 2 60 8 38 9 5 1 3 40 14 70 12 8 1 4 23 35 72 30 9 1 5 4 30 23 29 5 6 3 7 14 38 18 7 4 6 9 5 10 Area .2 Depth 1 40 8 40 8 4 1 2 40 8 49 8 4 1 3 48 22 77 6 7 l 4 37 30 68 13 17 1 5 3 22 29 29 4 6 2 6 16 25 4 7 6 6 9 13 19 Area 3 Depth 1 80 12 55 14 4 1 2 66 9 57 12 5 1 3 33 20 78 26 ll 1 4 20 26 58 67 16 3 5 5 24 24 26 11 6 4 6 l3 17 22 7 6 3 8 6 19 Area 4 Depth 1 56 15 41 10 5 1 2 95 10 59 8 5 1 3 62 17 99 22 5 2 4 7 19 76 52 10 4 5 6 12 25 35 19 6 4 7 l4 14 31 7 6 7 9 5 10 Area 5 Depth 1 63 8 70 6 4 l 2 60 9 75 8 4 2 3 36 14 94 24 6 l 4 8 24 69 70 16 3 5 4 29 23 20 13 6 5 10 14 27 30 7 7 7 9 19 26 Area 6 Depth 1 30 12 16 4 4 l 2 44 10 52 10 4 1 3 35 20 69 24 10 l 4 10 34 54 55 21 2 5 4 18 24 60 6 6 4 6 13 33 ll 7 5 6 11 7 12 71 TABLE 14.--Soi1 Cores, E. Watershed, 5-74 to 9-74 (PpmNH4-N). 5-22-74 5-30-74 7-3-74 8-5-74 8-14-74 9-3-74 Area 1 Depth 1 42 26 14 ll 5 9 2 31 22 1 11 2 4 3 25 25 6 9 l 0.5 4 18 15 0.5 4 1 0.5 5 2 0.5 1 0.5 1 6 2 0.5 5 0.5 0.5 7 3 0.5 14 0.5 0.5 Area .2 Depth 1 30 23 2 5 4 9 2 41 31 9 2 2 6 3 52 20 7 l 0.5 2 4 33 0.5 2 1 0.5 0.5 5 2 0.5 l 0.5 0.5 6 l l 1 0.5 1 7 2 1 l 0.5 1 Area 3 Depth 1 46 23 112 3 3 8 2 61 10 3 2 0.5 6 3 80 14 2 1 0.5 l 4 30 0.5 2 1 0.5 1 5 4 l 2 0.5 1 6 7 1 1 0.5 l 7 3 1 2 0.5 2 Area 4 Depth 1 ' 40 14 34 12 6 12 2 83 6 19 10 4 6 3 57 2 4 6 2 0.5 4 5 4 1 5 1 0.5 5 3 0.5 l l 4 6 2 2 2 1 2 7 2 0.5 2 0.5 0.5 Area 5 Depth 1 48 21 7 13 4 12 2 60 18 38 10 1 11 3 37 15 14 2 1 0.5 4 4 18 5 1 0.5 1 5 2 3 2 0.5 0.5 6 1 l 2 1 1 7 1 l 1 1 0.5 Area 6 Depth 1 28 20 20 10 5 8 2 47 11 4 6 2 3 3 40 38 3 4 l 0.5 4 9 15 l 3 0.5 0.5 5 1 2 1 l 1 6 2 0.5 1 0.5 1 7 3 0.5 1 0.5 0.5 72 7-3-74 8-5-74 8-14-74 9-3-74 5-30-74 TABLE 15.--5011 Cores, w. Watershed, 5—74 to 9-74 (ppm NH4-N). 5-22—74 9611 555 O O 0 4728000 1 << 555 O .0 7860000 3442< .l. h t p e D 55555 0 1100000 <<< 5 55 51.10100 Area 55555 2200000 <.<< 5 55 0 O 0 7610100 13 11 36 33 57 31 E o. o. z: ‘\ :z a: West Waters '53:!” $8 r ppm 85 1100 1000 900 800 700 600 500 400 KjN/N East Watershed KjN/N ppm vs. Date COOIOOOOIOOOOOOOOC 1000 900 800 700 600 500 400 Figure 8.-Kjeldahl nitrogen content of the 0-1 cm. depths of east and west watersheds by date. K.N/N 0 E. W > E Q 0. z \ z --. 2 'U 0 .C m L. 0 u ‘0 3 H m 0 3 IIOO 86 IOOO 900 800 700 600 500 K.N/N East Watershed KjN/N ppm vs. Date 1000 900 800 700 600 500 400 Figure 9.-Kje1dah1 nitrogen content of the l-2.5 cm. depths of east and west watersheds by date. 87 the 0-7.5 cm depths on 5-22-74 after the fertilization of 5-20-74. By 5-30-74 there was a large decrease in the Cl content in the 0-5 cm depths, and the highest content was found 5-7.5 cm deep. By 7-3-74 Cl increased back to or higher than the levels of 5-22-74 in the 0-5 cm depths. This is explained by a salinity effect or the upward move- ment of salts in soil solution as water is evaporated from the soil surface. After 7-3-74 chlorides leached downward, and on 9-3-74 the peak was seen in the 7.5-30 cm depths. Figure 10 shows the PO4/P content in parts per million in the 0-2.5 cm depths of all areas of the east watershed. Graphing of the remaining five increments of the profile would show similar results. Figure 10 shows that on areas 1 through 4 PO4/P either stayed about the same over the summer or decreased. On areas 5 and 6 PO4/P increased over the summer. Clearly PO4/P materials were deposited on area 5 by the runoff of 7-2-74. Area 6 also showedaniincrease in PO4/P which must result from deposi- tion on 7-9-74, 8-13-74, or 8-27-74. The data from the west watershed does not show the increase in PO4/P on areas 5 and 6. However, the west watershed is shaped differently from the east one. Water tends to run quickly over and off areas 5 and 6 of the west watershed. On the east watershed it ponds for a much longer 88 .oump an pmsmumumz ammo on» no mnummp Eo m.~:o on» no ucmucoo msuosmmonm Eum.Nu_ Eon : umo .m> m\ on mtmumz ummm : mmt< m mwt< .8 To Eng a mo .m> a\ on mt6um3 umMu : mmt< m mmt< mumnmmonmnn.oH musmwm oo— ON— 0:— cm. om— CON CNN End as oo— ON— 0:— cm— on. ooN CNN on Eng a: on 89 time with corresponding increased chances for deposition of organic matter and eroded soil. The PO4/P content of runoff waters and sediment from the runoffs of 7-2-74, 7-9-74, 8-13-74, and 8-27-74 further support evidence of phosphate movement from the upper slopes onto the lower $10pes or off the watershed. The dramatic increase in PO4/P on area 5 of the east watershed on 7-3-74 shows that the runoff water picked up the available phos- phorus from the fertilization of 5-20-74. Increases in PO4/P on area 5 after 7-3-74 were not as great because the most readily movable PO4/P was moved by the runoff of 7-2-74. Mass Balance Table 23 shows the total sediment (kg/ha) lost from 6-73 to 8-74 by event date. The data was calculated TABLE 23.--Total Sediment Lost from the Watersheds in Run- off (6-73 to 8-74). Date East Watershed West watershed kg/ha kg/ha 11-24-73 4,1 1-26—74 132.0 12.0 4- 3-74 16.3 5-16-74 7,0 7— 2-74 129.0 100.0 7- 9-74 4.0 48.0 8-13-74 274.0 399.0 8-27-74 231.0 173.0 TOTAL 797.4 732.0 90 from average sediment content (g/l) in each runoff event and runoff magnitude. Table 24 shows total NO -N, NH -N, 3 4 KjN, and PO4/P (kg/ha) lost from the watersheds in water and sediment phases of runoff from 6-73 to 8-74. Magnitude of sediment lost per event depended on sediment content (g/l) of the runoff and runoff magnitude. Table 23 shows high losses from both watersheds on 7-2-74, 8—13-74, and 8-27-74. The totals lost for the period 6-73 to 8-74 are quite similar for the two watersheds: 797.4 kg/ha on the east watershed, and 732.0 kg/ha on the west watershed. The data in Table 24 show that NO3-N and NH4-N were mainly lost in the water phase of surface runoff. On the east watershed 95% of the NO3-N and 77% of the NH4-N were in the water phase. On the west watershed 94% of the NO3-N and 78% of the NH4-N were in the water phase. KjN was lost mainly in the sediment phase of sur- face runoff. On the east watershed 79% of the KjN was in the sediment phase, and on the west watershed 86% was in the sediment phase. Total N from the watersheds was lost mainly as KjN. On the east watershed 91% of total N was lost as KjN, and on the west watershed 92% was lost as KjN. About twice as much PO -P was lost in the sediment 4 phase as in the water phase of surface runoff. On the east 91. q 053 2.08653 .7 ca 138. sex? m3 33H 8. 2.0: 60008 0 H38. mn\0x e0.~ 00>osmu z H0009 ss\0x mm lemma ou memav 00000 2 H0009 mm.ea~ Hm.ee 00.0NH «H.0H 0a.0m usmsaomm 00.00 00.nm em.me 00.0 00.aa 0e.0 0a.m He.0 sows: a- 00 m0.0emm 00.0em 00.0mma me.0ma 0H.mom ucwaaomm ~0.Nem mm.00 0m.0ma 00.0H me.mm ~0.0 0H.H0 me.0 “mums zflz 00.00 00.0 ma.ma m0.a 00.0 namsatom 00.e0 vm.0a e~.Hm N0.m H0.0H em.m H0.mm 0H.N noun: 0 z- zz m0.ma me.H 0m.0 vm.a 00.0 00050000 em.00~ H0.0m 0H.0e em.mm 00.me 0m.0 me.0m 0H.~ Hams: z- oz ms\0x emr0om>oepnauvoa Hence mrxox m0H reams on name. 00660 a sauce msxax am.m 00>o20u z sauce msxmx mam Assad 0» memao 0000s z annoy 0H.0N~ 0N.Ns 0e.ee mm.a 00.me as.0 «0.0 00.00 00.0 usmsaeom ea.maa 00.mm 00.H0 0H.H m0.ma 00.0 00.0 00.0 m0.aa 0m.m 00.0 mm.0 news; a. om em.mmm~ 00.H00 em.mm0 00.ma m~.eoe He.m~ 0m.mo ma.mom 00.0H ucmaaeom me.mm0 00.00H 00.00H 00.m 00.00 mm.~ 0m.m om.ma «H.0NH 00.HHH 00.00 00.0 “was: zflz 00.~m 00.0H 00.00 Hm.0 0e.m e0.0 00.0 0N.0 00.0 usoaavom ma.00a 0m.0e 00.m0 00.m 00.0a 00.0 mm.0 00.m 00.4m 00.nm 00.0 0m.0 news: . z- mz 00.0a 00.0 00.0 00.0 00.~ 00.0 Hm.0 00.H 0H.0 usoaaowm ma.00~ me.mm 00.a0 00.HH 00.00 00.H me.0 mm.m 00.0a me.00 00.~a mm.a ummmz z: oz mfim sauce enuemlm veama-m eh-0-e «humus 00-0anm eeum-q ee-mum enummum «summum we-0~-a mensmuaa 0 0.xveummou menov unease mo demand unmaaemm 0cm smut: ca memrmuoumz are 5000 when a- on new .zflx .z- :z .2. oz amuoeuu.0m mamas 92 watershed 67% of the PO4-P was lost in the sediment phase. On the west watershed 70% of the PO4-P was lost in the sediment phase. Total N added to the east watershed from 6-73 to 8-74 was 225 kg/ha. Total P added was 105 kg/ha. On the west watershed 95 kg/ha N and 105 kg/ha P were added from 6-73 to 8-74. Total losses of N and PO4-P were quite similar for the two watersheds. The east watershed lost 3.31 kg/ha N and 0.34 kg/ha PO -P. The west watershed lost 2.87 kg/ha 4 and 0.31 kg/ha PO -P. 4 Nitrogen losses in runoff were equivalent to 1.5% of input fertilizer N ontflmaeast watershed and 3.0% of input on the west. Losses of P were equivalent to 0.3% of applied fertilizer P on both watersheds. Soil Phosphorus: Comparison Between Virgin and Cultivated Watershed Soils Table 25 shows total P (ppm), PO4/P (ppm), and organic matter (5) for a profile from area 1 of the east watershed, and a profile of virgin soil from a forest near the watersheds. The data show high total phosphorus from 0.22.5 cm, high PO4/P from 0-30 cm, and high percent organic matter from 0-30 cm on the cultivated watershed soil. On the virgin soil total P is high from 0-46 cm, PO4/P high from 0-61 cm, and percent organic matter stayed 93 TABLE 25.--Comparison of Total Phosphorus (ppm) , Phosphate Phosphorus (PPm) and Percent Organic Matter between Cultivated Watershed Soil and Virgin Soil. East Watershed Virgin Soil Depth 11-5-73 Area 1 12—29-73 cm Total P PO4/P O.M. Total P PO4/P O.M. PPm PPm % ppm ppm % 0 -.1 719 76 1.76 512 29 10.07 1 - 2.5 812 92 2.21 275 34 7.50 2.5- 5 762 91 2.21 212 34 6.00 5 - 7.5 844 89 1.98 419 38 5.43 7.5-15 781 88 2.12 369 32 2.86 15 -22.5 856 93 2.12 312 32 1.71 22.5-30 562 70 2.14 306 25 1.28 30 -38 500 32 1.14 294 26 1.28 38 -46 219 7 0.71 331 25 1.60 46 -61 312 8 0.90 250 34 1.10 61 -76 344 4 0.60 206 18 1.12 76 -91 406 6 0.43 250 15 1.14 94 in the same range from 22.5-91 cm. Total phosphorus and PO4/P were higher on the cultivated soil than the virgin soil 0-30 cm deep. Percent organic matter is much higher in the 0-7.5 cm depths of the virgin soil than that culti- vated. Study of fertilizer records show that 990 kg/ha phosphorus have been added to the east watershed since 1956. Consequently we find the total P and PO4/P at higher levels on the cultivated soil. The PO4/P data from the cultivated watershed show that orthophOSphates have moved deeper in the profile than the zone of maximum total phOSphorus. Depth 22.5-38 cm on the cultivated watershed has not yet reached maximum P adsorption. Total phosphorus and PO4/P contents on the cultivated watershed were closely related to percent organic matter. On the virgin soil total P and PO4/P maintain the same levels deeper in the profile than on the cultivated soil. Except for high total P 0-1 cm deep, total P and percent organic matter appear unrelated. Phosphate phos- phorus also appears independent of percent organic matter on the virgin soil. Comparisons of the virgin and cultivated soils show that cultivation and crOpping decreased organic matter and fertilization increased total P and PO4/P. Cropping also depleted the lower depths of total P and PO4/P whereas the virgin soil had a more equal distribution of total P and PO4/P with depth. CONCLUSIONS Summer runoff magnitudes on the experimental water- sheds depended on rainfall intensity, duration of rainfall after the start of runoff, and soil structure on the event date. Runoff magnitude increased with increasing rainfall intensity, increasing duration of rainfall after the start of runoff, and increasing bulk density or compactness of the soil surface. Winter runoffs depended on the amount of rain and accumulated snow on the watersheds and the rise in temperatures above 23 F. Sediment content of runoff samples in grams per liter depended on the structure of watersheds on the runoff event date. During the summer seasons the highest contents were found in early summer after tillage operations. Dur— ing the winter season contents were quite low when the soil was frozen and higher when the soil was thawed or partially thawed. The NO3/N, NH4/N, and KjN/N contents of runoff waters and sediment during the winter season were generally quite low. Winter runoffs with higher NO3/N occurred when the water moved over thawed or partially thawed soil. Lighter weight organic matter may have been differentially removed in such runoffs. 95 96 The NO3/N, NH4/N, and KjN/N contents of runoff waters and sediment increased in the spring above the values of the winter runoffs. These increases reflected the warm- ing of the soil and the nitrogen cycle in the spring. Con- tents of NO3/N, NH4/N, and KjN/N in runoff waters were highest in the runoffs following spring fertilization. Sediment contents of NO3/N and NH4/N but not KjN/N were also high following spring fertilization. Sediment and water phase runoff concentrations of NO3/N, NH4/N, and KjN/N decreased in successive runoffs after the initial high values in the first runoffs after fertilization. Chloride contents of the runoff sediment and water were low during the winter season. Increases in the spring reflected the thawed soil and an upward movement of chloride to the surface soil as seen in soil sample data. Chloride contents of runoff sediment and water phases were highest in early summer and decreased thereafter. The PO4/P and total P contents of runoff waters, and the PO4/P content of runoff sediments reflected both sediment content of the runoff samples in grams per liter and the spring fertilization. The PO4/P and total P con- tents increased as sediment content increased except for the spring runoffs prior to fertilization. The runoffs of spring 1974 prior to fertilization had higher sediment con- tents than many of the winter runoffs but were low in PO4/P 97 and total P because prior runoffs during fall and winter had removed most of the easily movable PO4/P and total P. High PO4/P and total P were found in runoffs following fertilization, with successive decreases thereafter. Most of the phosphorus moved in runoff was in the orthophosphate form. Soil cores taken in the summers of 1973 and 1974 show both downward and lateral movement of nutrients. Chlorides and NOB/N leached through the soil during the summer after the high initial application of fertilizer in the spring. Movement of Cl, NO3/N, and PO4/P from upper watershed areas to the lower flume approach areas clearly occurred. Nitrate nitrogen in 1974 moved to the flume approach areas in runoff. In 1973 there was some indication of NO3/N movement in runoff although the evidence was not as clear. High KjN/N in the flume approach areas throughout summer 1974 was evidence of past movements of nitrogen in surface runoff down the watersheds. Phosphate phosphorus data in 1974 showed movement of PO4/P onto the flume approach areas on the east watershed. The west watershed did not show the same movement, but it was shaped differently than the east watershed and did not get as much ponding of runoff water. 98 Mass balance calculations showed that nitrogen losses in runoff were equivalent to 1.5% of input fertilizer N on the east watershed and 3.0% of input on the west. Total P lost from the watersheds as PO4/P in surface run- off was equal to 0.3% of that added to both watersheds over the same time period. Nitrogen lost in surface run- off was mainly in organic forms. Nitrate nitrogen and NH4/N were mainly in the water phase of runoff. Organic N was mainly in the sediment phase of runoff. Of the PO4/P lost, two thirds was in the sediment phase. Comparisons between a cultivated soil and a virgin soil showed higher organic matter in the virgin soil. Higher PO4/P and total P were found in the cropped soil, but PO4/P and total P had more equal distribution to a greater depth in the virgin soil. REFERENCES 99 REFERENCES Allen, A. L., F. J. Stevenson, and L. T. Kurtz. 1973. Chemical distribution of residual fertilizer nitrogen in soil as revealed by nitrogen--15 studies. J. Environ. Qual. 2:120-124. Benoit, G. R. 1973. Effect of agricultural management of wet sloping soil on nitrate and phosphorus in sur- face and subsurface water. Water Resour. Res. 9: 1296-1303. Biggar, J. W., and D. R. Nielsen. 1962. Miscible dis- placement: II.Behavior of tracers. Soil Sci. Soc. Am. Proc. 26:125-128. Bouldin, D. R., and C. A. Black. 1954. Phosphorus diffu- sion in soils. Soil Sci. Soc. Am. Proc. 18:255- 259. Bremner, J. M. 1965. Inorganic forms of nitrogen. Chapter 85 in C. A. Black, ed. Methods of soil analysis, part 2. Agronomy series 9. Amer. Soc. Agron. Madison, Wisconsin. Cassell, D. K. 1971. Water and solute movement in Svea loam for two water management regimes. Soil Sci. Soc. Am. Proc. 35:859. Corey, J. C., and J. W. Fenimore. 1968. Tracing ground- water with chloride ions and tritium through acid kaolinitic soil. Int. J. Appl. Radiat. Isotop. 19: 741-746. Dahnke, W. C. 1971. Use of the nitrate specific ion electrode in soil testing. Comm. in 5011 Sc1. and Plant Ana. 2:73-84. Edwards, D. M., P. E. Fischbach, and L. L. Young. 1972. Movement of nitrates under irrigated agriculture. Am. Soc. Agric. Engin. Trans. 15:73-75. Frere, M. H. 1973. Adsorption and transport of agricultural chemicals in watersheds. Am. Soc. Agric. Engin. Trans. 16:569-572. 100 101 Fulcher, C. E., and E. H. Tyner. 1959. Movement of chlor- ide ions through unsaturated and saturated cores. Annual report, project 00-15-15-317. Agronomy Department, University of Illinois, Urbana, Ill. Hamon, R. W. 1966. Evapotranspiration and water yield predictions. Conference Proceedings; Evapotrans- piration and its role in water resources mangement. American Society of Agricultural Engineers. St. Joseph, Mich. 49085 pp. 8-9, 13. Hashimoto, I., and J. R. Lehr. 1973. Mobility of polyphos- phates in soil. Soil Sci. Soc. Am. Proc. 37:36-41. Humphreys, F. R., and W. L. Pritchett. 1971. Phosphorus adsorption and movement in some sandy forest soils. Soil Sci. Soc. Am. Proc. 35:495-500. Kirda, C., D. R. Nielsen, and J. W. Biggar. 1973. Simul- taneous transport of chloride and water during infiltration. Soil Sci. Soc. Am. Proc. 37:339-45. Klausner, S. D., P. J. Zwerman, and D. F. Ellis. 1974. Surface runoff losses of soluble nitrogen and phos- phorus under two systems of soil management. J. Environ. Qual. 3:42-6. Kurtz, L. T. 1970. The fate of applied nutrients in soils. J. Agr. Food Chem. 18:773-80. Kurtz, L. T., and S. W. Melsted. 1973. Movement of chemi- cals in soils by water. Soil Sci. 115:231-9. Lawton, K., and J. A. Vomocil. 1954. The dissolution and migration of phosphorus from granular superphos- phate in some Michigan soils. Soil Sci. Soc. Am. Proc. 18:26-32. Linville, K. W.,and G. E. Smith. 1971. Nitrate content of soil cores from corn plots after repreated nitrogen fertilization. Soil Sci. 112:249-55. Logan, T. J., and E. O. McLean. 1973a. Nature of phos- phorus retention and adsorption with depth in soil columns. Soil Sci. Soc. Am. Proc. 37:351-5. Logan, T. J., and E. O. McLean. 1973b. Effects of phos- phorus application rate, soil properties, and leach- ing mode on 32P movement in soil columns. Soil Sci. Soc. Am. Proc. 37:371-4. 102 Munn, D. A., E. O. McLean, A. Ramirez, and T. J. Logan. 1973. Effect of soil, cover,slope, and rainfall factors on soil and phosphorus movement under simulated rain- fall conditions. Soil Sci. Soc. Am. Proc. 37:428-31. Olsen, R. J., R. F. Hensler, O. J. Attoe, S. A. Witzel, and L. A. Peterson. 1970. Fertilizer nitrogen and crop rotation in relation to movement of nitrate nitrogen through soil profiles. Soil Sci. Soc. Am. Proc. 34:448-452. Parker, J. H. 1972. How fertilizer moves and reacts in the soil. Crops and Soils 25:7-11. Phillips, R. E., G. A. Place, and D. A. Brown. 1968. Self- diffusion of phosphorus in clays and soils: I. The effect of phosphorus rate. Soil Sci. Soc. Am. Proc. 32:41-44. Porter, L. K., W. D. Kemper, R. D. Jackson, and B. A. Stew- art. 1960. Chloride diffusion in soils as influ- enced by moisture content. Soil Sci. Soc. Am. Proc. 24:460-463. Pratt, P. F., W. W. Jones, and V. E. Hunsaker. 1972. Nitrate in deep soil profiles in relation to fertili- zer rates and leaching volume. J. Environ. Qual. 1: 97-102. Richardson, C. W., and J. T. Ritchie. 1973. Soil water balance for small watersheds. American Society of Agricultural Engineers Trans. 16:72-7. Romkens, M. J. M., and D. W. Nelson. 1974. Phosphorus rela- tionships in runoff from fertilized soils. J. Environ. Qual. 3:10-13. Romkens, M. J. M., D. W. Nelson, and J. V. Mannering. 1973. Nitrogen and phosphorus composition of surface run- off as affected by tillage method. J. Environ. Qual. 2:292-5. Schuman, G. E., R. E. Burwell, R. F. Piest, and R. G. Spomer. 1973. Nitrogen losses in surface runoff from agri- cultural watersheds on Missouri valley loess. J. Environ. Qual. 2:299-302. Schuman, G. E., R. G. Spomer, and R. F. Piest. 1973. Phos- phorus losses from four agricultural watersheds on Missouri valley loess. Soil Sci. Soc. Am. Proc. 37: 424-7. 103 Shaw, K. 1962. Loss of mineral nitrogen from soil. J. Agr. Sci. 58:145-51. Sievers, D. M., G. L. Lentz, and R. P. Beasley. 1970. Move- ment of agricultural fertilizers and organic insecti- cides in surface runoff. Trans. Amer. Soc. Agr. Engin. 13:323-325. Smith, S. J. 1972. Relative rate of chloride movement in leaching of surface soils. Soil Sci. 114:259-263. Sommerfeldt, T. G., and A. D. Smith. 1973. Movement of nitrate nitrogen in some grassland soils of southern Alberta. J. Environ. Qual. 2:112-115. tewart, B. A. 1970. A look at agricultural practices in relation to nitrate accumulation. (Pp. 47-60 in O. P. Engelstad (ed.), Nutrient mobility in soils: Accumulation and losses, Soil Sci. Soc. Am. Special Publ. No. 4, Soil Sci. Soc. Am., Madison, Wis.). Tisdale, S. L., and W. L. Nelson. 1968. Soil fertility and fertilizers. The Macmillan Company, New York. U. S. Environmental Protection Agency. Methods Development and Quality Assurance Research Laboratory. 1974. p. 207. Methods for chemical analyses of water and wastes. Vaidyanathan, L. V., and P. H. Nye. 1971. The measurement and mechanism of ion diffusion in soils. VII. Counter diffusion of phosphate against chloride in a moisture-saturated soil. J. Soil Sci. 22:94-100. Wallace, A., and R. L. Smith. 1954. Nitrogen interchange during decomposition of orange. and avocado tree residues in soil. Soil Sci. 78:231-242. Wetselaar, R. 1961. Nitrate distribution in tropical soils. II. Extent of capillary accumulation of nitrate during a long dry period. Plant Soil 15:121-133. Williams, C. H. 1971. Reactions of surface-applied super- phosphate with soil. II. Movement of the phos- phorus and sulphur into the soil. Aust. J. Soil Res. 9:95-106. APPENDIX 104 APPENDIX Draft Established Series Subject to Review Hillsdale Series Hillsdale series comprises well-drained soils developed in calcareous sandy loam till with the thickness of the sola ranging from 40 to 60 inches or more. Hillsdale soils are the well-drained member of the drainage sequence which includes the moderately well-drained Elmdale soils, the somewhat poorly drained Teasdale soils and the poorly drained Barry soils. Lapeer soils are also developed in sandy loam till but have a less acid sola which ranges in thickness from 18 to 40 inches. Miami soils which have finer-textured and thinner B2t horizons than Hillsdale soils and are underlain by neutral to calcareous sand and gravel at depths greater than 42 inches. Hillsdale soils are finer-textured throughout the profile than the Coloma and Spinks soils which were develOped on loamy sand parent materials. Kalamazoo soils have neutral to calcareous, stratified sand and gravel at 42 to 66 inches while Hillsdale soils have calcareous sandy 1aom till at 42 to 66 inches or more. The moderately well-drained Hodunk soils also developed on sandy loam till but have a weak to moderate fragipans which are absent in the Hillsdale Soils. Soil Profile: Hillsdale sandy loam Ap 0-9" Sandy Loam: dark grayish brown (lOYR 4/2), very dark gray (lOYR 3/1) or very dark grayish brown (lOYR 3/2), weak, fine, granular structure; very friable or friable low to medium in organic matter content slightly to medium acid abrupt smooth boundary. 6 to 11 inches thick. A2 15-24" Loamy Sand or Sandy_Loam: yellowish brown (lOYR 5/4-5/6 very weak, thick, platy to weak, fine, granular struc- ture; very friable or friable; medium to strongly acid; gradual wavy boundary. 6 to 14 inches thick. Bl 15-24" Sandy Loam: dark brown (lOYR 4/3 - 7.5 4/4) or brown (lOYR 5/3); weak, medium, subangular blocky structure; friable, medium to strongly acid; clear wavy boundary. 6 to 18 inches thick. Bth 24-35" Sandy Clay Loam or Loam: dark yellowish brown (lOYR 4/4) or dark brown (7.5YR 4/4); weak to moderate, medium, subangular block structure; friable; medium to strongly acid; gradual wavy boundary. 5 to 20 inches thick. 105 106 B22t 35-46" Sandy Loam with sandy lenses or layers or variable thick- ness; the finer textures are brown or dark brown (7.5YR 4/4-5/4) while the coarser-textured lenses or layers are brown (lOYR-5/3); weak, coarse, subangular blocky struc- ture; very friable; slightly to medium acid; gradual wavy boundary. 5 to 15 inches thick. B3 46-58" Sandy loam with discontinuous layers, lenses, or pockets, of loamy sand and sand from 2 to over 12 inches in thickness; sandy loam is brown or dark yellowish brown (7.5YR 4/4-10YR 4/4) and the sands are yellowish brown or pale brown (lOYR 5/3 - 6/3); sandy loam is friable and loamy sand is very friable; medium to slightly acid;. abrupt irregular boundary. 5 to 40 inches thick. C 58" Sandy Loam: brown or yellowish brown (lOYR 5/3 - 5/4); massive to very weak, coarse, subangular blocky struc- ture friable; neutral to calcareous. Range in Characteristics: Sandy loam , fine sandy loam, loam and loamy sand types have been mapped. The depth to calcareous materials ranges from 40 to 80 or more inches. The texture of the B2t horizons varies from sandy loam to sandy clay loam within a short distance. In places, the BB horizon is mainly sand with loamy sand and sandy loam lenses and layers similar to the lower sola of Spinks and Coloma soils. The C1 horizon is a loamy sand in some places and ranges in reaction from slightly acid to calcareous. Colors refer to moist conditions. Topography: Nearly level to strongly sloping areas on till plains, mor- aines and drumlins. Drainage and Permeability: Well-drained. Runoff is moderate on the smoother slopes and rapid on the steeper slopes. Permeability is moder- ate. Natural Vegetation: Oak, hickory, sugar maple and beech. Use: The level to moderately sloping soils are cleared and used for corn, oats, wheat, and legume-grass mixtures. The steeper areas are used for permanent pasture or farm woodlots. Soil Management Group: 3a Distribution: Southern Michigan and northern Indiana. Widely distributed in large and small bodies. Type Location: Ionia County, Michigan Series Established: Hillsdale County, Michgan 1923. 107 Source of Name: County in Michigan National Cooperative Soil Survey - UOSOA. Reviewed for class use. Not an official series description. Classification is tentative. ORDER: Alfisol SUBORDER: Udalf GREAT GROUP: Hapludalf SUBGROUP: Typic Hapludalf FAMILY: Coarse—loamy, mixed, mesic Draft Subject to Review 108 Spinks Series Established Series Spinks series comprises well-drained soils developed in calcareous or neutral loamy sands, sands, or fine sands. Spinks soils have a pH above 5.6 in the sola instead of medium to strongly acid sola of the Coloma soils, thus Spinks soils are similar to Coloma soils except for reaction. Oakville soils have the same pH range in the sola as Spinks, but lack the thin textural B2t horizons (bands) of the Spinks soils. Stroh soils are the Mollisol intergrade to Alfisols. Oshtemo soils have a finer-textured sola and are underlain at depths of more than 42 inches by neutral or calcareous, stratified sands and fine gravel. Plainfield soils lack the textural B2t horizons (bands) within 60 inches found in Spinks but are medium to strongly acid in the sola. In Chelsea soils, the bands are below 40 inches. Soil Profile: Ap O-7: A2 7-20" BZt 20-23" Series of A'2 and B'2t horizons 23-50" Cl 50"+ Spinks loamy sand Loamy Sand: brown (lOYR 5/3) very dark grayish brown (lOYR 3/2), or dark grayish brown (lOYR 4/2); very weak, medium, granular structure; very friable, neutral to medium acid; abrupt smooth boundary. 6 to 12 inches thick. Loamy Sand or Sand: brown (lOYR 5/3) or yellowish brown (lOYR 5/4); very weak, medium, granular to single grain structure; very friable to loose; neutral to medium acid; abrupt wavy boundary. 8 to 30 inches thick. Sandy Loam or Fine, Loamy Sand: brown (7.5YR 4/4), strong brown (7.5YR 5/6) or dark yellowish brown (lOYR 4/4); weak, fine to medium, subangular blocky structure; very friable; slightly acid to neutral; abrupt wavy boundary. 1/2 to 8 inches thick. The A'2 parts of the horizon are Pale brown (lOYR 6/3) or light yellowish brown (lOYR 6/4) sand, while the B'2t parts of the horizon are strong brown (7.5YR 5/6), or dark yellowish brown (lOYR 4/4) sandy loam or fine, loamy sand B'2t horizon; the B'2t horizons which occur as thin (1/4 to 4 inches thick) bands or lenses are often wavy and discontinuous; A'2 horizons have single grain structure; while the B'2t horizons have weak, fine to medium, subangular blocky structure; mildly alkaline to slightly acid; 20 to 40 inches thick. Sand, Loamy Sand, or Fine Sand: pale brown (lOYR 6/3); single grain structure; loose; neutral to calcareous. 109 Range in Characteristics: Loamy fine sand, loamy sand, and sand types have been mapped. The depth to the first B2t horizon ranges from 15 to 42 inches. The thickness, number, and continuity of the B'2t horizons varies considerably in short horizontal distances. The thickness of the B'2t horizons, separated by A'2 horizons in the A'2 and B2t horizon varies from 1/4 to 8 inches in thickness, with the cumulative thickness greater than six inches. Where Spinks soils grade toward Oshtemo soils the thickness of the individual B2t horizons, and the combined thickness of the B2t bands approaches 10 inches. Where Spinks soils grade toward Coloma soils the pH of the sola is medium acid and the C1 horizon is neutral to mildly alkaline but not calcareous. Colors refer to moist conditions. Topography: Gently sloping to steep areas on moraines and outwash plains. Drainage and Permeability: Well-drained. Surface runoff is slow to very slow. Permeability is rapid to very rapid. Native Vegetation: Oaks and Hickory Use: Forage crops and pasture, with variable acreage in corn, wheat, oats, and soybeans. Some areas are in orchards, especially in south- western Michigan near Lake Michigan. Many areas are still in second- growth forest. Distribution: Southern Michigan and Northern Indiana. Type Location: NE 1/4 of SE 1/4 Sec. 24, T6N, R7W, Ionia County, Michi- gan. Series Established: Lenawee County, Michigan, 1955. Source of Name: Community in Berrien County, Michigan. Remarks: Spinks soils were formerly mapped as Coloma or Hillsdale soils in Michigan and as Coloma or Plainfield soils in Indiana. National Cooperative Soil Survey--USA Reviewed for class use. Not an official soil series description. Placement is tentative. ORDER: Alfisol SUBORDER: Udalf GREAT GROUP: Hapludalf SUBGROUP: Psammetic Hapludalf FAMILY: Sandy, mixed, mesic. 110 Draft Subject to Review Traverse Series Established Series The Traverse series are well to moderately well drained soils developed in medium acid to neutral sandy loams to loam materials. Traverse soils occupy depressions and old abandoned drainageways that are largely of glacial origin. Traverse soils are associated with McBride and Montcalm soils. Echo soils have profiles similar to Traverse, but are developed in sands to loamy sand materials. Pennock soils are Alluvial soils developed in sandy loam, loam, or silt loam materials and are subject to flooding and deposition of additional alluvium. Soil Profile: Traverse sandy loam Ap 0-7" Sandijoam: very dark brown (lOYR 2/2); weak, fine, granular structure; very friable; medium acid; abrupt smooth boundary. 6 to 10 inches thick. Al 7-20" Sandy Loam: very dark grayish brown (lOYR 3/2); weak, fine, subangular blocky structure; very friable; medium acid; abrupt wavy boundary. 6 to 15 inches thick. A'lb 20-29" Sandy Loam: black (lOYR 2/1); weak, fine, granular structure; very friable; medium acid; abrupt wavy boundary. 3 to 10 inches thick. B'2 29—42" Loamy Sand: dark yellowish brown (lOYR 3/4); very weak, fine, subangular blocky structure; very fri- able; medium acid; abrupt irregular boundary. 10 to 16 inches thick. A'2 42-44" Loamy Sand: brown (lOYR 5/3); massive; very friable; medium acid; abrupt irregular boundary. 1 to 3 inches thick. A'2 and 44-66" Brown (lOYR 5/3) loamy sand; single grained; loose B'2t vdfixfl: represents the A'2 horizon; dark brown (7.5YR 4/4) sandy loam; massive to weak fine subangular blocky structure; friable which represents the BZt horizons, the B'2 horizons occur as thin and often discontinuous bands, separated by A'2 horizons; medium acid; clear to abrupt wavy boundary. 10 to 30 inches thick. C 66"+ Loamy Sand to Sandy Loam: pale brown (lOYR 6/3), with many, common, faint brownish yellow (lOYR 6/6) and yellowish brown (lOYR 5/6) mottles; massive; very friable; mildly alkaline. 111 Range in Characteristics: Sandy loam, loam, and loamy sand types have been recognized. The surface soil is dark yellowish brown (lOYR 4/4) in some areas, especially where there has been relatively recent deposition. Depth to mottling is as little as 20 inches in some areas. Colors of the B horizons grade to the 7.5YR hue. The total thickness of the textural bands in the A'2 and B'2 horizon ranges from about 1/3 of the horizon to only an occasional thin band. Colors refer to moist conditions. Topography: Depressions and old glacial drainageways. Drainage and Permeability: Well to moderately well drained. Runoff is very slow. Permeability is moderately rapid. Vegetation: Chiefly northern hardwoods. Use: A considerable proportion is in permanent pasture. Soil Management Group: L-3b Distribution: Central and northern Michigan. Type Location: NE 1/4 of SE 1/4, Section 8, T20N, R8W, Osceola County, Michigan. See Osceola soil survey reports. Series Established: Grand Traverse Project Area, Grand Traverse County, Michigan, 1940. National COOperative Soil Survey--USA Placement is tentative ORDER: Mollisol SUBORDER: Udoll GREAT GROUP: Hapludoll SUBGROUP: Cumulic hapludoll FAMILY: Coarse-loamy, mixed, frigid 112 Draft Subject to Review Tuscola Series Established Series The Tuscola series comprises moderatly well drained soils which developed in stratified silts, very fine sands, and fine sands in southern Michigan. Tuscola series is the moderately well drained mem- ber of the drainage sequence that includes the well-drained Sisson, somewhat poorly drained Kibbie, and the poorly to very poorly drained Colwood soils. The moderately well drained Celina soils are developed from loam or silt loam till with finer-textured Bt horizons, stronger grade of structure and usually a more acid sola than Tuscola soils. The well to moderately well drained Gagetown soils which developed in materials similar to those oftflmaTuscola soils, are calcareous at or near the surface and have a much thinner sola than the Tuscola soils. The well to moderately well drained Shinrock soils deve10ped from stratified, lacustrine fine silts and silty clay loams and are finer textured throughout the profile thantiMLTuscola soils. The moderately well drained Arkport soils developed from stratified lacustrine loamy find sands and fine sandy loams and are coarser textured throughout the profile than Tuscola soils. Bohemian soils are the northern analog of the Tuscola soils. Soil Profile: Ap 0-9" Fine Sandy Loam: dark grayish brown (lOYR 4/2) or very dark grayish brown (lOYR 3/2); weak, coarse, granular structure; friable; slightly acid; abrupt smooth bound- ary. 7 to 10 inches thick. A2 9-13" Fine Sandy Loam: yellowish brown (lOYR 5/4) or brown (lOYR 5/3) with grayish brown (lOYR 3/2) organic coat- ings on some ped faces and in worm casts; weak, fine, subangular blocky to weak, thin, platy structure; friable; slightly acid to neutral; clear smooth bound- ary. 3 to 6 inches thick. B21t 13-24" Fine Sandy Loam or Loam: dark yellowish brown (lOYR 4/4) with a few peds coated with dark grayish brown (lOYR 4/2); weak to moderate, medium, subangular blocky structure; friable; very thin discontinuous clay flows; slightly acid to neutral; gradual smooth boundary. 8 to 17 inches thick. B22t 24-34" Very Fine Sandy Loam or Silt Loam: brown (lOYR 5/3) with common, medium, faint yellowish brown (lOYR 5/8) and gray (lOYR 5/1) mottles; weak, medium, subangular blocky structure; firm; very thin discontinuous or patchy clay flows; slightly acid to neutral; clear smooth boundary. 6 to 14 inches thick. 113 B23tg 34-40" Silt Loam or Silts: grayish brown (lOYR 5/2) with common, medium, distinct yellowish brown (lOYR 5/4-5/8) mottles; weak; medium, subangular blocky to weak, thin, platy structure; firm; very thin patchy clay flows; neutral; clear wavy boundary. 6 to 12 inches thick. B3g 40-44" Very Fine Sandy Loam: grayish brown (lOYR 5/2) mottled with yellowish brown (lOYR 5/6-5/8) and gray (lOYR 5/1) mottles are common, medium, and distinct; massive (stratified) to very weak, coarse, subangular blocky structure; friable; mildly alkaline; abrupt wavy boundary. 1 to 10 inches thick. 44-55" Silts and Very Fine Sands: gray (10 YR 5/1) mottled with grayish brown (lOYR 5/2), and dark brown (7.5YR 4/4) mottles are common, medium, and distinct, massive (stratified); friable; calcareous. Range in Characteristics: Fine sandy loam, loam, and silt loam types have been mapped. The texture of the B horizons is variable commonly within short distances. The range includes fine sandy loam, clay loam, silty clay loam, or silt loam. Depth to mottling ranges from 16 to 30 inches. The C horizon occurs at 24 to 46 inches or more in depth. Texture of the C horizon ranges from stratified silts and very fine sands to dominantly silts or dominantly very fine sands. Thin strata of loam and silty clay occur in the profile in some areas. Colors refer to moist conditions. Topography: Nearly level to gently sloping areas on lake plains and deltas. Drainage and Permeability: Moderately well drained. Runoff is slow on nearly level areas, medium on sloping areas. Permeability is moder- ate. Natural Vegetation: Sugar maple, oaks, beech, elm, and basswood. Use: Largely under cultivation to corn, soybeans, wheat, oats, and legume-grass mixtures. Soil Management Group: 2.5a Distribution: Southern Michigan, northwestern Ohio, and probably southeastern Wisconsin and northern Indiana. Type Location: Lenawee County, Michigan, NW 1/4 of NW 1/4 of NW 1/4 of Sec. 14, T7C, R5E. Series Established: Tuscola County, Michigan, 1926. '114 Source of Name: County in Michigan. National COOperative Soil Survey--USA Reviewed for temporary use in series file. Not an official soil series. Classification is tentative. ORDER: Alfisol SUBORDER: Udalf GREAT GROUP: Hapludalf SUBGROUP: Hapludalf FAMILY: Fine loamy, mixed, mesic. HICHIGRN STRTE UNIV. LIBRQRIES llillllll 90 I III! lllllfl "ll 9 312 31041 305