bluuebunny/crossref_metadata_2025 huggingface dataset:
Carbon Transformations in the Land Areas Receiving Organic Wastes in Relation to Nonpoint Source Pollution: A Conceptual Model
Authors: Reddy K. R. , Khaleel R. , Overcash M. R.
Published: July 2010

A simple conceptual model based on current literature data was developed to describe organic carbon (C) loss from land areas receiving organic wastes. The model considers the decomposition of substrate C as represented by the evolution of CO2. Decomposition of wastes was described in two or three phases, assuming first‐order kinetics at each phase. The fraction decomposed at each phase was determined graphically. Rapid decomposition of an easily decomposable C fraction in Phase I and II was followed by the decomposition of more resistant C fraction(s). For plant residues, the amount of C decomposed in Phase I was significantly related to the log C/N ratio of the residue, whereas, a similar relationship was not observed for animal wastes. Decomposition rates were about 6 to 10 times faster during Phase I and II decomposition, as compared to Phase III decomposition. Kinetic rate constants, calculated at each phase of decomposition were adjusted for the soil temperature, soil moisture, and method of application. For plant residues, simulated results were in close agreement with observed results. No field data are available to test the complete model for animal waste decomposition. Transport of soluble C (easily decomposable C fraction) in leaching and surface runoff was discussed in the paper. Equations were presented to calculate the transport of waste particles (resistant C fraction) and sediment‐associated C in the runoff water.

Future research needs identified include (i) a better understanding of C transformations; (ii) decomposition of individual C species, such as water‐soluble C, cellulose, and lignin; (iii) a relationship between soluble and particulate C fractions in runoff water; (iv) mechanisms involved on the mode of C transport along with percolating water or in runoff water; and (v) extensive testing of existing models.
Areal, Vertical, and Temporal Differences in Ground Water Chemistry: II. Organic Constituents
Authors: Junk G. A. , Spalding R. F. , Richard J. J.
Published: July 2010

Selected organic components in samples collected from monitoring wells and from surface water are shown to follow definite areal, vertical, and temporal trends in concentration. Atrazine (2‐chloro‐4‐[ethylamino]‐6‐[isopropylamino]‐s‐triazine), alachlor (2‐chloro‐2′ ,6′ ‐ diethyl‐N‐[methoxymethyl]acetanilide) and dieldrin (1,2,3,4,10,10‐hexachloro‐exo‐6,7‐epoxy‐1,4,4a,5,6,7,8,8a‐octahydro‐1,4‐endo, exo‐5,8‐dimethanonaphthalene) were measured in 64, 35, and 35 water samples, respectively. The atrazine amounts ranged from < 0.01 to 88 µg/liter. Peak concentrations were observed in shallow well water downgradient from irrigated fields at the end of the irrigation season. The areal and vertical distributions of atrazine are closely associated with those of nitrate‐nitrogen (NO3‐N), which was measured as an indicator of deep percolation from irrigated croplands. However, temporal variations in atrazine concentrations suggest that it is a nonconservative constituent of ground water. Alachlor and dieldrin amounts were extremely low, being less than 0.1 µg/liter in all but one water sample which was taken from a well located in an excessively well‐drained area. Dissolved organic carbon (DOC) was measured in 95 water samples and the amounts ranged from 0.2 to 4.8 mg/liter. Maximums occurred in shallow wells and there were no seasonal associations with either atrazine or NO3‐N. The DOC data suggest percolation from the unsaturated zone and partial removal from solution during vertical transport within the saturated zone.
Tidal Freshwater Marsh Establishment on Dredge Spoils in the Columbia River Estuary
Authors: McVay Michael E. , Heilman Paul E. , Greer David M. , Brauen Stanton E. , Baker Aaron S.
Published: July 2010

A study of marsh establishment through seeding and transplanting of tufted hairgrass [Deschampsia cespitosa (L.) Beauv.] and slough sedge (Carex obnupta Bailey) on sandy dredge material in an intertidal location in the Columbia River Estuary is reported. The experiment included treatments with single and split applications of a mixed N, P, and K fertilizer. Survival and growth of plants and N, P, and K concentrations in plant tissues are presented.

Survival and biomass production differed significantly with respect to elevation with few plants of either species surviving after the first winter below 0.7 m above Mean Lower Low Water (MLLW). The best growth of tufted hairgrass transplants was in upper elevations (Average about 1.9 m above MLLW), but satisfactory stands were obtained down to about 0.9 m above MLLW. The best growth of slough sedge was at middle elevations (about 1.1 m above MLLW) with satisfactory growth down to about 0.8 m above MLLW. Direct seeding was not a satisfactory means for establishing these species, although natural seeding of tufted hairgrass began to occur in the second year of the plantings in areas protected and stabilized by the transplants.

Fertilizer significantly increased growth of tufted hairgrass during both growing seasons, particularly at the upper tier. With slough sedge, except for a slight increase in the number of culms, fertilizer had no significant effect on growth in either year.
The Influence of Relative Humidity on Direct Sulfur Dioxide Damage to Plant Sexual Reproduction
Authors: Murdy William H. , Ragsdale Harvey L.
Published: July 2010

Results of in vivo experiments with Geranium carolinianum L. showed that sulfur dioxide (SO2) damaged sexual reproduction (in terms of decreased seed set) when relative humidity (RH) was 80% or above, but not when RH was 70% or below. Relative humidity alone, if 80% or higher, damaged sexual reproduction; the addition of SO2 increased the damage. A high SO2 dosage of 1.5 ppm/7 hours at 50% RH caused leaf injury, but decreased percent seed set < 5%, whereas a low SO2 dosage of 0.2 ppm/7 hours at 90% RH decreased percent seed set by 32% without visible leaf injury. At an SO2 dosage of 0.4 ppm/7 hours administered during anthesis, percent seed set was virtually identical with the control at 70% RH, 35% below the control at 80% RH, and 68% below the control at 90% RH.
Residual Nitrogen Availability from Soils Treated with Sewage Sludge in a Field Experiment
Authors: Stark S. A. , Clapp C. E.
Published: July 2010

In this experiment we determined the residual nitrogen availability from sewage sludges applied to a Hubbard sandy loam soil. In Study I, three sludge types—anaerobically digested (119, 237, and 466 metric tons/ha), aerobically digested (244 metric tons/ha), and mixed primary‐settled and waste‐activated (493 metric tons/ha)—were applied over a 3‐year period. Soil samples were collected from the field experiment 2 years after the final sludge application. Study II samples were obtained from plots of a field experiment in which an anaerobically digested sludge had been applied (63, 125, and 200 metric tons/ha) 4 years earlier.

Several biological and chemical characteristics were examined as indexes of N availability. Cumulative N mineralization during aerobic incubation was approximately linearly related to time1/2 for all treatments. Index values for Study I samples varied widely, hut in general, reflected the quantity of sludge added: total soil C (1.05 to 4.66%), total soil N (0.092 to 0.608%), indigenous inorganic N (12 to 266 µg/g), N mineralized during 52 weeks of aerobic incubation (87 to 884 µg/g) and during 16 weeks of anaerobic incubation (14 to 525 µg/g), nitrogen mineralization potential, No (126 to 1,010 µg/g), and autoclave‐extractable N (76 to 441 µg/g). The sludge application rate was more important than the sludge type in affecting N mineralization. The sludge‐treated soils from Study II had lower and less varied index values than those from Study I.

The evaluation of N‐availability indexes was based on the degree of correlation between the index values and N uptake by irrigated, field grown maize (Zea mays L.) (Study I) or sorghum‐sudangrass (Sorghum vulgare sudanese L., var. ‘Trudan V’) grown in the greenhouse (Study II). Each index was useful in determining relative differences of N availability for this soil having received greatly differing organic N treatments from sewage sludge. Nitrogen mineralized during short and long periods of incubation correlated with plant N uptake equally well. The chemical indexes of N availability were as reliable as more time‐consuming incubation procedures for determining the N‐supplying capacity of soils.
Copper and Lead Levels in Crops and Soils of the Holland Marsh Area—Ontario
Authors: Czuba M. , Hutchinson T. C.
Published: July 2010

A study has been made of the occurrence, distribution, and concentrations of the heavy metals copper (Cu) and lead (Pb) in the soils crops of the important horticultural area north of Toronto known as the Holland Marsh. The soils are deep organic mucks (> 85% organic mtter), derived by the drainage of black marshland soils, which has been carried out over the past 40 years. A comparison is made between the Pb and Cu concentrations in undrained, uncultivated areas of the Marsh and in the intensively used horticultural area. Analyses show a marked accumulation of Cu in surface layers of cultivated soils, with a mean surface concentration of 130 ppm, declining to 20 ppm at a 32‐cm depth. Undrained (virgin) soils of the same marshes had < 20 ppm at all depths. Lead concentrations also declined through the profile, from concentrations of 22 to 10 ppm. In comparison, undrained areas had elevated Pb levels. Cultivation appeared to have increased Cu, but lowered Pb in the marsh. Copper and lead levels found in the crops were generally higher in the young spring vegetables than in the mature fall ones. Leafy crops, especially lettuce (Lactuca L.) and celery (Apium graveolens), accumulated higher Pb levels in their foliage compared with levels in root crops. Cultivation procedures, including past pesticide applications and fertilizer additions, appeared to be principal sources of Cu. Mobility from the soil and into the plant for these elements in the marsh muck soils is discussed.
Environment in Open‐top Field Chambers Utilized for Air Pollution Studies
Authors: Olszyk D. M. , Tibbitts T. W. , Hertzberg W. M.
Published: July 2010

Cylindrical open‐top chambers were established in an alfalfa field (Medicago sativa L.) 50 km north of Madison, Wis. Chambers were set up with and without activated charcoal filters. Environmental measurements were made at different times during the summer growing season. The environment of open‐top chambers was found to differ somewhat from open areas. Light intensity was as much as 20% lower, temperature increases as great as 2°C were measured, and evaporative water loss was 10% less in the chambers than open areas. The filtered and nonfiltered chambers had slightly different environments as a result of variations in air flow rates and dust accumulation in the plenums of the two types of chambers. Across the chambers, there was a gradient in light intensity and evaporative water loss, but no significant gradient in temperature or air velocity. There was no evidence of pollution injury to alfalfa in this study.

The environmental changes in chambers were shown to cause differences in plant growth which likely caused changes in pollution sensitivity of plants within the chambers. However, it is postulated that this altered plant growth would likely not result in either a consistent increase or decrease in sensitivity at different times during the growing season or in different years. Thus, when open‐top chambers are utilized for the determination of crop yield losses, assessments should be based on studies conducted over several different growing periods.
Effectiveness of Land Application for Phosphorus Removal from Municipal Waste Water at Manteca, California
Authors: Iskandar I. K. , Syers J. K.
Published: July 2010

The concentrations of dissolved inorganic phosphate (DIP) in soil solution collected at 0.8 and 1.6 m in soils which had received municipal waste water for 4 and 13 years ranged from 7.3 to 13.9 µg P/ml. In some cases, these concentrations were higher than that in the added waste water. Sorption studies Indicated that the ability of soils from the control site to remove added P from solution was low. Waste water addition caused a substantial decrease in the P sorption capacity of surface soils and a marked change in isotherm shape from a curvilinear to an essentially linear isotherm. Sorption capacity generally increased down the profile to 60 cm on the treated sites. Only a small proportion of the total P accumulated from waste water addition was in the organic form. Large amounts of P were extractable by 10−2M CaCl2, particularly in the upper 45 cm of the profiles receiving waste water. Although lack of crop removal of P and a high infiltration rate may be partly responsible for the poor performance of the Manteca system in terms of P removal from waste water, the very low P sorption capacity of the soil is regarded as the major factor.
The Effect of Soil on the Renovation of Acid Coal Mine Drainage Water
Authors: Cronce Richard C. , Kardos Louis T. , Ciolkosz Edward J.
Published: July 2010

This study was initiated to determine under field conditions the feasibility of using soil as a medium for the renovation of acid mine drainage water. Acid water from a stream was applied weekly at three levels (0, 12.5, and 25 cm/week) to an unlimed and a limed (20 metric tons/ha) floodplain soil. Soil water samples were collected weekly at soil depths of 25, 75, and 130 cm. The soil water samples and the acid water were analyzed for pH, total acidity, Al, Fe, Mn, K, Ca, Mg, Na, and SO4. The effect of liming, levels of acid water irrigation, and depth in the soil profile on the soil water quality were determined.

Initially both the unlimed and limed areas had considerable capacity for renovating the applied acid water. However, with time, lower pH values and higher levels of acidity, Al, Fe, and Mn were found at the 25‐ and 75‐cm soil depths in the unlimed areas. When the soil was limed, the soil water at the 25‐cm depth was nearly neutral or alkaline throughout the study and practically devoid of Al, Fe, and Mn. At the 130‐cm depth on both unlimed and limed areas the pH, total acidity, Al, Fe, and Mn of the soil water remained relatively unchanged even after 525 cm of acid water had been applied. Growth of ryegrass and tall fescue was not adversely affected by irrigation with the acid water, but was significantly increased by liming. Only the tall fescue yielded significantly more with increased levels of acid water irrigation.
Differences Among Some North American Soils in the Rate of Reaction with Phosphate
Authors: Barrow N. J.
Published: July 2010

The results of C. G. Enfield and B. E. Bledsoe for the reaction between phosphate solutions and 25 North American soils were re‐examined by plotting log concentration against log‐time. This showed that the soils fell into two distinct groups. For most calcareous soils, widely differing initial concentrations of phosphate all tended to slowly decrease to a common concentration. This suggested that concentration was controlled by a solubility product. The second group was mostly noncalcareous. For these, the changes in concentration were closely described by an equation in which the effects on adsorption of both concentration and time were described by exponent terms. In contrast to previously studied Australian soils, there were large differences between the soils in the values of the two exponent terms. These reflect differences between the soils in the way they respond to increases in concentration of phosphate and to increases in period of reaction. These differences would be important in determining the amount of phosphate that could be stored by these soils. Values for the two exponents, over the range of soils, were correlated. The correlation appeared consistent with other published values.
Effects of Topsoil Thickness and Nitrogen Fertilizer on the Revegetation of Coal Mine Spoils
Authors: Mc Ginnies William J. , Nicholas Paula J.
Published: July 2010

A field study was established at a coal mine site in northwest Colorado to measure the effects of 0‐, 10‐, 20‐, 30‐, and 46‐cm depths of topsoil (a fine, montmorillonitic Typic Argiboroll) on establishment, percent stand, and species composition of a seeded stand. Percentage stand increased linearly from 16.4% on the 0‐cm topsoil treatment to 49.1% on the 46‐cm treatment by the second growing season. A greenhouse study using topsoil and spoil from the same area evaluated the same topsoil depths with respect to their effects on herbage and root production of intermediate wheatgrass (Agropyron intermedium) and wheat (Triticum aestivum). Herbage and root production of both species increased linearly with increasing topsoil thickness. Herbage production of wheat was, on the average, 32% greater than that of intermediate wheatgrass; however, root production of intermediate wheatgrass was 78% greater than wheat when grown in topsoil and 145% greater when grown without topsoil in spoil alone. A 112 kg N/ha fertilizer treatment increased biomass (herbage and roots) of intermediate wheatgrass by 74% over similar unfertilized treatments. When 15 cm of topsoil was mixed with 15 cm of spoil (total thickness of the topsoil mixture was 30 cm) in the greenhouse, herbage and root production of intermediate wheatgrass were the same as when grown in 15 cm of topsoil alone.
The Oxidation of Arsenite by Aquatic Sediments
Authors: Oscarson D. W. , Huang P. M. , Liaw W. K.
Published: July 2010

Sediments from five lakes in southern Saskatchewan, Canada, oxidize As(III) (arsenite) to As(V) (arsenate). The oxidation is not affected by flushing N2 or air through the sediment suspensions, nor does the addition of HgCl2 to the system eliminate the conversion of As(III) to As(V). The oxidation is an abiotic process with microorganisms playing a relatively minor role in this system. Because As(III) is more toxic and sorbed to a lesser extent by sediments than As(V), the suspended and bottom sediments may potentially alleviate the toxicity of As(III) through abiotic oxidation in aquatic environments.
The Potential for Ground Water Contamination from Septic Effluents
Authors: Hagedorn C. , Mc Coy E. L. , Rahe T. M.
Published: July 2010

Large populations in both rural and urban areas rely on septic tank soil‐absorption treatment systems as the principal disposer of domestic waste materials. Potential ground water pollutants, including pathogens, are removed from percolating drainfield effluents by microbial activity, soil filtration, and adsorption, preventing their entry into ground water. There is accumulating evidence, however, that water supplies in many areas of the United States are receiving increased pollution loads, and the source has frequently been traced to contaminated recharge waters. This paper reviews literature on both the conditions present where conventional disposal systems malfunction, and the mechanisms by which incompletely treated septic wastes may come into contact with various water resources. Current information regarding the function of a drainfield system and an examination of data from recent microbiological investigations on conditions necessary for the removal of enteric organisms from effluent waters is also included. Research needs are addressed with emphasis on problem areas which need further investigation in order to develop safe guidelines for determining the suitability of septic tank systems in relation to regional soil‐water conditions.
The Effect of Beef Feedlot Runoff on the Nitrate‐Nitrogen Content of a Shallow Aquifer
Authors: Terry R. V. , Powers W. L. , Olson R. V. , Murphy L. S. , Rubison R. M.
Published: July 2010

A field experiment was performed to determine effects various application rates of beef feedlot runoff had on the NO3‐N concentration of a shallow aquifer. A randomized complete block design with 3 blocks and 5 application rates (0.0, 2.5, 5.1, 7.6, 10.2 cm) was used each irrigation. Treatments were applied after precipitation had produced sufficient runoff. A dual well system (shallow and deep wells in each plot) was sampled every month for 3 years and the collected water was analyzed for NO3‐N. Graphical and statistical examinations of the data indicated shallow well NO3‐N concentrations in block 3 were high (up to 46 mg/liter) and extremely variable. Statistical analyses performed on means from 12 quarters showed only one significant treatment effect in the seventh quarter. However, during most quarters the highest application rate showed the lowest concentration of NO3‐N in the ground water. The dual well system revealed parallel fluctuations in shallow and deep wells, indicating that some changes in NO3‐N resulted from a regional phenomenon rather than from applied treatments.
Chemical Treatments of Soil to Decrease Radiostrontium Leachability
Authors: Spalding Brian P.
Published: July 2010

The leachability of radiostrontium from radioactive waste and through soil is one of the most salient problems with shallow‐land burial as a disposal method. The continuous leaching of buried waste at the Oak Ridge National Laboratory (ORNL), for periods up to 30 years, by lateral ground water flow has led to the contamination of surrounding soils and streams with 90Sr. The goal of the present investigation was to evaluate methods to effect either the in situ fixation or reduced leachability of 90Sr in soil. Small columns of three soils, collected from the solid waste disposal areas at ORNL, were labeled with 85Sr as a convenient tracer for 90Sr. After this labeling, but prior to leaching, the soil columns were percolated with equivalent amounts of sodium salt solutions of hydroxide, fluoride, carbonate, phosphate, silicate, or aluminate. Leaching was then initiated with 0.1N CaCl2 which was selected to qualitatively simulate ground water which contains Ca as the dominant dissolved cation. With two soils, high in indigenous exchangeable Ca2+, only 30–35% of the 85Sr could be leached from the carbonate‐treated columns. Presumably, the 85Sr was coprecipitated with the nascent CaCO3 formed during this treatment. In contrast, >98% of the 85Sr was readily leached from all untreated soils. Other anions fixed variable but generally less 85Sr than the carbonate treatment. Thus, sodium carbonate appears to have a potential application to immobilize 90Sr in situ in contaminated soil.
Effects of Municipal Waste Water on the Yield and Quality of Cotton
Authors: Day A. D. , Mc Fadyen J. A. , Tucker T. C. , Cluff C. B.
Published: July 2010

In 1974 and 1975, experiments were conducted near Buckeye, Arizona to study the influence of municipal waste water on the growth and yield of cotton (Gossypium hirsutum L.). Two sources of irrigation water were used: (i) pump water from local wells (control treatment) and (ii) municipal waste water and pump water in a 50:50 mixture.

Cotton irrigated with the waste water and pump water mixture grew taller with more vegetative growth than did cotton that was irrigated with pump water alone. When cotton was irrigated with the waste water and pump water mixture, the yields of seed cotton and lint cotton were higher than the yields from cotton irrigated with pump water. Cotton irrigated with waste water and pump water produced lint of the same quality as did cotton irrigated with only pump water.

Municipal waste water can be used effectively as a source of irrigation water and plant nutrients in the commercial production of cotton in Arizona and, possibly, in similar environments throughout the world. When municipal waste water is mixed with pump water that is high in total soluble salts, the salt content of the mixture is lowered and the quality of the irrigation water in the study area is improved.
Modeling Sewage Sludge Decomposition in Soil: II. Nitrogen Transformations
Authors: Hsieh Y. P. , Douglas Lowell A. , Motto Harry L.
Published: July 2010

Laboratory incubations were conducted to study N transformations in two sewage sludge‐soil systems. The duration of the lag phase of nitrification was related to the active organic C content and moisture level of the system. The N mineralization potential was found to be 30% and 38% of the organic N in the activated sludge and digested sludge respectively. The mineralization rate constant was 0.026 day−1 at 21°C which corresponded to a half life of 27 days. Moisture levels of 0.06 and 0.33 bars had no significant effect on the N mineralization rate. Denitrification might be an important pathway of N transformation in sewage sludge‐soil systems. Denitrification and nitrification could proceed either simultaneously or alternatively in the systems in an unsaturated condition. The N transformations of the sewage sludge‐soil systems were described in a model assuming either first or zero order kinetics. The model can predict the amount of NH4+, NO3−, NO1−, organic N, and their rate of production. The values from the model usually fit the observed values.
The Response of a Southern Appalachian Forest to Waste Water Irrigation
Authors: Brister G. H. , Schultz R. C.
Published: July 2010

The operational land treatment system at Unicoi State Park near Helen, Georgia was used for a period of 3 years to study the role of a mature Appalachian forest in renovating municipal waste water. Uptake of some of the nutrients in the waste water was occurring in the vegetation, but no systematic nutrient uptake by any one component of the stand was observed. Overstory trees failed to show any growth response to the irrigation in height or diameter at breast height (dbh), but did show increased stem diameter growth within the canopy. The irrigation was causing significant increases in diameter at 0.3 m and height of understory trees. A detailed stem analysis of 5 treated and 5 control white pine trees (Pinus strobus L.) from the mature overstory showed that upper stem diameter growth was increased significantly as a result of the irrigation. This stem volume response to waste water irrigation would not be detected had breast height diameter and total height been the only stem measurements taken. The irrigation is decreasing the biomass, the diversity, and the number of individuals of the ground vegetation.
Plant Growth and Trace‐Element Uptake on Acidic Coal Refuse Amended with Lime or Fly Ash
Authors: Jastrow J. D. , Zimmerman C. A. , Dvorak A. J. , Hinchman R. R.
Published: July 2010

Two commonly used revegetation species, ‘Kentucky 31’ tall fescue (Festuca arundinacea Schreb.) and ‘Lincoln’ smooth brome (Bromus inermis Leyss.), were grown for 60 days in pots containing coarse coal mine refuse (referred to as gob, pH = 3.5) amended with either lime or alkaline powerplant fly ash. Both species were also grown in pots containing a silt loam surface soil as a control. Morphological growth parameters were measured over time; dry weights and shoot/root ratios were determined at harvest. Concentrations of Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, V, and Zn in the plant shoots were determined by atomic absorption spectrophotometry. Plant growth of both species was not as good on either lime‐ or fly ash‐amended gob as it was on surface soil; however, more vigorous growth occurred on lime‐amended gob than on fly ash‐amended gob. Significant differences (p <0.05) in the tissue concentrations of Cd, Co, Fe, Hg, Mn, Pb, V, and Zn were found among the plants grown on the three substrates. Except for Hg and Pb, these elements were higher in plants grown on at least one of the amended‐gob substrates than in plants grown on surface soil. Significant substrate differences were not observed for Al, As, Cr, Cu, Ni, and Se. The tissue concentrations of some elements—notably Al, Cu, Fe, Mn, V, and Zn—were high enough in plants from one or more of tbe substrates to either approach or exceed concentrations which have been reported to be associated with toxic effects in some plant species.
Fertilizer Flux into Two Florida Lakes via Seepage
Authors: Fellows Charles R. , Brezonik Patrick L.
Published: July 2010

Excessive fertilization of a 4.8‐ha citrus grove with 900 kg N/ha resulted in leaching of nitrate through the soil and seepage of ground water with high nitrate levels into Lake Conway, Florida. A total of about 270 kg of N seeped into the lake from the single fertilization event, representing about 6% of the total applied fertilizer N. In comparison, seepage measurements at five other lake sites had much lower concentrations and fluxes of nitrate, even though three of the sites were located adjacent to fertilized agricultural or urban areas. Normal fertilization practices did not appear to enhance seepage fluxes of nutrients to lakes.
Joint Action of Sulfur Dioxide and Nitrogen Dioxide on Foliar Injury and Stomatal Behavior in Soybean
Authors: Amundson R. G. , Weinstein L. H.
Published: July 2010

Six cultivars of soybeans [Clycine max (L.) Merr.] were screened for susceptibility with respect to foliar necrosis after exposure to short‐term, relatively high concentrations of SO2 or SO2 in combination with NO2. In all screening trials (three), the combination of SO2 and NO2 produced less foliar injury than did the same concentration of SO2 singly.

Three of the six cultivars with differing susceptibilities to SO2, ‘Beeson’ (most sensitive), ‘Amsoy’ (intermediate), and ‘Hark’ (least sensitive), were grown to the 10‐trifoliate stage and were exposed for 4 hours to charcoal‐filtered air (control), 5,200 µg m−3 SO2 (2 ppm), 950 µg m−3 NO2 (0.5 ppm) or 5,200 µg m−3 SO2 plus 950 µg m−3 NO2. Again, necrotic lesions developed only on those plants exposed to 5,200 µg m−3 SO2 singly. The youngest fully expanded trifoliates on all three cultivars had the most leaf area damaged. Leaf resistance measurements were made on the upper and lower leaf surfaces of the eighth and ninth trifoliates on two of the six plants per cultivar exposed to each treatment. No changes in leaf resistances of the control plants or those exposed to 950 µg m−3 NO2 were measured. Leaf resistances increased somewhat during exposure to SO2, but they increased dramatically in plants exposed to the combination of SO2 and NO2. The antagonistic effects of SO2 and NO2 on the development of necrotic lesions reported in this paper can be explained at least partially by pollutant avoidance due to stomatal closure caused by the combination of the two pollutants.
Adsorption of Cadmium on Soil Constituents in the Presence of Complexing Ligands
Authors: Chubin R. G. , Street J. J.
Published: July 2010

The objective of this study was to evaluate the effect of natural and synthetic complexing agents on Cd2+ adsorption characteristics of metal hydroxides and silicate clay minerals. The solution pH at which 50% of the initial solution Cd2+ was adsorbed was 5.40, 7.00, 7.80, and 8.30 for Al(OH)3, Fe(OH)3, montmorillonite, and kaolinite, respectively. The presence of citrate (C6H5O73‐) depressed Cd adsorption on Al(OH)3, by approximately 25% in acidic solutions. The addition of EDTA (C10H16O8N2) depressed the Cd adsorption on both Al and Fe hydroxides, montmorillonite, and kaolinite in acidic and alkaline solutions. The water‐soluble organic fraction from sewage sludge enhanced Cd adsorption by both kaolinite and montmorillonite in alkaline solutions. The water‐soluble organic fraction from an organic soil (Terra Ceia muck) increased Cd adsorption by Fe(OH)3 only under acidic conditions.

Preliminary results indicated that considerations of Cd retention by soil constituents should include not only the aqueous chemistry of Cd and the surface chemistry of the adsorbent, but also the chemistry of natural and synthetic complexing agents. The interaction of Cd and various complexing agents can play an important part in determining the fate of this metal in the soil‐water‐plant environment.
Behavior and Transport of Microbial Pathogens and Indicator Organisms in Soils Treated with Organic Wastes
Authors: Reddy K. R. , Khaleel R. , Overcash M. R.
Published: July 2010

In a critical review of pathogen and indicator‐organism transformations and transport from land areas receiving organic wastes, microbial die‐off was described assuming first‐order kinetics. First‐order die‐off rate constants (k) were calculated from the literature data for various pathogens and indicator organisms. For indicator organisms average die‐off rates were 1.14 day−1 (0.08–9.1) for fecal coliforms, and 0.41 day−1 (0.05–3.87 day−1) for fecal streptococci. For pathogens, the average die‐off rates were 1.33 day−1 (0.21–6.93) for Salmonella, 0.68 day−1 (0.62–0.74 day–1) for Shigella sp., and 1.45 day−1 (0.04–3.69 day−1) for viruses, respectively. Die‐off rates increased approximately two times with a 10°C rise in temperature (5–30°C). Microbial die‐off increased with decrease in soil moisture and was minimum in a pH range of 6–7. Correction factors were presented to adjust the k values for the changes in temperature, moisture, and pH. Retention of pathogens and indicator organisms by soil particles was described assuming a linear isotherm. Retention of microorganisms increased with an increase in clay content of the soil.

Major transport processes reviewed were leaching and surface runoff for land areas receiving animal wastes, and pastures and rangeland watersheds where animals distribute waste directly on the land. Some of the important research needs identified include (i) mechanisms involved in the retention of bacteria and viruses by the soil; (ii) measurement of retention coefficients for some important pathogens and indicator organisms, as a function of physico‐chemical properties of soil; (iii) processes involved in the transport of bacteria and viruses along with the percolating water or in runoff water; and (iv) extensive testing of available models.
Vegetative Filter Treatment of Livestock Feedlot Runoff
Authors: Dickey Elbert C. , Vanderholm Dale H.
Published: July 2010

Four vegetative filters were installed on feedlots in central and northern Illinois. Two configurations were used: channelized flow and overland flow. After settling for partial solids removal, runoff was applied directly to the filters and allowed to flow from the inlet to the outlet section. Results from measurement analyses and sampling of influent, effluent, and surface flow at intermediate points were reported.

Most runoff events were infiltrated completely, resulting in no filter discharge. Runoff from larger events was partially discharged. Filters removed as much as 95% of nutrients and oxygen‐demanding materials from the applied runoff on a weight basis, and 80% on a concentration basis. Removal was directly related to flow distance or contact time with the filter. Channelized flow with greater flow depths required greater contact time or flow distance than shallow overland flow to achieve the same level of treatment.
Factors Affecting Radionuclide Availability to Vegetables Grown at Los Alamos
Authors: White G. C. , Hakonson T. E. , Ahlquist A. J.
Published: July 2010

A field study was conducted in 1977 on 238, 239Pu and 137Cs availability to zucchini squash (Curcurbita melopepo, hybrid seneca) and green bush beans (Phaseolus vulgaris, Landreths stringless) grown under home‐garden conditions in an area at Los Alamos National Laboratory used for treated radioactive liquid waste disposal. Radionuclide concentrations were measured as a function of tissue type, height above the soil, fertilization regime, and for the squash, food‐cleansing procedures. Analysis of variance procedures were used to analyze the data.

Ratios of the concentration of a radionuclide in oven‐dried vegetation to dry soil ranged from 0.0004 to 0.116 for the Pu isotopes, and from 0.051 to 0.255 for 137Cs. Fertilization with cattle manure reduced the Pu concentration ratios by 30% and 137Cs by 50%. Vegetative parts sampled within 20 cm of the ground surface were contaminated about four times as much as those parts growing further from the ground surface. About 65% of the contamination was removed by washing, indicating the presence of surficial contamination. The 50‐year radiation dose commitment to humans consuming vegetables from the garden plot would be less than 0.05 mrem and would be due almost entirely to 137Cs.
Effects of Sanitary Landfill Leachate on Some Soil Chemical Properties
Authors: Winant W. M. , Menser H. A. , Bennett O. L.
Published: July 2010

The treatment of leachate from sanitary landfills has become a serious problem for many communities because of rising concern for water quality and increased use of landfills for disposal of solid waste. The objective of this research was to test the value of using soils to decontaminate waste water from a landfill. Approximately 100 cm of leachate from a sanitary landfill was applied over a 6‐month period, after which soil samples were collected to a depth of 60 cm. Ammonium acetate was used to extract Ca, Mg, Na, K, Mn, Fe, Zn, and Sr, while P was extracted with a dilute double acid. At a soil depth of 0–5 cm Ca, Mg, Na, K, and Sr levels of ammonium acetate extracts markedly increased, while leachate irrigation did not significantly change Fe, Zn, P, and Kjeldahl N concentrations. Leachate irrigation increased soil pH from 4.7 to 5.8 at the 0‐ to 5‐cm depth and from 4.5 to 5.7 at the 15‐ to 30‐cm depth. Most elements were attenuated to some extent by the soil, but lime and fertilizer addition did little to influence soil absorptive capacity.
Characterization of Mercury in a Riverwash Soil
Authors: Harsh J. B. , Doner H. E.
Published: July 2010

The extent of cinnabar (α‐HgS) degradation in a riverwash soil polluted by Hg mining waste was evaluated by determination of persistent α‐HgS and Hg liberated from the mineral. The soil was sequentially extracted to determine soluble, exchangeable, manganese‐oxide‐associated, and free iron‐oxide‐associated Hg. DTPA, 0.5N NaHCO3, and 0.5N and 1.0N HCl were used to determine available, weakly organic‐bound, and strongly adsorbed Hg, respectively. Particle size and density separations using tetrabromoethane and Clerici's solution were employed to determine Hg in < 1.8, 1.8–2.9, > 2.9, < 4.0, and > 4.0 g cm−3 fractions of clay, silt, and sand separates. A thermal fractionation of the soil was used to measure Hg loss at temperatures from 25 to 450°C.

Only traces of Hg were recovered by the chemical extractants, implying that very little existed in an adsorbed or easily soluble state. More than 90% of the Hg was recovered in the > 4.0 g cm−3 fraction. This, along with thermal fractionation and x‐ray diffraction data, indicated that this Hg remained primarily in the α‐HgS form. Loss of Hg in the tetrabromoethane separations and at low temperatures during the thermal fractionation suggested that Hg in both the colloidal and lighter fractions was organically bound.
Effects of Drainage and Long‐Term Manure Application on Nitrogen, Copper, Zinc, and Salt Distribution and Availability in Soils
Authors: Kuo Shiou
Published: July 2010

Effects of drainage and long‐term manure application on nitrogen, copper, zinc, and salt distribution in soil profiles were examined for a field that had been receiving manure applications for more than 20 years. The field ranged from well‐drained Briscot loam to poorly drained Shalcar muck and was planted with corn (Zea mays L.) in 1979. Ten weeks after planting, soil and plant tissue samples were collected from five different sites, and were analyzed for N, Cu, and Zn. More NO3−‐N was present in the Briscot loam than in the Shalcar muck, but considerable amounts of exchangeable NH4+‐N were found in the latter soil, and the amounts also increased with depth. The latter trend paralleled accumulation of salts in the lower horizons of the muck soil. No excessive elevations of Cu and Zn due to long‐term manure applications were found in either soil.

Consistently lower total N, Cu, and Zn concentrations were found in leaf tissues of corn grown on the poorly drained muck soil than on the better‐drained loam soil. Poor soil aeration in the muck soil could have adversely affected the ability of corn to either absorb or translocate these elements. In addition, the low NO3−‐N levels and low DTPA (diethylenetriaminepentaacetic acid)‐extractable Cu and Zn from the poorly drained soils could also have reduced availability and uptake of these elements.
Removal of Phosphorus from Waste Water by Soil Under Aerobic and Anaerobic Conditions
Authors: Hill D. E. , Sawhney B. L.
Published: July 2010

Studies of the movement of fertilizer‐P and P added to soils in waste water have shown that P movement is extremely slow. But in cultivated soils with tile drains it has also been observed that reducing conditions caused by flooding can increase P mobility.

To determine the movement of P under aerobic and anaerobic conditions, a simulated waste water containing 12 µg/ml P was added to an isolated soil block two‐three times a week for 2.5 years in a field experiment. The fine sandy loam soil was underlain by bedrock at 72 cm and had a water table fluctuating between the 25‐ and 75‐cm depths during the experiment. Analyses of the effluent from the weep holes at different depths suggests that the waste water moved along preferred pathways in heterogeneous soil and produced breakthrough of P to ground water before all sorption sites were fully saturated with P. Also, anaerobic conditions produced during periods of high water table enhanced the mobility of P, thus increasing the transport of P to ground water in soils used for continued waste‐water treatment. Renovation of waste water over long periods of time reduces the P sorption capacity of a soil, while periodic resting regenerates sorption sites and increases the potential for additional P sorption.

Estimates of P retention based upon its concentration in influent and effluent solutions and bulk density of the soil show a reasonably good agreement with laboratory determination of P retained following waste‐water renovation. Data also show that most of the P retained is transformed into unavailable forms.
Foliar Uptake and Injury from Saline Aerosol
Authors: Grattan S. R. , Maas E. V. , Ogata Gen
Published: July 2010

Pepper (Capsicum annuum L. cv. California Wonder), soybean (Glycine max L. Merrill cv. Prize), and tomato (Lycopersicon lycopersicum L. Karst. ex Farw. cv. Heinz 1350) plants were exposed to saline aerosols until incremental salt deposition levels of 0.2, 0.4, 0.6, and 0.8 mg Cl− cm−2 of horizontal surface area were achieved. Foliar necrosis became evident on the 0.4 mg Cl− cm−2 treatments after 3, 7, and 8 days on tomatoes, soybeans, and peppers, respectively, in an environmental chamber that simulated early morning dew between 0100 and 0700 PST. Severity of injury increased with increasing salt deposition and time. Foliar absorption of Na+ and Cl− was linearly related to the amount of salt deposition on leaves. No injury symptoms were apparent on any species at any salt deposition level when relative humidity (RH) was maintained at approximately 70% during the same period. Similar results were obtained in a second experiment where treated tomato, soybean, and pepper plants were compared at treatments of 70 and 100% RH during predawn hours but without dew formation. The injury at 100% RH, however, was not as pronounced as when plants were exposed to dew.
Formation of N‐Nitrosodimethylamine During Treatment of Municipal Waste Water by Simulated Land Application
Authors: Greene Sarah , Alexander Martin , Leggett Daniel
Published: July 2010

N‐Nitrosodimethylamine was formed at a linear rate in Lake George sand and Arkport fine sandy loam amended with sewage, dimethylamine, and nitrite. The rates of formation were similar in the two soils. The amount that accumulated in the waste‐water‐amended Lake George sand under non‐percolating conditions was a linear function of the amount of precursors added, and 0.8% of the dimethylamine and 1.3% of the nitrite was recovered as the carcinogen. The extent of conversion was smaller when sewage containing the precursors was percolated through this soil. The extent of nitrosation was influenced by the moisture level of the soil.
Flooding and Landfill Gas Effects on Red and Sugar Maples
Authors: Arthur J. J. , Leone I. A. , Flower F. B.
Published: July 2010

Seedlings of two maple species, Acer rubrum L. (red maple) and Acer saccharum Marsh (sugar maple), tolerant and intolerant to flooded soils, respectively, were subjected to flooded and simulated landfill‐gas‐saturated soils in modified 88‐liter steel trash cans in order to determine if flood‐tolerant characteristics of woody species are also effective in protecting plants from the effects of anaerobically produced gases (chiefly CH4 and CO2) in former landfills. The composition of the simulated landfill gas mixture consisting of approximately 3% O2, 40% CO2, 50% CH4, and 7% N2 (typical of many landfills observed), and the control, consisting of approximately 20% O2, <1% CO2, 80% N, and 0% CH4, were monitored routinely during the course of the experiment. Results of the experiment, based on stomatal resistances to the diffusion of water vapor from the leaf surfaces of the two species and visual appearances, indicated that the flood‐tolerant species, red maple, was also more tolerant of landfill‐gas‐contaminated soil than was sugar maple, the more sensitive of the two to flooded soils.
Reducing Ground‐Water Pollution from Municipal Waste‐Water Irrigation of Rhodes Grass Grown on Sand Dunes
Authors: Vaisman I. , Shalhevet J. , Kipnis T. , Feigin A.
Published: July 2010

During 1978 and 1979 an effluent‐irrigation field experiment was carried out on a sand dune established with Rhodes grass (Chloris gayana Kunth) to determine the irrigation needs of the grass in relation to removal of nutrients from the water and prevention of groundwater pollution. The municipal effluent used had received secondary treatment in settling ponds.

It was found that irrigation of Rhodes grass with waste water (secondary effluent) on sandy dune soil may be considered an appropriate method for the treatment of secondary effluent. The method obtained at one and the same time, high production and the avoidance of ground‐water pollution, especially by nitrate and phosphorus.
PCBs in the Housatonic River: Determination and Distribution
Authors: Sawhney B. L. , Frink C. R. , Glowa W.
Published: July 2010

An understanding of the mechanisms for the transport of polychlorinated biphenyls (PCBs) as well as their reactions with sediments should help in developing strategies for removal and disposal of sediments in contaminated rivers. We have developed a convenient procedure, based on multiple linear regression of peak heights (or areas) from gas chromatograms, for estimating individual members (Aroclors) for the PCB group of chemicals. Analysis of the bottom sediments of the Housatonic River system along a 20‐km section revealed that the sediments contained Aroclors 1248, 1254, and 1260 in the ratio of 1.0:0.6:1.9. PCB concentrations were highly correlated with clay and organic matter, suggesting that fine particles consisting of clay‐organo complexes in the sediments may provide a primary means of retention and transport of PCBs. Laboratory sorption of PCBs by clay minerals, humic acid, and the river sediments further substantiate these conclusions.