bluuebunny/crossref_metadata_2025 huggingface dataset:
Runoff Water Quality as Affected by Surface‐applied Dairy Cattle Manure
Authors: Long F. Leslie
Published: July 2010

The effect of dairy cattle manure on runoff water quality was determined. The manure was surface‐applied to Coastal bermudagrass (Cynodon dactylon [L.] Pers.) on a Norfolk sandy loam with < 2% slope, at the rate of 45 metric tons/ha per year for 4 years in split applications. Manure applications slightly increased biochemical oxygen demand (BOD) values of runoff water; the maximum value was < 20 mg/liter and annual mean values were all < 10 mg/liter with no BOD buildup in the runoff water over the 4‐year period. Nitrate levels in runoff water were increased by the manure, but all annual mean values were below critical levels at < 8 mg NO3‐N/liter. During the first 2 years, about 30 kg/ha total N was lost in runoff, but < 6 kg N/ha was lost during the third and fourth years.
Herbicide Runoff from Upland Piedmont Watersheds—Data and Implications for Modeling Pesticide Transport
Authors: Leonard R. A. , Langdale G. W. , Fleming W. G.
Published: July 2010

Runoff and persistence of selected herbicides were studied on four small Piedmont watersheds in Georgia during four growing seasons. This is part of a study designed to provide data for developing and testing mathematical models for agricultural chemical transport. Seasonal runoff losses were determined relative to watershed management, herbicide type and persistence, mode of application, and time of runoff in relation to application timing. Seasonal losses were usually < 2% of the application, unless large runoff volumes were generated shortly after application. Average storm herbicide concentrations in runoff were correlated with herbicide concentrations at the 0‐ to 1‐ cm depth increment of the watershed soils at the time of runoff. Paraquat concentrations in runoff (predominantly sediment associated) were well correlated and positive with the product of soil herbicide concentration and sediment in runoff. Equations describing soilbased herbicide transfer to runoff were power functions with exponents near unity with the form: Y = a xb. Simple relationships such as those developed in this study along with hydrology and erosion/sediment models may he useful in predicting pesticide runoff potential when assessing relative impacts of management decisions. The next step would be to describe key management practices in terms of these coefficients and exponents.
The Effect of Soil‐added Cadmium on Several Plant Species
Authors: Miles L. J. , Parker G. R.
Published: July 2010

Several species (Andropogon scopanus, Shus radicans, Rudbeckia hirta, Anemone cylindrica, Monarda fistulosa, Poa pratensis, and Liatris spicata) native to northwestern Indiana were grown from seed in the greenhouse for 6 weeks. An uncontaminated sandy soil was utilized as the substrate with four levels of soil‐added Cd. The concentrations added ranged from 0 to 100 µg Cd/g soil and were comparable to surface soil Cd concentration levels found in the urban‐industrial region of northwestern Indiana.

Data on germination, survival, height, and dry weight were collected. Germination, survival, and weight were found to exhibit a negative response to increasing soil Cd concentration over all species. Height, however, was not found to be a consistently good indicator of Cd response. While overall species' differences were noted, no differences could be conclusively shown among the species for Cd tolerance, although there were indications that this was the case. All effects noted were of a low level for the soil‐added Cd concentrations utilized.
Factors Influencing the Volatilization of Mercury from Soil
Authors: Rogers Robert D. , Mc Farlane James C.
Published: July 2010

Mercury volatilization from soils amended to 1 ppm mercury with mercuric nitrate decreased substantially within 1 week after application. During the first week, 20% of the applied mercury was lost from a silty clay‐loam soil and 45% was lost from a loamy sand soil. Volatilization of Hg from the loamy sand soil resulted in a concurrent decrease in ammonium nitrate‐extractable mercury. Other work with sterile soil indicates that the volatilization was mediated by microorganisms.
Transformations of Carbon, Nitrogen, and Metals in Soils Treated with Waste Materials
Authors: Sommers L. E. , Nelson D. W. , Silviera D. J.
Published: July 2010

Intact soil cores were used to evaluate decomposition, NH3 volatilization, N transformations, and metal movement in soils treated with sewage sludges and antibiotic processing wastes. Soil cores were leached monthly with water and incubated for 1 year. An insignificant amount (<1%) of the NH4+‐N applied was lost through NH3 volatilization. The addition of wastes to five soils established that soil properties did not influence decomposition. In contrast, appreciable differences in decomposition were observed when different wastes were added to the same soil. Significant amounts of NO3− were leached from soils treated with antibiotic wastes, while essentially no NO3− leaching occurred in soils receiving sewage sludge, suggesting that denitrification and/or immobilization are major N loss mechanisms in soils treated with sewage sludge. Minimal amounts of P and metals were leached from sludge‐amended soils. Soil analysis indicated that the majority of the added Zn, Cu, Cd, Ni, and Pb remained in the zone of sludge incorporation (0–7.5 cm) with minimal or no movement into the 7.5‐ to 15‐cm soil depth.
Sediment and Nutrient Yield from Residential Construction Sites
Authors: Daniel T. C. , Mc Guire P. E. , Stoffel D. , Miller B.
Published: July 2010

Runoff from three residential construction site watersheds in southeastern Wisconsin was monitored for a 2‐year period. Automatic water quality monitoring equipment was established which sampled each event proportional to flow. Loading rates for sediment and nutrients were developed on an event basis and summed to produce annual loads.

Concentrations for suspended solids (SS), organic plus exchangeable N [(Or + Ex)‐N], and total P preceded and paralleled the flow rate during runoff events. With the exception of nitrate plus nitrite nitrogen (NO3 + NO2)‐N, the soluble water quality parameters were independent of flow. Commonly, the (NO3 + NO2)‐N concentration was 1.0 mg/liter and varied inversely proportional to flow. The most common concentrations of dissolved phosphorus and ammonium were 0.05 and 0.10 mg/liter, respectively.

Average sediment yield for the three single land use watersheds was 19.2 metric tons /ha per year. Concentrations of 60,000 mg/liter SS were observed for major events; 15,000 to 20,000 mg/liter were common for moderate events. Regression analyses of several independent variables identified flow (Q) as the single most important variable examined for explaining sediment load. Considered in combination, the product of flow and flow rate (Qqp) best explained sediment yield (r2 = 0.62).

Yields of contaminants from residential construction sites are inherently variable and site dependent. Strict extrapolation or comparison of results to other areas or existing literature values is difficult. However, when compared to runoff data from a simultaneous agricultural watershed investigation, the yield of contaminants from construction sites is considerably higher (19.2 vs. <1 metric ton/ha per year of sediment).
Decomposition of Anaerobically Digested Sewage Sludge as Affected by Soil Environmental Conditions
Authors: Terry R. E. , Nelson D. W. , Sommers L. E.
Published: July 2010

Microbial oxidation of organic components in anaerobically digested sludge is an important aspect of the fate of sludges in soils. The objectives of this study were to determine the effects of soil characteristics, sludge management procedures, and environmental conditions on the decomposition rate of sewage sludge in soils. Synthetic sewage sludge was prepared by anaerobically digesting a mixture of 14C‐labelled Candida utilis cells and inorganic salts. The sludge prepared was similar in composition to anaerobically digested municipal sludges. After incorporation into soil, decomposition of sludge was rapid during the first 28 days, but the decomposition rate was low and relatively constant for the remainder of the incubation period. At the end of 336 days of incubation, 46% of synthetic sludge organic 14C was evolved as CO2, suggesting that one fraction of anaerobically digested sludge was readily decomposable when added to an aerobic soil. However, the major portion of sludge organic matter was resistant to decomposition. Factors such as soil texture, pH, and moisture content had little effect on sludge decomposition rates. Decomposition was greatest in soil samples receiving surface‐applied sludge and in samples incubated at high temperature (30°C) as compared to samples having sludge incorporated or incubated at 21°C.
Acidification of Headwater Streams in the New Jersey Pine Barrens
Authors: Johnson Arthur H.
Published: July 2010

Sixteen years of stream pH data indicate acidification of two relatively undisturbed headwater streams of the New Jersey Pine Barrens. Average yearly stream pH decreased approximately 0.2 to 0.5 units in the two small streams that have long‐term records. Hydronium ion concentration is correlated with SO4 in the two headwater streams in approximately a 1:1 ratio by equivalents, suggesting that H2SO4 is an important source of the acidity. A decrease in precipitation pH over the period is suggested in the literature and may be responsible for the decreasing stream pH.
Physical Condition of a Davidson Clay Loam after Five Years of Heavy Poultry Manure Applications
Authors: Weil R. R. , Kroontje W.
Published: July 2010

Little information is available on how soil physical properties are affected by very heavy poultry manure applications often associated with concentrated poultry production. In this study, after 5 years of applying up to 110 metric tons of poultry manure/ha per year to corn plots, the physical condition of the manured plots differed markedly from that of the unmanured controls. During the spring the activity of soil invertebrates created a highly channelized and aggregated structure in the surface soil. Plowlayer bulk density was reduced by the poultry manure from 1.1 to 0.8 g/cm3 and the percentage water‐stable aggregates increased from 73 to nearly 94%. About half of the variability in bulk density could be accounted for by differences in soil organic matter contents. The manured plots were generally more moist in the plow layer, especially in spring and early summer when a perched water table at a depth of 20 cm was caused by a water‐repellent plowsole layer of partially decomposed manure. In the spring this layer resulted in infiltration rates on the manured plots as low as 0.02 cm/hour compared to a mean of 12.1 cm/hour on the controls. In November, the infiltration rate of the manured plots rose to 57 cm/hour due to the activities of earthworms. The manured plots held nearly 42% moisture at 0.1 bar tension as compared to 32% for the control plots. Incorporation of poultry manure by means other than moldboard plowing might avoid the creation of a plowsole manure layer which counteracts the potentially beneficial effects of the manure on soil structure and water‐holding capacity.
The Transfer of the Coccidiostat Clopidol to Lambs by Feeding Chicken Waste
Authors: Ryan John J. , Pilon Jean C. , Mc Leod Harry A. , Crober Donald C. , Sefton Arnold E.
Published: July 2010

Broiler chickens of both sexes were fed a diet with and without 125 µg/g of the coccidiostat clopidol (3,5‐dichloro‐2,6‐dimethyl‐4‐pyridinol). The waste from these animals was fermentated with a wood base and fed to lambs for a 5‐mo period. The clopidol in the lamb feed, the edible tissues, and faeces was measured at slaughter by gas chromatography (GC) with electron capture (EC) detection and confirmed by mass spectrometry (MS). Lamb silage from chicken waste contained 70 to 80 µg/g clopidol. Kidney levels of treated groups averaged between 0.4 to 0.75 µg/g, while those in liver were 0.2 to 0.4 µg/g. Muscle and fat tissue contained 0.1 µg/g and lower concentrations. Corresponding values for blood and faeces were 0.1 to 0.5 and 0.2 to 0.8 µg/g. An additional 10 to 30% more clopidol was present in the kidney, liver, and blood but not the faeces in the form of the glucuronide conjugate. Clopidol was passed on from the chickens to the lambs by feeding of chicken waste but did not appear to accumulate in the lambs.
Studies of Phosphorus Movement Using Salt Marsh Microecosystems
Authors: Everest J. W. , Davis D. E.
Published: July 2010

Microecosystems of a salt marsh community were designed, constructed, and used to follow phosphorus flux through the physical and biological components of that community. The biological components in these microecosystems were smooth cordgrass (Spartina alterniflora Loisel), diatoms, mud fiddler crabs (Uca pugnax Smith), periwinkle snails (Littorina irrorata Say), and ribbed mussels (Geukensia demissa Dillwyn; formerly Modiolus demissus Dillwyn). The physical components were the marsh soil and the seawater. Phosphorus (332P) placed 17.5 cm below the soil surface was abundantly present in the smooth cordgrass leaves and on the soil surface 4 days later. No 32P was secreted by the leaves of smooth cordgrass during the experiment. The rapid transfer of phosphorus to the soil surface was found to be the result of the burrowing activity of the fiddler crabs.
Particle‐Size Analysis by Pipette and SediGraph
Authors: Welch Norman H. , Allen Paul B. , Galindo Donnie J.
Published: July 2010

The pipette and SediGraph methods of particle size analyses were compared on 55 samples. The best agreement between the two methods was on 12 of the 55 samples treated to remove organic matter and soluble salts. The correlation for all sizes combined from the 55 samples was 0.97 with a standard deviation from regression of 5.54%. The agreement between the two methods was good at all individual sizes except the % < 50 µm where the correlation was 0.12.

Neither method is well suited to particle size analysis of suspended sediment samples with low concentrations or limited quantities of sediment. The major differences between the two methods are the time and labor required to perform the actual analysis and to calculate the analytical results.
Phosphorus Loading from Urban Stormwater Runoff as a Factor in Lake Eutrophication: I. Theoretical Considerations and Qualitative Aspects
Authors: Browman M. G. , Harris R. F. , Ryden J. C. , Syers J. K.
Published: July 2010

A theoretical fractionation of urban runoff phosphorus (P) according to its chemical mobility and potential biological impact is presented and the P fractions feasible for routine analysis established. Urban runoff P from two separate storm sewer systems draining residential areas in the Lake Wingra basin (Madison, Wis.) was characterized in detail. Flow‐weighted mean concentrations of dissolved inorganic P (Pi) for individual runoff events ranged from 0.10 to 2.11 mg P/liter and generally comprized ≥ 79% of the total dissolved P (Pt), allowing optimization of routine P characterization by the determination of dissolved Pi (or dissolved Pt) and total P. Flow‐weighted mean concentrations of total particulate P (Pt) ranged from 0.14 to 2.37 mg P/liter. However, while the composition of the particulate Pt at the lower concentrations was widely variable, at the higher concentrations particulate Pt was constituted mainly of organic P (Po). Flow‐weighted mean concentrations of dissolved Pi were more consistently correlated at a significant level with particulate Pt and particulate Po than with particulate Pi. The higher concentrations of dissolved and particulate P were associated with leaf and elm fruit fall, in the fall and spring, respectively, and with longer dry periods immediately before runoff events. A significant proportion (35 to 50%) of the particulate Pt occurring during the first flush and high flow phases of runoff events would remain suspended in the lake photic zone for several days. The upper limit for potentially available P in urban runoff can be given by dissolved Pi (or dissolved Pt) plus 0.25 × particulate Pt, for the watersheds studied.
Volatilization of Some Herbicide‐Related Nitrosamines from Soils
Authors: Oliver J. E.
Published: July 2010

The volatilization of four nitrosamines from soil was studied under laboratory conditions. From 30 to 80% of the low molecular weight nitrosamines that were surface‐applied volatilized within a few hours. Incorporation of nitrosamines into the soil reduced both the extent and rate of volatilization. Most of the nitrosamine volatilization occurred within the first few days; this behavior contrasted with that of two dinitroaniline herbicides, which continued to volatilize for several weeks.
Poliovirus Movement During High Rate Land Filtration of Sewage Water
Authors: Lance J. C. , Gerba C. P.
Published: July 2010

Research with soil columns that are good models of a field ground water recharge system showed that most polioviruses are held near the soil surface. Secondary sewage effluent seeded with poliovirus type 1 (LSc) was filtered through 250‐cm columns packed with calcareous sand from an area in the Salt River bed that is used for ground water recharging of secondary sewage effluent. When the concentration of poliovirus added to the sewage water was increased from 0.9 × 102 to 2.6 × 104 PFU/ml, the number of viruses detected at each soil depth increased with the increasing virus concentration in the sewage water. However, the percentage of added viruses that remained at each depth was about the same for each concentration. The differences in the strength of the negative charge among members of a given viral population could account for the adsorption of some viruses near the soil surface while others move farther through the profile.

Increasing the flow rate from 0.6 to 1.2 m/day caused a virus breakthrough of <1% of the added virus. However, 99% of the viruses still were removed from the infiltrating water at flow rates as high as 12 m/day. The velocity of water movement through the soil may be the single most important factor affecting the depth of virus penetration.
Trifluralin Movement in Runoff from a Small Agricultural Watershed
Authors: Rohde W. A. , Asmussen L. E. , Hauser E. W. , Wauchope R. D. , Allison H. D.
Published: July 2010

Little trifluralin (α,α,α‐trifluoro‐2,6.dinitro‐N,N‐dipropyl‐p‐toluidine) moved in the surface flow from a small agricultural watershed located in the Southeastern Coastal Plain. Movement of trifluralin in 1974 and 1975 in surface water was 0.17 and 0.03%, respectively, of the total amount applied (1.12 kg/ha). Trifluralin movement in the shallow subsurface flow (above the 214 cm depth) was recorded only in 1974 and was negligible. Trifluralin was detectable in the soil from the 1974 application before the 1975 application. Soil concentration of trifluralin in 1974 was 320 ng/g (immediately after application) in the 0‐ to 10‐cm depth and after 114 days the concentration decreased to 73 ng/g. However, no trifluralin was detected in the 30‐ to 60‐cm depth 60 days after application. Simulated surface runoff from subplots on the watershed produced measurable concentrations of trifluralin 38 days after application, but it could not be detected after 71 days. Trifluralin movement was greater in runoff caused by simulated rainfall than that from natural rainfall due to the high application rate of water (19.1 cm/hour) and the lack of a vegetational buffer. Trifluralin loss in the simulated rainfall runoff water from a small plot directed through a 24.4‐m waterway was reduced 96% under dry and 86% under wet conditions. Hence, trifluralin movement can be significantly reduced and possibly managed by buffer strips or vegetated waterways adjoining cropped areas. Appropriate use of these buffer areas should reduce to acceptable levels the chemical concentration in the runoff before the runoff reaches the surrounding streams.
Effects of Wood Products Harvest on Forest Soil and Water Relations
Authors: Patric James H.
Published: July 2010

The effects of silvicultural treatments on streamflow have been evaluated for 20 years on a 34.7‐ha forested catchment on the Fernow Experimental Forest, near Parsons, in north‐central West Virginia. Selection harvest of 13, 8, and 6% of the basal area in 1958, 1963, and 1968, respectively, had negligible effect on any measured property of water. In 1969–1970, 31.7 ha were harvested by clearcutting, leaving a 3.0‐ha protective strip of lightly cut forest extending about 20 m along both sides of the stream channel. This treatment had no effect on stormflow or stream temperature, but water yield increased 253 mm (38%) during the first year after cutting. Concentrations of sediment, nitrate, calcium, magnesium, potassium, and sodium in streamflow increased slightly. These effects on water quality were held to low levels by the protective strip and prudent management of logging roads. Subsequent cutting of the protective strip and clearing the stream channel in 1972 increased water yield 40 mm (9%) and raised stream temperature as much as 7.8°C. Luxuriant regrowth over the entire watershed reduced all effects on water within 2 years after each treatment, and no effect from any treatment was measurable after 1977.
Sorption of Ozone and Sulfur Dioxide by Petunia Leaves
Authors: Elkiey T. , Ormrod D. P.
Published: July 2010

Shoots of three cultivars of Petunia hybrida Vilm. of differing ozone (O3) and sulphur dioxide (SO2) sensitivity were exposed to O3 and SO2 in closed chambers for observation of pollutant absorption through the stomates and adsorption by leaf surfaces. The cultivar least sensitive to injury, ‘Capri’, absorbed the least ozone or SO2 but adsorbed the most. The sensitive ‘White Cascade’ had the opposite sorption pattern. Absorption of the individual gases was generally less from the mixture, whereas adsorption rates were similar whether the gases were supplied singly or in mixture. The existence of substantial differences in surface adsorption could introduce error in measurements of pollutant absorption by leaves.
Persistence of Fluridone in Small Ponds
Authors: Muir D. C. G. , Grift N. P. , Blouw A. P. , Lockhart W. L.
Published: July 2010

Fluridone {1‐methyl‐3‐phenyl‐5‐[3‐(trifluoromethyl)phenyl]‐4‐[1H]‐pyridinone} was applied to three small ponds (5 by 3.5 m2) to give water concentrations of 5,000, 700, and 70 µg/liter, respectively. Water, hydrosoil (0 to 3 and 3 to 6 cm depth), duckweed (Lemna minor), and minnows (Pimephales promelas) were collected for residue analysis over a 70‐week period following herbicide application. The half‐life of fluridone in the water column (0.5 m depth) ranged from 4 (at 700 µg/liter) to 7 days (70 µg/liter). Upon retreatment of one of the ponds the following year at 100 µg/liter, a half‐life of 4 days was observed. Fluridone persisted in hydrosoils with an apparent half‐life of 1 year or more at all treatment levels. Retreatment of one of the ponds resulted in a buildup of herbicide residue which dissipated more rapidly (half‐life of 20 weeks) than after the first treatment. Bioassays indicated that fluridone residues in hydrosoil from the ponds treated at 700 and 5,000 µg/liter, taken 42 to 70 weeks after treatment, were phytotoxic to duckweed. Fluridone levels in minnows were very low (< 0.02 to 0.14 µg/g) throughout the sampling period with bioconcentration factors ranging from 0 to 64. Fluridone levels in duckweed were proportional to the herbicide concentrations in the pond water with bioconcentration factors ranging from 19 to 85.
A Simulation Model for Sludge Decomposition in Soil
Authors: Gilmour J. T. , Gilmour C. M.
Published: July 2010

A computer simulation model which describes the rate of sludge decomposition in soil has been developed. The model, SLUDGE, uses first‐order kinetics. The rate constant was modified as the type of C species undergoing decomposition, temperature, and water content varied. The model computes decomposition on a daily basis during the rapid decomposition phase and on a monthly basis during the slow decomposition phase. Tests of the model showed that the model adequately describes sludge decomposition in soil. Model output for municipal sludge showed that half the sludge was decomposed over a 32‐ to 57‐month period for the soil temperature and moisture regimes considered. The time (month) of sludge addition had a large effect on the decomposition of the rapidly decomposable sludge fraction, but only a small effect on the half‐life of sludge. When yearly average soil temperature and water content data replaced monthly data in the model, predictions were changed in some cases suggesting use of yearly data could lead to erroneous results when computing sludge turnover. When “optimum” soil temperature and water content were used in the model, the half‐life of sludge was reduced by 37 to 66%; thus, laboratory studies conducted under “optimum” conditions would probably underestimate half‐lives under field conditions. In a modification of the model where annual June additions of sludge were made, the ratio of accumulated sludge to an annual addition was from 4.3 to 7.9 after 50 years of sludge addition. These ratios were slightly larger than those calculated using equations developed to compute such ratios for a relatively constant soil environment.
Ecological Characteristics of the Rhizosphere Microflora of Myriophyllum heterophyllum
Authors: Blotnick J. R. , Rho J. , Gunner H. B.
Published: July 2010

Bacterial populations associated with the rhizosphere and rhizoplane of Myriophyllum heterophyllum were studied in the littoral zone of a soft water, mesotrophic lake during the period of active growth of the plants. The composition of the rhizoplane community was found to differ distinctly from that of the adjacent sediments, while the population density of heterotrophic bacteria in each environment did not differ significantly. Higher populations of bacteria capable of nitrate reduction and ammonification did occur in the rhizoplane. Nitrogen‐fixing (acetylene‐reducing) activity was significantly higher on the root surface than in the sediment. The intensity of the rhizosphere effect was apparently related to the bimodal productivity cycle of Myriophyllum communities. Higher populations of bacteria involved in nutrient transformations in the rhizoplane suggest that these have a greater potential for supplying aquatic plants with readily available nutrients than do the nonrhizosphere populations.
Effect of Air‐filled Porosity, Nitrate Concentration, and Time on the Ratio of N2O/N2 Evolution During Denitrification
Authors: Letey J. , Valoras N. , Hadas Aviva , Focht D. D.
Published: July 2010

Nitrous oxide evolution from soils may contribute to partial destruction of the ozone layer in the stratosphere. Knowledge on factors affecting the N2O/N2 evolution ratio from soils is important in properly accessing the hazard associated with N2O evolution. Soils were wet to various air‐filled porosities with 400 ppm 15N‐labeled NaNO3 solution or to 5% air‐filled porosity with various nitrate concentrations. The treated soils were incubated in closed containers in the laboratory and periodically checked for N2O and N2 evolution. The incubation flasks were opened and brought to equilibrium with the atmosphere after each gas sampling. All samples which were sufficiently wet to cause denitrification had an initial high N2O evolution rate which decreased and approached zero with time. Dinitrogen gas evolution rate was initially low but increased after 3 to 4 days. The N2O/N2 ratio was initially high (infinity in some cases) and decreased rapidly with time. Except for the three lowest initial nitrate treatments, there was relatively high nitrate concentration throughout the incubation period; thus the decrease in the ratio could not be attributed to low nitrate concentration during the latter part of incubation. At a given time during the early stages of denitrification, the N2O/N2 evolution ratio increased with increased initial nitrate concentration. The ratio eventually became zero even under highest nitrate treatment. It is proposed that the enzyme dissimilatory nitrate reductase develops rapidly after anoxic conditions are initiated, and that the enzyme dissimilatory nitrous oxide reductase develops only after a period of time following anoxic conditions.
Plutonium in a Grassland Ecosystem at Rocky Flats
Authors: Little Craig A. , Whicker F. Ward , Winsor Terrol F.
Published: July 2010

Portions of the grassland around the Rocky Flats installation of the U.S. Department of Energy, located about 12 km northwest of the Denver metropolitan area, were contaminated with Pu between 1959 and 1964. This study was designed to elucidate the Pu distribution patterns in the terrestrial ecosystem immediately downwind of the contamination source. We concluded that wind erosion of contaminated soil was likely the chief mechanism of plutonium transport and that soil contained 99.7% of the plutonium in the system. Plant and small animal compartments combined contained less than 0.3% of the total Pu inventory which averaged about 53 µCi/m2 in the study area.
Soil as a Medium for Dairy Liquid Waste Disposal
Authors: Yang Shen‐Yi , Jones Joe H. , Olsen Farrel J. , Paterson John J.
Published: July 2010

A vegetative‐soil filter may be an inexpensive and effective means for the disposal of liquid dairy wastes. A field study was conducted at Southern Illinois University Dairy Center, Carbondale, Ill. during 1976–77 to evaluate the effectiveness of a vegetative‐soil filter for disposal of dairy effluent. The liquid waste was applied daily to tall fescue (Festuca arundinacea Schreb.) on a Hosmer silt loam (Typic Fragiudalf) with a 3% north‐facing slope. Applying effluent to the soil for absorption without runoff was found to eliminate the possibility of stream pollution except during rainfall and snowmelt runoff. The highest loading rate for this soil under the most adverse climatic conditions was 0.43 cm/day. The pollutants in the liquid waste were reduced significantly by flowing over the vegetative‐soil filter but not to acceptable levels. The BOD5, NH4‐N, suspended solids, and PO4‐P decreased by 41, 36, 69, and 16%, respectively. After 1 year of liquid waste application to the test site, perched ground‐water samples showed a 99% BOD5 decrease and a 90% removal of PO4‐P. A vegetative‐soil filter may be used for the disposal of liquid waste effluent from a dairy operation.
Decomposition of Sewage Sludge in Drying Beds and the Potential Role of the Earthworm, Eisenia foetida
Authors: Mitchell M. J. , Hornor S. G. , Abrams B. I.
Published: July 2010

Decomposition of sewage sludge in drying beds at Ley Creek (LC) and Meadowbrook‐Limestone (MB) Wastewater Treatment facilities in metropolitan Syracuse, N.Y. was monitored. LC and MB beds were derived from an anaerobically digested, primary sludge and an aerobically digested, activated sludge, respectively. Fluxes of O2, CH4, and CO2, as determined by in situ incubation of cylinders and analysis by gas chromatography, showed that at LC, aerobic and anaerobic, decomposition and photosynthesis occurred concomitantly due to high moisture. Similar analyses for two separate trials at MB found that both total decomposition rate and percentage of anaerobic decomposition (1 to 90%), as indexed by CH4 evolution vs. O2 consumption, decreased with time and were inversely related to sludge moisture content. O2 consumption rates, when standardized to 15°C, ranged from 10 to 80 µliter/g dry wt. For both LC and MB sludge, aerobic and anaerobic bacteria were abundant (3 × 107 to 6 × 108 colony‐forming units/g dry wt) and dominant bacteria were not enteric. Nematode densities ranged from 7 to 814 individuals/g dry wt.

A computer simulation model on the role of macroinvertebrates in decomposition was used for analyzing the effects of the earthworm, Eisenia foetida. This oligochaete was introduced into one‐half of the MB cylinders and was shown to accelerate decomposition and decrease the proportion of anaerobic decomposition if the sludge was below 375% moisture dry weight and 40% anaerobic decomposition. This stimulation was also reflected in increased nematode density and elevated Eh. Flooding of drying beds caused mortality to E. foetida.
Nitrous Oxide Evolution from Irrigated Land
Authors: Ryden J. C. , Lund L. J.
Published: July 2010

Nitrous oxide (N2O) fluxes from irrigated land cropped to vegetables in a coastal valley in California ranged from 0.0038 to 1.06 kg N/ha per day. For all sites, maximum fluxes (0.24 to 1.06 kg N/ha per day) were observed during the first post‐fertilization irrigation and were followed by a trend to lower values (0.048 to 0.144 kg N/ha per day) towards the end of cropping despite total fertilizer N inputs of 176 to 528 kg N/ha. The N2O flux showed a pronounced dependence on irrigation events with maximum fluxes associated with soil‐moisture contents between 18 and 22% and soil‐water suctions between 75 and 150 mbars. The magnitude of N2O flux during periods of high moisture content appeared to depend primarily upon soil nitrate concentration which declined during the cropping cycle. Data for N2O flux, soil moisture content, air‐filled porosity, and soil‐water suction suggested that denitrification rather than nitrification was the major process involved in N2O production at each field site. Mean N2O fluxes for each site coupled with soil‐water suction data for a 12‐month period suggested annual emissions of N2O ranging from 19.6 to 41.8 kg N/ha.
Mercury Accumulation in Fish and Invertebrates of the North Fork Holston River, Virginia and Tennessee
Authors: Hildebrand Stephen G. , Strand Rodney H. , Huckabee John W.
Published: July 2010

We investigated both total and methylmercury accumulation in fish and invertebrates in the North Fork of the Holston River below a currently inactive chloralkali plant (i) to quantify the extent of contamination, (ii) to determine what proportion of the variance in mercury concentration in fish can be explained by mercury concentration in water, sediment, benthic invertebrates, and (iii) to determine what proportion of mercury concentration in benthic invertebrates can be explained by mercury concentration in water and sediment. Fish species [rock bass (Ambloplites rupestris) and hog sucker (Hypentelium nigricans)] and benthic invertebrates were collected from stations above and below the plant, and axial muscle (fish) or whole animal (invertebrates) was analyzed for total mercury by flameless atomic absorption and for methylmercury by gas chromatography. The relation of total mercury concentration to fish weight and factors affecting mercury concentration in fish and invertebrates were examined through regression analysis.

Total mercury concentration in fish and benthic invertebrates decreased with distance below the plant. Significant linear regressions of total mercury concentration on fish weight were observed for some, but not all, samples examined. Mercury in the methyl form comprised 91.7% of total mercury in fish analyzed, while approximately 50% of the mercury in invertebrates was methylmercury.

Multiple regression analysis indicated 96.4% of the variance in total mercury concentration in rock bass and 80.5% in hog suckers was accounted for by mercury in water, sediment, and benthic invertebrates. Independent variables accounted for 97.4% of the variance in total mercury concentration in benthic invertebrates. The potential implication of these results for environmental monitoring programs is discussed.
Fractionation of Inorganic Phosphates in Calcareous Sediments
Authors: Hieltjes Arnold H. M. , Lijklema Lambertus
Published: July 2010

The selectivity of current fractionation schemes for inorganic phosphates in sediments has been tested on pure compounds. Results indicate that effective removal of calcium carbonate through ammonium chloride extraction is necessary in order to achieve satisfactory discrimination between iron‐ or aluminum‐bound phosphates and calcium phosphates. A simple extraction procedure based on this information has been applied to the sediments of Lake Brielle.
Methane Production From Ozonated Pulp Mill Effluent
Authors: Bremmon Craig E. , Jurgensen Martin F. , Patton John T.
Published: July 2010

A study was made on the production of methane from desugared spent sulfite liquor (SSL) reacted with ozone. The ozonated SSL was fed continuously to three anaerobic fermenters for three months as the sole source of carbon and energy. The fermenters were inoculated with anaerobic bacteria obtained from sewage sludge and acclimated for 1 month in ozonated SSL prior to continuous fermentation. Chemical and biological parameters such as COD, BOD5, total sulfur content, redox potential, pH, fatty acid composition, and methane bacteria populations were monitored to determine changes in the SSL during fermentation.

Methane production from ozone‐treated SSL averaged 1.7 liters/liter or 17 ml of CH4 produced/gram of volatile solids fed. Fatty acids analysis of fermenter effluent indicated a net production of 58 mM/liter of acetate during ozonated SSL fermentation. This acetic acid production shows future potential for further fermentation by protein‐producing yeast. Although the rate of conversion of volatile solids to CH4 in this process was not competitive with domestic or agricultural waste digesters, this study did indicate the potential benefits of ozonating organic wastes for increased methane fermentation yields.
A Mathematical Model for Estimating Pesticide Losses in Runoff
Authors: Haith D. A.
Published: July 2010

A simple mathematical model has been proposed for the estimation of losses of dissolved and solid‐phase pesticide in cropland runoff. The model is designed for use in water quality and pesticide screening studies for which field pesticide runoff data are unavailable. Hence, the model is based on commonly used methods for runoff and soil loss predictions and does not require calibration. A comparison of model predictions with measured atrazine (2‐chloro‐4 (ethylamino)‐6‐(isopropylamino)‐s‐triazine) losses from two small Georgia watersheds has indicated that the model provides a reasonable means of estimating the approximate magnitudes of long‐term (3‐years for the two watersheds) total pesticide runoff losses. Although large errors were sometimes observed in estimates of losses from single runoff events, the observed variations in pesticide losses among events and the distribution of these losses into dissolved and solid‐phase components were reflected in model predictions.
Nitrate‐Nitrogen Leached Below the Root Zone During and Following Alfalfa
Authors: Robbins C. W. , Carter D. L.
Published: July 2010

The nitrate‐nitrogen (NO3‐N) contribution to subsurface drainage water by irrigated alfalfa (Medicago sativa L.) in crop rotations was evaluated by measuring the soil water flux and NO3‐N concentration below the root zone of alfalfa and crops following alfalfa with and without additional nitrogen fertilization. Under alfalfa grown on Portneuf silt loam (Durixerollic Calciorthid) with a permeable hardpan, 44 kg NO3‐N ha−1 year−1 moved below the root zone at concentrations between 3 and 15 ppm. During the growing season following alfalfa, 85–96 kg NO3‐N ha−1 year−1 moved below the root zone under nonfertilized bean (Phaseolus vulgaris) crops at concentrations between 1 and 83 ppm. The second growing season after alfalfa, 17–29 kg NO3‐N ha−1 year−1 at 3–15 ppm NO3‐N moved below the root zone of nonfertilized bean and wheat (Triticum aestivum L.) crops. A field planted to corn (Zea mays L.) and fertilized with 200 and 170 kg N ha−1 the first and second year after alfalfa lost 153 and 108 kg NO3‐N ha−1, respectively, from leaching. Leachate N concentrations varied from 1 to 64 ppm. Unfertilized corn lost 60 and 17 kg NO3‐N/ha the first and second year after alfalfa, respectively, at leachate concentrations of 1–31 ppm. The NO3‐N concentration in the soil solution below only slightly permeable hardpan areas was between 13 and 67 ppm, but only 10–23 kg ha−1 year−1 moved below the root zone because of the lower water flux through the hardpan. Comparing these results with previous data for the same area suggests that considerable denitrification and/or dilution takes place at the water table interface since 5.2 ppm NO3‐N was the highest concentration measured in the subsurface drainage water with an average of 3.2 ppm NO3‐N. The NO3‐N contributed by alfalfa in the crop rotation was estimated to equal just half of that accounted for in the subsurface drainage in a previous study on the same irrigated tract.
Areal, Vertical, and Temporal Differences in Ground Water Chemistry: I. Inorganic Constituents
Authors: Spalding Roy F. , Exner Mary E.
Published: July 2010

Definite areal, vertical, and temporal differences were observed in the ground water chemistry of a 62 km2 area in Nebraska's Platte Valley. A network of 53 wells was monitored 10 times between July 1975 and July 1976 for dissolved solids, Ca2+, Mg2+, Na+, K+, HCO3−, SO42−, Cl−, F−, NO3‐N, PO4‐P, SiO2, pH, and temperature.

Areal differences were most pronounced in the shallow ground water and reflected upgradient land use and soil type. Average total dissolved solids (TDS) and nitrate‐nitrogen (NO3‐N) concentrations ranged from 557 to 2,210 mg/liter and from 0.1 to 33 mg/liter, respectively, with the lowest concentrations occurring downgradient from near‐pristine areas and the highest concentrations occurring downgradient from cultivated and irrigated fields.

In ground water downgradient from cultivated and irrigated fields, most of the chemical parameters had pronounced decreases in concentration with depth. Stratification was more pronounced in the bottomland than in the terrace and in the latter reflects mixing of the ground water caused by intensive pumping of irrigation water during the last four decades. Magnesium and potassium had marked decreases with depth regardless of upgradient land use.

Marked cyclic fluctuations in NO3‐N and SO42− concentrations generally were observed in the bottomland ground water. Sulfate concentrations, which were significantly correlated with TDS, Ca2+, Mg2+ Na+, and Cl− (r ≥ +0.89), peaked in late winter and early spring.

Ground water in secondary aquifers confined within or beneath a layer of clayey silt had an average TDS concentration of 304 mg/liter and almost negligible amounts (≤ 0.1 mg/liter) of NO3‐N. Temporal fluctuations in chemical constituents from these aquifers were the smallest observed within the study area.
The Influence of Organic Wastes and Inorganic Nitrogen Sources on Soil Nitrogen, Yield, and Elemental Composition of Corn
Authors: Sims J. T. , Boswell F. C.
Published: July 2010

This experiment evaluated the effect of synthetic N fertilizers, organic wastes, and fortified organic wastes on soil mineral and total N, crop yield, and elemental composition. Treatments consisted of equivalent rates of N (224 kg/ha) as NH4NO3, urea, sewage sludge, sewage sludge fortified with urea, leather tankage (LT), and organiform (leather tankage chemically fortified with urea‐formaldehyde). Corn (Zea mays L., cv. ‘DeKalb XL‐394’) was used as an indicator crop and soil N measurements were conducted throughout the growing season.

Soil levels of NH4‐N, NO4‐N, and total N indicated that the organic waste materials provided adequate amounts of available N for crop growth. Fortified and nonfortified wastes resulted in similar amounts of mineral and total N in the soil, indicating that fortification could reduce application problems associated with high loading rates of organic wastes. Accumulations of mineral N at the end of the corngrowing season suggest that the loading rates used in this study may have been excessive. While this excess available N would be beneficial for subsequent crops, it could also provide a source of contamination for surface and ground waters.

Organic wastes consistently produced yields and plant tissue N levels equal to or greater than yields and N levels obtained with ammonium nitrate or urea. The treatments increased Zn in plant tissue and on plots receiving sewage sludge, and Mn and Cr accumulations in the tissue of plants grown on leather tankage treated plots. Except for the LT‐treated plots at the early growth stage, crop growth and yield were uninhibited.
The Enrichment of Soil Phosphorus in Runoff Sediments
Authors: Sharpley A. N.
Published: July 2010

The effect of varying soil physical and chemical properties, soil slope, rainfall intensity, and source on the enrichment of soil P in runoff was evaluated under simulated rainfall conditions. The enrichment of P in runoff increased with increased P additions. The P enrichment ratio (ER) of Bernow soil increased from 2.43 to 6.29 at P additions of 0 and 100 kg P/ha, respectively. As rainfall intensity and soil slope were increased, ER decreased correspondingly. A significant linear relationship between in (ER) and in (sediment discharge) was obtained for all treatments studied. Similar slopes were obtained for soils ranging in texture from a fine sandy loam (−0.233, Bernow soil) to a clay (−0.264 and −0.252 for Houston and Pullman soils, respectively) under similar experimental conditions. In addition, the slopes were not affected by soil P status as slopes of −0.233 and −0.276 at 0 and 100 kg P/ha additions, respectively, were obtained for Bernow soil. With an increase in energy of runoff and kinetic energy of rainfall, a significant increase in slope of the relationship between In (ER) and in (sediment discharge) was obtained. In contrast, a decrease in energy of rain as in the case of overland flow and increased soil cover, resulted in a significant decrease in slope. The data indicated that runoff and rainfall energy and soil P status have a greater effect on ER than soil physical properties. A general relationship between ER and sediment discharge covering all treatments studied predicted ER values very similar to those measured in field studies and those predicted by a general relationship derived from field studies.
Die‐off of Fecal Indicator Organisms Following Land Application of Poultry Manure
Authors: Crane S. R. , Westerman P. W. , Overcash M. R.
Published: July 2010

Land‐applied animal manure can be a major contributor of agricultural nonpoint source pollution. For surface‐applied manures the time period prior to the first runoff is of greatest concern, because most enteric species initially exhibit rapid die‐off rates. The objectives of this investigation were to follow the die‐off of indicator organisms after manure application to a bar? soil surface and to ascertain if die‐off could be accurately modeled by first‐order‐kinetics. Poultry manure was surface‐applied at approximately 36.5 and 164 metric tons/ha on Davidson clay loam and Norfolk sandy loam plots in a controlled environment chamber at a constant temperature (24.5°C). Soil samples were analyzed at intervals during a 30‐day period for fecal coliforms and fecal streptococci. Modeling die‐off of fecal coliform during the first 7 days gave good agreement with experimental data showing an average die‐off rate constant of 0.29/day. After 7 days, regrowth of fecal coliform populations was seen on all plots. Fecal streptococcal numbers declined steadily after the first 3 days of the 30‐day study and exhibited an average first‐order rate constant of 0.093/day. Neither soil type nor manure application rate seemed to influence the decline in organism populations. First‐order kinetics did not explain all aspects of die‐off, but it appears this model could be successfully employed as a first approximation for estimating bacterial kinetics in a larger nonpoint source pollution model for agricultural lands.