bluuebunny/crossref_metadata_2025 huggingface dataset:
Heavy Metals in Cottontail Rabbits on Mined Lands Treated with Sewage Sludge
Authors: Dressler R. L. , Storm G. L. , Tzilkowski W. M. , Sopper W. E.
Published: July 2010

Levels of heavy metals in soils, vegetation, and tissues of cottontail rabbits (Sylvilagus floridanus) on a Pennsylvania strip‐mined site treated with sewage sludge were compared with those from a non‐treated mine site to determine increases due to treatment effect. Concentrations of Cd, Cu, and Zn were higher in vegetation on the sludge‐treated site. Zinc was higher (P < 0.05) in femurs of cottontails from the treated site, but levels of most metals in the tissues of cottontail rabbits from the treated site were comparable to those from a non‐treated mine site and a nonmined area. Baseline values for the uptake of Cd were documented with captive cottontail rabbits fed diets supplemented with 0, 5, or 25 mg Cd kg−1. Captive rabbits fed diets supplemented with a Cd salt accumulated increasing levels of Cd in their tissues, except for muscle, as the dietary intake of Cd increased (P < 0.05). Liver and muscle tissue of rabbits collected on treated mine sites contained higher Cd levels than laboratory controls, but overall, cottontail rabbits did not accumulate metals on the sludge‐treated site at hazardous levels.
Influence of Sulfate, Nitrate, and Chloride in Simulated Acidic Rain on Radish Plants
Authors: Jacobson J. S. , Troiano J. J. , Heller L. I. , Osmeloski J.
Published: July 2010

The primary objective of this research was to test the hypothesis that sulfate (SO2−4), nitrate (NO−3), and chloride (Cl−), as major anionic components of rain, significantly affect plant growth or modify plant response to the acidity of rain. In the first experiment, above‐ground portions of greenhouse‐grown radish (Raphanus sativus L.) plants were given 10 1‐h exposures over a 3‐week period to simulated rain containing the individual acids, sulfuric (H2SO4), nitric (HNO3), hydrochloric (HCl), or a combination of H2SO4 and HNO3 at pH vlaues between 2.6 and 5.0. A second experiment was performed using 2‐h exposures on 4 consecutive days to simulated rain containing either H2SO4, HNO3, or HCl at pH values between 3.0 and 5.0. Reductions in hypocotyl growth but not shoot growth were obtained at pH 2.6 in the first experiment and at 3.0 and 3.4 in the second experiment. Both the linear and quadratic components of the dose‐response function for effects of acidity on hypocotyl dry mass were significant. There were no significant effects of anions on dry mass of hypocotyls nor was there a significant acidity by anion interaction in either exposure pattern. The similarity of effects on plant growth of H2SO4, HNO3, and HCl in simulated rain suggests that differences in concentrations and ratios of SO2−4, NO−3, and Cl− in rain may not be important for agricultural crops. The validity of these conclusions should be tested for other species and different environmental, edaphic, and treatment conditions.
Effect of Cadmium‐ and Zinc‐treated Sludge on Yield and Cadmium‐Zinc Uptake of Corn
Authors: Sikora F. J. , Wolt Jeff
Published: July 2010

Sludge obtained from a regional wastewater treatment plant in Tennessee was factorially treated with four levels each of Cd and Zn and applied to Statler sandy loam surface soil (Humic Hapludults) sown to corn (Zea mays L.) in a greenhouse experiment. The highest Cd and Zn additions (75.1 and 759 mg kg−1) soil, respectively, resulted in dry weight decreases of 19 and 25%, respectively, for corn tops and 47 and 56%, respectively, for corn roots. The 19% dry weight reduction at a Cd addition of 75.1 mg kg−1 soil was considerably less than values found in the literature. This comparatively modest dry weight reduction was attributed to a lower Cd availability due to Cd precipitation or binding in the sludge. Zinc effectively competed with Cd for uptake as evidenced by a decrease in Cd content of roots with increased Zn additions. On the contrary, Cd content of tops was not consistently decreased with increased Zn application. An increase in the Zn levels of sludge was also found to increase the solubility of Cd in the sludge and soil.
Uptake by Sagebrush of Uranium Progeny Injected In Situ
Authors: Simon Steven L. , Fraley Leslie
Published: July 2010

Uptake of 226Ra, 210Pb, and 210Po in mature big sagebrush (Artemisia tridentata) was studied in the environs of a U mine in Shirley Basin, WY. Radionuclide solutions were injected into the soil to elevate the soil activity while minimizing root disturbance and preventing soil surface contamination. The objectives of this study were to measure the concentration in leaves resulting from root uptake as a function of time and to determine the equilibrium concentration ratio (CR) for each radionuclide. The vegetation was sampled approximately every 90 d for a 2‐yr period. The maximum internal plant concentration of 226Ra, 210Pb, and 210Po was detected at the first sampling (81 d after soil injection for 226Ra, 28 d for 210Pb and 210Po). The concentration in leaves decreased over time following the first sampling to an apparent steady‐state value. The steady‐state CR values for 226Ra, 210Pb, and 2100Po, as determined in mature sagebrush, were approximately 0.04, 0.009, and 0.08, respectively, and were determined as the geometric mean (GM) of the CR data pooled over the 2nd‐yr period. The CR data were fit by nonlinear least squares to a exponential function that decreased with time to a constant value.
Aerobic and Anaerobic Degradation of Aldicarb in Asceptically Collected Soils
Authors: Ou L. ‐T. , Thomas J. E. , Edvardsson K. S. V. , Rao P. S. C. , Wheeler W. B.
Published: July 2010

Degradation and metabolism of [14C] aldicarb [2‐methyl‐2‐(methylthio)propionaldehyde O‐(methylcarbamoy) oxime] in soils under aerobic and strictly anaerobic conditions were investigated. Soils were collected aseptically from a 6‐ha tract in Dougherty Plains, GA. Under aerobic conditions, aldicarb (A) rapidly disappeared and aldicarb sulfoxide (ASO) was rapidly formed. The latter in turn was slowly oxidized to aldicarb sulfone (ASO2). Disappearance of A and formation of ASO and ASO2 were generally more rapid in surface soils and shallow subsurface soils than in deeper subsurface soils. A number of additional metabolites were detected, including thin layer chromatography (TLC)‐polar products, ASO oxime, ASO nitrile, and A acid. Half‐lives for total toxic residue (TTR) in 24 surface and subsurface soils ranged from 29 to 78 d, with an average of 52 d. Aldicarb sulfoxide was the principal metabolite in soils under strictly anaerobic conditions; ASO2, ASO oxime, and ASO acid in small quantities were detected in some soils; and TLC‐polar products were also detected in most soils. Half‐lives for TTR in three deep subsurface soils under strictly anaerobic conditions were shorter than in three shallow subsurface soils. Although A persisted considerably longer in anaerobic soils, anaerobic half‐lives for TTR in subsurface soils were significantly shorter than under aerobic conditions.
Nitrate Leaching Losses from Monolith Lysimeters as Influenced by Nitrapyrin
Authors: Owens L. B.
Published: July 2010

Three monolith lysimeters, each with a surface area of 8.1 m2 and a depth of 2.4 m, were planted to no‐till corn (Zea mays L.) for 6 consecutive years. The lysimeters contained a Rayne silt loam (Typic Hapludult), a well‐drained residual soil. Urea was placed in a slot approximately 10‐cm deep and 10 to 15 cm from the corn row at a rate of 336 kg N/ha. The urea applied to two of the lysimeters was treated with nitrapyrin [2‐chloro‐6‐(trichloromethyl)pyridine], a nitrification inhibitor, and applied untreated on the third lysimeter. Two years of unfertilized meadow immediately preceded the corn. Concentrations of NO−3; in the leachate from the lysimeters were higher during the corn years than during the meadow period. Concentrations showed seasonal variations during the last 3 yr of the study, but showed no increasing trend. The leachate from the lysimeters receiving the nitrapyrin treated urea had seasonally flow‐weighted NO−3; concentrations ranging from 6 to 40 mg/L, while the leachate from the lysimeter receiving untreated urea had seasonally flow‐weighted NO−3;‐N concentrations ranging from 20 to 54 mg/L. Nitrate‐N losses showed a similar treatment difference. The 6‐yr annual average NO−3; loss was 117 and 160 kg/ha from the lysimeters with the treated urea and untreated urea, respectively. This study demonstrates that nitrification inhibitors such as nitrapyrin, have a potential to reduce NO−3; leaching when applied with ammoniacal fertilizers.
Extent of Regeneration of the Microbial Community in Reclaimed Spent Oil Shale Land
Authors: Segal William , Mancinelli Rocco L.
Published: July 2010

Since the microbial community is an integral component of the soil ecosystem, an understanding of the microbiological parameters of reclaimed spent oil shale land is essential for environmental assessment of the potential for reclamation of such land. It was found that determination of the numbers of microorganisms, bacterial diversity and richness (number of genera), and biogeochemical activity indicated by relative rates of cellulose decomposition, yielded significant information regarding the regenerative potential of the microbial communities sampled from three shale mining areas in Colorado and Wyoming that had undergone varying degrees of weathering, leaching, fertilization, and revegetation. Compared to regional soils used as controls, the spent oil shale soils were characterized by low numbers of microorganisms, depressed values of bacterial diversity and richness, and low rates of cellulose decomposition. However, samples taken from 6‐yr revegetated sites were characterized by the least reduction in microbial numbers, higher indices of diversity and richness, and highest rates of cellulose decomposition, in comparison to intermediate values for the 3‐yr revegetated site, and the most extreme values for the nonrevegetated site. The latter site was characterized by very reduced numbers of bacteria, actinomycetes, and fungi, the lowest indices of richness and diversity indicative of a high level of environmental stress, and no decomposition of cellulose. It may be concluded that oil shale processing had a drastic negative impact on indigenous microbial communities in reclaimed, shale land. However, conditioning by weathering, fertilization, and revegetation does have a partially restorative effect on the microbial community; the degree of restoration progressively increasing with increasing length of time of these environmental conditions.
Water and Sediment Sampler for Plot and Field Studies
Authors: Dressing S. A. , Spooner J. , Kreglow J. M. , Beasley E. O. , Westerman P. W.
Published: July 2010

The design and performance characteristics of a flush‐type sampling device for plot and field studies are described. The sampler is weld‐constructed and requires excavation and water conveyance for installation. It operates with no external power supply and collects consistently a known fraction of water and sediment passing through it. In laboratory tests, the sampler collected 2.65% (number of data points [n] = 54, standard deviation [s] = 0.0040) of all water passing through it at average flow rates ranging from 18 to 196 L min−1. Sample volumes ranged from 0.75 to 18.7 L. Correlation analysis showed that sampling percentage was independent of flow rate (n = 40, correlation coefficient = r = −0.04) over the range tested, in other laboratory tests, 30 sampling runs with inflow rates and total sediment concentrations ranging from 35 to 182 L min−1 and 252 to 1410 mg L−1, respectively, showed that the ratios of waste to sample sediment concentrations were approximately one for total sediment (1.001), and for the sand (1.097), silt (1.008), and clay (1.020) fractions. Sand and clay ratios were shown to be statistically independent of total sediment concentration, but silt (r = 0.30, n = 30) and total sediment (r = 0.44, n = 30) ratios increased slightly with increasing total concentration. Monte Carlo simulation was performed to illustrate the suitability of the flush‐sampler for field and plot runoff studies. Simulation results indicated that for runoff estimates measurement error would exceed 10% with 33% probability for triplicate plots, but with only 16% probability in five plot studies. Additional simulation considering only measurement error associated with the sampler shows that the minimum number of paired samples required to detect sediment loss reductions of 50, 25, and 10% is 3, 4, and 16, respectively.
Corn and Wheat Response to Topsoil Thickness and Phosphorus on Reclaimed Land
Authors: Halvorson G. A. , Bauer A. , Schroeder S. A. , Melsted S. W.
Published: July 2010

Stripmining of coal drastically disturbs agricultural land and may alter many of the plant‐soil‐water relationships of undisturbed land. Plots were established on leveled moderately sodic clay loam mine spoil to evaluate topsoil thickness and P on crop production and soil moisture in a semiarid environment. A nonsodic sandy loam topsoil was replaced on the spoil at thicknesses of 0.05, 0.15, 0.30, and 0.60 m. Prior to topsoil placement, P was broadcast on the leveled spoil at rates of 0, 34, and 100 kg P ha−1. Phosphorus at rates of 0, 11, and 34 kg ha−1 was applied annually for 4 yr to plots seeded to hard red spring wheat (Triticum aestivum L.) using a drill attachment and by banding to corn (Zea mays L.). In the last 2 yr, P broadcast rates of 0, 12, and 12 kg P ha−1 on wheat and 0, 18, and 18 kg P ha−1 on corn were substituted for the drilled and banded P treatments. Corn silage and wheat grain yields in most years were significantly higher on 0.15‐, 0.30‐, and 0.60‐m topsoil compared to 0.05 m. The clay loam spoil was not as drought prone as the sandy loam topsoil and therefore, as the thickness of topsoil increased, the ability of the profile to continuously supply water to the growing crop decreased. The relationship between wheat yield and total water use was similar to undisturbed soils in the Northern Great Plains. Responses of wheat and corn to the one time broadcast application of P to the topsoil‐spoil interface or annual applications were generally small and occurred at the low rate of P.
Selenate and Selenite Mobility in Overburden by Saturated Flow
Authors: Ahlrichs J. S. , Hossner L. R.
Published: July 2010

The elution and sorption characteristics of selenate and selenite were measured in column studies. A composite of sandy loam textured strip‐mine overburden was adjusted to pH 2, 3, 5, 7, and 9 and packed into glass columns. Selenium was added to the surface as the Na salt of selenate (SeO2−4) or selenite (SeO2−3). Individual columns were leached with 1.5, 10, or 50 pore volumes of 0.01 M CaCl2. Selenate was mobile at all pH values and was completely leached from columns with <3 pore volumes of solution. Selenite was rapidly sorbed at all pH values. Very slight selenite movement was observed when high pH overburden was leached with 50 pore volumes of solution. The least movement was recorded when pH values were <7.
Residual Effects of Sewage Sludge on Soybean: II. Accumulation of Soil and Symbiotically Fixed Nitrogen
Authors: Heckman J. R. , Angle J. S. , Chaney R. L.
Published: July 2010

Nitrogen and heavy metals derived from sewage sludge may potentially affect N2 fixation and soybean [Glycine max (L.) Merr.] growth. Field studies were conducted at two locations in 1983 and 1984 to examine the residual effects of sewage sludge on N2 fixation in soybean. The Fairland plots (Typic Hapludults) were amended with two rates of anaerobically digested sludge in 1975. The Beltsville plots (Typic Paleudults) were established in 1976 with limed‐anaerobically digested, limed‐raw, limed‐compost, or heat‐treated sludge, and in 1978 with Nu‐Earth (Chicago, IL) anaerobically digested sludge. Nonnodulating and nodulating isolines of ‘Clark’ soybean were grown on the sludge‐treated plots, which consisted of various sludge rates and pH regimes. Dry matter and total N accumulation were determined in the shoots at the R4 stage of maturity. Dry matter and N accumulation by nonnodulating soybean generally increased due to greater availability of soil N on the sludge plots. In nodulating soybean, dry matter production and N2 fixation were enhanced by most sludges with the greatest increase occurring under moisture stress. In 1983, a dry year, dry matter of nodulating soybean and N2 fixation (estimated by the difference method) were increased by all sludges at Beltsville. During this year, dry matter and amount of N fixed increased from 16.5 g plant−1 and 285 mg N plant−1 (control) to 31.1 g plant−1 and 706 mg N plant−1 at the 672 Mg ha−1 limed‐compost sludge rate, respectively. In 1984, a normal rainfall year, dry matter and N2 fixation was moderately higher on sludge plots compared to control levels. Dry matter and N2 fixation showed a quadratic response due to overliming by high applications of limed‐digested and limed‐raw sludges. Evidence for toxicity of sludge metals on N2 fixation was not found at Beltsville sludge plots. However, a toxic effect may be suggested by high metal sludge at Fairland sludge plots. In addition to a decrease in the amount of N2 fixed, nonnodulating plant dry matter increased with sludge, whereas nodulating plant dry matter decreased. Results suggest that while sludge amended soil may enhance soybean growth, such beneficial results may be limited to sludges low in heavy metals.
Ammonium Bicarbonate‐DTPA and DTPA Extractions of Sludge‐amended Soils
Authors: Barbarick K. A. , Workman S. M.
Published: July 2010

A DTPA (diethylenetriaminepentaacetic acid) solution is typically used to extract sludge‐amended soils to determine the relationship between soil concentration and plant levels of certain trace elements. The objective of this study was to compare the standard DTPA soil test method with the ammonium bicarbonate (NH4HCO3)‐DTPA (AB‐DTPA) procedure for extraction of trace elements, and to correlate extractable levels with elemental concentration in leaf of Swiss chard (Beta vulgaris L., cv. Fordhook Giant) grown in the greenhouse and in the grain and straw of hard red winter wheat (Triticum aestivum L. cv. Vona) grown in the field. For the greenhouse study, sewage sludges containing low (Fort Collins, CO) and high (Chicago, IL) metal conent were added to Nunn clay loam (Aridic Argiustolls, pH = 8.0) and Redfeather loamy sand (Lithic Cryoboralfs, pH = 5.3) at rates ranging from 0 to 120 Mg dry sludge ha−1 in 15 Mg ha−1 increments. For the greenhouse study, coefficients of correlation (r) for the greenhouse study between AB‐DTPA and plant concentrations of Cd, Cu, Ni, and Zn in Swiss chard were > 0.90 for the calcareous soil (Nunn) and > 0.93 (except for Cu) for the acidic soil (Redfeather). Even though DTPA extracted less Cd, Cu, Ni, Pb, and Zn than AB‐DTPA, the r values between these two extractants were > 0.98 for each metal. For the field studies involving addition of a low metal sludge from Littleton/Englewood, CO, to four sets of plots from 1982 to 1985, only the DTPA levels of Zn correlated significantly (r = 0.84) with the associated grain concentration. In contrast, AB‐DTPA provided significant correlations between soil levels and concentrations of Cd (r = 0.57) and P (r = 0.43) in straw and the Ni (r = 0.42), Pb (r = 0.83), Zn (r = 0.82), and P (r = 0.39) in the grain. The field studies indicate that when a low metal sludge is applied at rates consistent with N needs of the crop, levels of AB‐DTPA extractable Zn and possibly Pb should indicate the potential for Zn and Pb uptake into wheat. Because the concentrations of Cd, Cu, and Ni in the sludge applied did not result in plant uptake at levels that were significantly different from those in the untreated control, nonsignificant correlations were found. Also, AB‐DTPA extraction of soils showed that adequate P was present so that no response to the P added with the sludge was expected. For the field study, the r values between AB‐DTPA and DTPA were > 0.95 for each metal. The results indicate that AB‐DTPA is as valid as, if not superior to, DTPA for metal extraction and offers the additional advantage in allowing nutrient analysis if one wants to assess both plant nutrients and trace metals.
Transport of Solids in Streamflow from Coastal Plain Watersheds
Authors: Sheridan J. M. , Hubbard R. K.
Published: July 2010

Concentrations and loads of solids transported in runoff from seven southeastern Coastal Plain watersheds with low‐gradient drainage systems were related to hydrologic patterns. Total solids (TS) concentrations in streamflow averaged 96 ± 81 mg L−1. Concentrations were significantly lower during the December through May high runoff period. Higher TS concentrations (> 250 mg L−1) primarily occurred following prolonged no‐flow periods, which typically occur in the late summer and fall. Monthly TS loads (avg, 26.7 kg ha−1) were largely a function of monthly runoff volume. Suspended sediment (SS) concentrations in streamflow averaged 15 ± 20 mg L−1. Suspended sediment concentrations were significantly higher from March through August, when agricultural activity was greatest. Monthly SS loads (avg, 4.60 kg ha−1) were also largely a function of monthly runoff volume. The dissolved component is the predominant portion of TS transported in runoff from Coastal Plain watersheds. The low sediment loads are attributed to deposition occurring within the low‐gradient, heavily vegetated drainage systems.
Mobility of Sludge‐borne 3,3′‐Dichlorobenzidine in Soil Columns
Authors: Chung Duck Young , Boyd Stephen A.
Published: July 2010

Fate of the carcinogen 3,3′‐dichlorobenzidine (DCB) in sludge‐amended soil was evaluated. Carbon‐14‐1abeled DCB was used as a tracer to examine mineralization and mobility of DCB present in sludge. Dichlorobenzidine was shown to be very persistent in soil and sludge‐amended soil with < 2% of the added [14C]DCB evolved as 14CO2 during a 182‐d incubation. Mobility of DCB was evaluated by using soil columns (5 by 45 cm) that were irrigated with 2.54 cm water d−1 for 84 d. The total 14C recovered in leachate water was from 0.16 to 0.063% of the total 14C added to the top 15 cm of the soil column at time zero. The strong binding of DCB to soil constituents rendered it highly immobile despite being placed in a sandy soil that was irrigated with large amounts of water. However, some finite, albeit small, quantity was apparently leached through the soil profile at a relatively constant rate. The immobilization of DCB presumably results from tbe formation of humus bound DCB residues and from its low water solubility.
Soybean Growth and Boron Distribution in a Sandy Soil Amended with Scrubber Sludge
Authors: Ransome L. S. , Dowdy R. H.
Published: July 2010

A field study was conducted to determine the feasibility of using scrubber sludge residues from coal‐fired generation of electricity as an agricultural soil amendment. Boron distribution between plant, soil, and soil water was monitored to determine whether scrubber sludge application would enhance crop growth by alleviation of the B‐deficient status of an irrigated Hubbard loamy sand (Udorthentic Haploborolls) without elevation of soil or soil‐water B to phytotoxic levels. Soybean (Glycine max L.) plants were grown on plots amended with 0, 10, 20, and 40 Mg scrubber sludge ha−1. Effects on plant populations, bean yield and nutrient content, B availability, soil‐water B concentration, and electrical conductivity (EC) were measured for three growing seasons. Hot‐water extractable soil B was elevated from low (0.40 mg kg−1) to sufficiency levels (> 1.0 mg kg−1) by application of at least 20 Mg scrubber sludge ha−1; such levels were maintained for two to three growing seasons. Soil‐water EC and B concentrations reached levels potentially detrimental to soybean production during the application year at the 40 Mg ha−1 rate. Elevated soil‐water EC and B levels were mediated after the first growing season as leaching removed excess soluble components from the root zone. Soybean populations decreased linearly with increasing rates of application the first two growing seasons following application. Yield was significantly reduced the first year but was enhanced in response to scrubber sludge application the third growing season. Leaf B content was significantly increased all 3 yr; symptoms of B toxicity were visible only during the year of application. Seed B, although significantly affected by treatment, did not parallel leaf B or yield.
Transfer of Toxic Trace Substances by Way of Food Animals: Selected Examples
Authors: Hansen Larry G. , Lambert Richard J.
Published: July 2010

Toxic substances enter the food chain by various routes. Extrapolation of potential adverse effects from basic toxicity studies is difficult, but practical considerations also limit the utility of food chain studies. Hexachlorobenzene (HCB) appears to be more readily absorbed by cats (Felis catus) from contaminated pork than as a pure compound, but it is difficult to generate a frankly toxic product by feeding pigs (Sus scrofa domesticus) HCB. Polychlorimated biphenyls (PCB's) should not accumulate readily in soil‐plant‐animal chains, but PCB congeners exhibit a wide range of bioavailability and toxicity, cautioning against excessive extrapolation. Cadmium levels in food chains are greatly influenced by agronomical practices. Cadmium bound to metallothionein (MTN) is less bioavailable in short‐term feeding studies, although it is reportedly more acutely toxic than CdCl2 to some species. Long‐term feeding of liver and kidney from high‐Cd sewage‐sludge‐exposed sows, however, had no adverse effect on male or female rats (Rattus norvegicus). Male rats first accumulated organic Cd at a greater rate, but CdCl2 ultimately produced higher kidney residues after 6 to 8 weeks. The CdCl2 was more toxic to rat duodenal muscosa than was Cd‐MTN purified from swine liver. These studies tend to support the concept of food‐chain attenuation as well as enhancement of trace substance toxicity.
Changes in Forest Floor and Water Quality Following Thinning and Clearcutting of 20‐Year‐Old Pine
Authors: McClurkin D. C. , Duffy P. D. , Nelson N. S.
Published: July 2010

Effects of timber cutting on forest floor, sediment movement, and chemical quality of percolating water and of plot runoff are reported for pole‐size loblolly pine (Pinus taeda L.) plantations on fragile soils of the upper Coastal Plain. Treatments were clearcut, thin, and nocut. Water quality measurements were derived for runoff samples from 0.002‐ha plots and for percolating water from zero‐tension lysimeters at a 15‐cm depth. Forest floor on clearcut plots was reduced to near the minimum regarded as necessary for site protection within two years. Regardless of cutting treatment, more N and P were coming into the plots via precipitation than were leaving via plot runoff and percolation combined. More K appeared to be leaving the sites than was coming in via rainfall, regardless of cutting treatment. Sediment concentrations in plot runoff tended to be proportional to cutting intensity. Nutrient content in percolation waters was unrelated to cutting intensity. Nutrient concentrations in plot runoff were high compared to concentrations reported in stormflows from local, small catchments with similar characteristics, but plot runoff was <3% of annual rainfall.
Minespoil Acidity and Rowcrop Productivity
Authors: Dancer W. S. , Jansen I. J.
Published: July 2010

The development of extremely to strongly acid (pH 3.5–5.5) minespoil at a surface coal mine in Illinois resulted in unusually low field corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] grain yields, particularly in years of severe drought stress. Spoil acidity, measured in terms of pH, was evaluated as a factor contributing to or interacting with drought stress. Drought stress was most clearly expressed in corn by increasing numbers of barren plants. Very strongly acid spoil confounded drought stress and resulted in barren plants, even in wet years. In 1980, the driest year, variation in spoil pH accounted for 58% of the variation in both barrenness and corn grain yield without topsoil replacement. Where 20 cm of topsoil had been replaced, variation in spoil pH immediately underlying the topsoil accounted for 40 and 34% of the barrenness and grain yield, respectively, in 1980. Soybean grain yield correlated most strongly (r = 0.969) with spoil pH in a year of adequate precipitation, suggesting a different physiological response than that for corn. Depressed soybean grain yield occurred, and plants were characterized by potentially phytotoxic leaf concentrations of Al (>70 mg/kg) and Mn (>300 mg/kg), where the pH was less than 5.5. Results indicate that newly reclaimed minespoils having a pH ≤4.5 are unacceptable for row crop production in Illinois. Spoils having a pH between 4.5 and 5.5 should also be avoided or limed.
Response of Cotton, Alfalfa, and Cantaloupe to Foliar‐deposited Salt in an Arid Environment
Authors: Hofmann W. C. , Karpiscak M. M. , Bartels P. G.
Published: July 2010

The cooling towers at the Palo Verde Nuclear Generating Station (PVNGS), located 80 km west of Phoenix, AZ, will release an estimated 2.1 Mg/d of particulates (primarily salts) into the atmosphere when the station is in full operation. The saline drift will disperse and settle onto agricultural fields surrounding the station. Field studies were conducted in 1953 to investigate the influence of foliar‐applied saline aerosol on crop growth, foliar injury, and tissue elemental concentration on cotton (Gossypium hirsutum L.), alfalfa (Medicago sativa L.), and cantaloupe (Cucumis melo L.) in an arid environment. The treatment aerosol solutions simulated treated wastewater effluent and included all essential plant nutrients and other elements, including trace concentrations of heavy metals. The treatments included unsprayed plots, and plots sprayed with salt solutions at 0 (distilled water), 8, 83, and 415 kg/(ha yr). The alfalfa received an additional 829 kg/(ha yr) treatment. The species were evaluated in separate experiments on Mohave clay loam and Sonoita sandy loam soils (Typic Haplargid) near Marana, AZ. Cotton treated with 415 kg/(ha yr) had significantly less chlorosis and tended to be slightly taller than the cotton in the unsprayed plots. The alfalfa treated at a rate of 829 kg/(ha yr) showed significantly more leaf margin necrosis than did the unsprayed alfalfa. In the cantaloupe, there were no visually apparent differences among salt treatments. Hand‐harvested cotton plots had a significant reduction in seed cotton yield at the 415 kg/(ha yr) treatment (P ≤0.05). A similar though nonsignificant, trend towards reduced yield with increased salt treatment was observed in machine‐harvested cotton plots. No significant yield differences were detected in the alfalfa or cantaloupe.
Effects of Emissions from a Coal‐fired Power Plant on Soybean Production
Authors: Jones Herbert C. , Noggle J. C. , McDuffie Charlie
Published: July 2010

An air pollution exclusion system was designed, tested, and operated at four field sites during four growing seasons near the Tennessee Valley Authority Widows Creek Steam Plant to measure the effect of emissions from the coal‐fired power plant on soybean [Glycine max (L.) Merr., cv. Essex] production. Soybean plants were exposed to background levels of ambient air pollutants. When the plume from the power plant was at ground level the air pollution exclusion system was activated and passed charcoal‐filtered air through the plant canopy of the control plots, thereby reducing SO2 concentration to 10 to 20% of ambient level. The maximum 3‐h average SO2 concentration ranged from 1935 to 9944 µg/m3 (from 1972–1975) and from 502 to 1478 µg/m3 (from 1977–1979). Soybean plants were also grown in charcoal‐filtered and unfiltered air in greenhouse chambers for 4 yr (1972–1975) near the Widows Creek Steam Plant and for 3 yr (1977–1979) at a remote site 70 km from the power plant. Soybean yield was significantly reduced by 27% in greenhouse chambers with unfiltered air compared with chambers with charcoal‐filtered air near the power plant. Emissions from the power plant significantly reduced soybean yield by 12% for only 1 out of 4 yr in the field tests. An estimated 6.4% of the total leaf area in the ambient air + SO2 plots showed chlorosis after an exposure to a maximum 1‐h average SO2 concentration of 1663 µg/m3. At the remote location, soybean yield averaged 25% less in unfiltered air than in filtered air, indicating that air pollutants other than power plant emissions were affecting soybean yield at both sites.
Lead and Molybdenum in Soils and Forage near an Atmospheric Source
Authors: Schalscha E. B. , Morales M. , Pratt P. F.
Published: July 2010

Soil samples collected in 1982 and 1983 from locations near an industrial park consisting of a Mo ore processing plant and a car battery manufacturing industry were analyzed for total and extractable Mo and Pb. Grass samples collected from the same locations were analyzed for total Mo and Pb and three samples were analyzed for total Cu. The objectives were to assess the potential toxicity of Mo and Pb to horses (Equus caballus) and cattle (Bos taurus) and to verify earlier research done in the same general area. Total and extractable Mo and Pb in soils and total Mo and Pb in grasses decreased with increase in distance downwind from the industrial site. The car battery plant ceased operation soon after the 1982 sampling and the extractable Pb in 1983 was much lower than in 1982, indicating a rapid reaction of Pb with soils. The total and extractable Mo in soils were about the same in 1983 as in 1982 even though the Mo industry installed electrostatic precipitators in late 1982 with a claimed 90% reduction of Mo emissions. The Pb, Mo, and Cu contents of grass samples indicated no potential problems of Pb toxicity to livestock, but the Mo concentrations and Cu/Mo ratios showed that cattle in the area would suffer from Mo‐induced Cu deficiency (hypocuprosis).
Transpiration Effect on the Uptake and Distribution of Bromacil, Nitrobenzene, and Phenol in Soybean Plants
Authors: McFarlane J. Craig , Pfleeger Thomas , Fletcher John
Published: July 2010

The influence of transpiration rate on the uptake and translocation of two industrial waste compounds, phenol and nitrobenzene, and one pesticide, 5‐bromo‐3‐sec‐butyl‐6‐methyluracil (bromacil), was examined. Carbon‐14 moieties of each compound were provided separately in hydroponic solution to mature soybean plants [Glycine max (L.) Merr. dwarf cultivar Fiskeby v] maintained under three humidity conditions. The uptake of each compound was determined by monitoring the removal of 14C from the hydroponic solution. The extent to which 14C was adsorbed to roots and translocated to plant shoots and leaves was examined by assaying root and shoot parts for 14C. Bromacil was taken up slower than the other chemicals, had the most 14C translocated to the shoot, and the amount translocated to the shoot responded directly to the rate of transpiration. In contrast, both phenol and nitrobenzene were rapidly lost from solution and bound to the roots. Less than 1.5% of the 14C from phenol or nitrobenzene was translocated to the plant shoots. Increased transpiration rates had little influence on root binding of 14C; however, increasing transpiration rate from low to medium was associated with an increased uptake of nitrobenzene. The three chemicals studied have similar Log Kow values, but their interactions with soybean were not the same. Thus, despite the usefulness of the octanol/water partitioning coefficient in predicting the fate of organic chemicals in animals and in correlating with root binding and plant uptake for many pesticides, log Kow may not be equally useful in describing uptake and binding of nonpesticide chemicals in plants.
Release of Aluminum following Whole‐Tree Harvesting at the Hubbard Brook Experimental Forest, New Hampshire
Authors: Lawrence G. B. , Fuller R. D. , Driscoll C. T.
Published: July 2010

From fall, 1983, through spring, 1984, an experimental watershed at the Hubbard Brook Experimental Forest in New Hampshire was commercially whole‐tree harvested. Stream chemistry was monitored along an elevational gradient for approximately 1 yr prior to and 2 yr following the treatment in both the experimental watershed and an adjacent reference watershed. Whole‐tree harvesting initially resulted in a large increase in stream NO−3 and basic cation (Ca2+, Mg2+, Na+, and K+) concentrations and a decrease in stream sulfate concentrations. A decrease in pH and increase in Al concentrations followed. Elevational trends in stream chemistry were qualitatively similar before and after the cut, although the absolute concentrations of solutes changed markedly. These responses are explained by increased soil nitrification coupled with decreased vegetative uptake following the whole‐tree harvest. Acidity generated by nitrification facilitated the mobilization of basic cations and increased anion adsorption. When NO−3 production exceeded the release of basic cations, stream pH declined and Al concentrations increased. Aluminum was released in an entirely inorganic form resulting in potentially toxic concentrations in streamwater.
Soil Properties, Irrigation Water Quality, and Soil Moisture Level Influences on the Movement of Nickel in Sewage Sludge‐Treated Soils
Authors: Welch J. E. , Lund L. J.
Published: July 2010

A column study was conducted to assess the effects of soil properties, irrigation water quality, and soil moisture level on the movement of Ni in sewage sludge‐treated soils. Surface layer samples of six soil series were packed into 24 columns, 10.2 cm in diameter and 110 cm in length. An air‐dried, anaerobically digested sewage slude was mixed into the top 15 cm of soil at a rate of 300 Mg ha−1. The columns were maintained at moisture levels of saturation and unsaturation (16.7 kPa tension) and leached with two waters of different quality. The unsaturated columns were irrigated about every 12 d with 5.08 cm of water for 13 months. The saturated columns were leached for 7 months. At the termination of the experiment the columns were cut open and the soil sectioned into 3‐cm intervals the entire length of each column. Samples were extracted with water and 4 M HNO3 and analyzed for chemical constituents. Irrigation water quality did not affect the amount of Ni leached from the sludge‐amended soil layer nor the depth of Ni movement. Mass balance calculations showed that an average of 3.3% of sludge‐applied Ni leached from the sludge‐amended soil layer of the saturated columns compared to 10.7% for the unsaturated columns. An average of 96.7% of sludge‐applied Ni remained in the sludge‐amended soil layer of the saturated columns compared to 89.3% for the unsaturated columns. For the saturated columns an average of 74.9% of sludge‐applied Ni leached from the sludge‐amended soil layer was accumulated in the 0‐ to 3‐cm soil interval compared to 46.5% for the unsaturated columns. Nickel movement below the sludge‐amended soil layer for the saturated columns ranged from 3 to 15 cm with an average of 9 cm compared to a range of 3 to 45 cm and an average of 18 cm for the unsaturated columns. Correlation and regression analysis indicated that pH and soil texture were the soil properties that best predicted the depth of Ni movement.
Phytoavailability of Boron from Organic Sources
Authors: Burkman W. G. , Adriano D. C. , Afre J. L.
Published: July 2010

Experiments were conducted to determine the use of certain organoborates as potential sources of B for plant nutrition and to assess the sensitivity to them by different crop species. Of particular interest was sodium tetraphenylboron (NaTPB), a specific precipitant for radiocesium. For comparison, the inorganic source of B, boric acid (BA), was used as the control source of B. Greenhouse experiments indicated the following: (i) BA and NaTPB produced similar toxicity symptoms in the various crops studied; (ii) the order of sensitivity to NaTPB for various species followed the usual order for B toxicity, i.e., members of the bean (Phaseolus spp.) family are most sensitive, whereas cereals and chard (Beta vulgaris L.) were least sensitive; (iii) crop dry matter yields can best be predicted by the applied soil B on a coarse‐textured soil than by the plant B concentration; and (iv) at the same B level added to soil, NaTPB was more deleterious to plant growth than BA. A germination study indicated that at equal levels of B in substrate solution, the organo‐borates, NaTPB, and diphenylboric acid were more injurious than BA to root and shoot growths, providing more conclusive evidence that the organic constituents of these compounds are also phytotoxic.
Effects of Simulated Acid Rain on Yield Response of Two Soybean Cultivars
Authors: Porter P. M. , Banwart W. L. , Hassett J. J. , Finke R. L.
Published: July 2010

An important component of the effects of acid rain on our ecosystem is its impact on the yield of agricultural crops. Field experiments were conducted for 3 yr to determine the effects of simulated acid rain on seed yield of two soybean [Glycine max (L.) Merr.] cultivars, ‘Amsoy 71’ and ‘Williams 82’. Soybeans were grown on a Flanagan silt loam (fine, montmorillonitic, mesic Aquic Argiudoll) and protected from ambient rainfall by movable rain exlusion shelters. Plants were treated biweekly with simulated rain of pH 5.6, 4.6, 4.2, 3.8, 3.4, and 3.0. For Amsoy 71 there was a linear decrease in yield with increasing rainfall acidity for 1 of 3 yr but no significant effects for the other two. Thus acid rain appears to reduce the yield of some soybean cultivars slightly but this effect is not consistent from year to year. Amsoy 71 and Williams 82 soybean treated with the most acidic rain, pH 3.0, resulted in average yields for the 3 yr of the study of approximately 3 and 4% lower than the average yields for the other treatments, respectively. However, calculations from the response functions developed have shown that at current levels of rainfall acidities the effects on yield are very small. With an increase in rainfall acidity of 50% in Illinois the predicted yield decrease for Amsoy 71 and Williams 82 soybean would be less than 1%. Similarly the expected increase in yield of these cultivars would be 1% or less if acidity in the rainfall were reduced by 50%. While there may be beneficial effects of reduced S and N oxide emissions, these results suggest the resultant lower rainfall acidities are not likely to produce noticeable changes in yield of soybean.
Deposition of Air‐borne Acidifiers in the Western Environment
Authors: Young J. R. , Ellis E. C. , Hidy G. M.
Published: July 2010

Regional deposition chemistry in the western USA is reviewed and analyzed to assess the potential for acid deposition effects in the rural West. Annual average and seasonal data from NADP/NTN sites over the period 1978 to 1984 are analyzed. These data meet specific data completeness criteria to ensure a representative wet deposition data set. Acidity levels in western precipitation are typically less than one‐fifth of their values in the East. The conventional method used to calculate annual average pH values does not account for net alkalinity present in some samples. This method overestimates acidity in the West by as much as 58% on an annual basis. Concentrations and depositions of SO2−4 and NO−3 are generally one‐tenth to one‐half of eastern values. Sulfate deposition is well below that associated with adverse effects on the environment. Sulfate concentrations are highly correlated with Ca2+ concentrations and only weakly correlated with H+ concentrations; in the East the converse is true. This result suggests the importance of suspended soil dust as a mediating factor in precipitation acidity. Dry and wet deposition in the mountainous terrain containing potentially susceptible ecosystems is estimated to be roughly equal in magnitude. Deposition from interception of cloud or fog droplets is estimated to contribute significantly to total deposition only in mountains along the Pacific Coast. Regional source‐receptor relationships in the West are poorly defined due to inadequate meteorological and deposition data. Areas in which our understanding of the acid deposition phenomenon in the West is inadequate are described. Specific objectives for acid deposition research in the West are identified and prioritized.
Bacterial Pollution in Runoff from Agricultural Lands
Authors: Baxter‐Potter Wanada R. , Gilliland Martha W.
Published: July 2010

A review of the literature reporting the methods and results of studies concerned with the nature of nonpoint source microbial pollution leads to several conclusions: (i) Comparison of data from different studies may be complicated by variation in the choice of indicator organisms, variation in watershed size and homogeneity, and variation in media and procedures for determining fecal streptococcus densities. (ii) The ratio of fecal coliform to fecal streptococcus densities can be used to help identify particular sources of fecal pollution, but its usefulness declines with age. Its usefulness may also be affected by media and procedures used to determine fecal streptococcus densities, particularly when data derived from different media or procedures are compared. (iii) Bacterial densities in runoff from agricultural lands often exceed water quality standards. This is true of virtually all types of agricultural land. (iv) Although some connection between bacterial densities and stream discharge during storm events is apparent, the relationship is not simple. Factors such as temperature, hydrologic proximity of pollution sources, livestock management practices, wildlife activity, fecal deposit age, and channel and bank storage, all affect bacterial densities in runoff. Of these factors, only the influence of fecal deposit age on bacterial releases has been studied and quantified. (v) There is in the literature no loading function to predict bacterial densities in runoff that satisfactorily considers the factors listed above; however, typical density values may be used in a simple loading function to estimate probable density ranges.