bluuebunny/crossref_metadata_2025_split huggingface dataset:
Selenium Uptake by Some Agricultural Crops from Central California Soils
Authors: Wan H. F. , Mikkelsen R. L. , Page A. L. 
Published: July 2010

AbstractGreenhouse experiments were conducted to study Se uptake and partitioning by crops grown in five California soils of differing physical and chemical properties. Alfalfa (Medicago sativa L.), barley (Hordeum vulgare L.), beet (Beta vulgaris L.), and tomato (Lycopersicon esculentum Mill.) were grown in soil to which 0, 0.5, and 1.5 mg Se(VI) kg−1 was added. Alfalfa was also grown in four additional soils to which 0, 0.5, 1.5, and 3.0 mg Se(VI) kg−1 had been added. Plants were grown to maturity, separated into plant parts, and analyzed for yield and tissue Se. For the barley, beet, and tomato, the edible portion of the plant contained much less total Se than the generally inedible plant parts. The presence of soluble SO2−4 in the soil was the major soil factor in determining Se accumulation by plants. Alfalfa grown in low‐SO2−4 soil accumulated Se to a concentration 10 to 20 times greater (> 1000 mg Se kg−1) than plants growing in high‐SO2−4 soil (< 100 mg Se kg−1). When exposed to Se(VI) in the root zone, all plants tested were capable of accumulating Se to concentrations potentially harmful to animals.
Sulfate Mobility in an Acid Danish Forest Soil
Authors: von Freiesleben Niels Erik 
Published: July 2010

ABSTRACTA key question in the acidification of soils due to atmospheric deposition of strong acids is the accumulation of SO2−4 in the soil. Sulfate leaching was studied in the laboratory in undisturbed soil cores taken in a Typic Udipsamment under spruce forest. The soil cores were watered with natural throughfall water (pH 3.6) or with throughfall acidified to pH 3.3 or 2.8 with a mixture of sulfuric and nitric acid (1:1, molar basis). A total of 660 mm of throughfall was applied during 11 months. The technique of using soil cores produced increased nitrification and mineralization in the soil, causing a continuous acid production in the soil cores and decrease in the leachate pH during the experiments. Soil solution concentrations of SO2−4 were in the range 0.4 to 1.5 mmol L−1, total Al 0.2 to 1.5 mmol L−1, and pH 3.5 to 4.1. Stability diagrams using Al and SO2−4 activities and pH indicate that precipitation of a solid phase with the composition of AlOHSO4 may control the Al and sulfate activities in the soil solutions in the Bw horizon but not in the Ap horizon. The equilibrium constant for this basic Al sulfate was estimated at 20°C, pKs = 17.36 and at 5°C, pKS = 17.05. The 35S labeled SO2−4 was added once to the same soil cores followed by 15 mm throughfall per day (Natural or adjusted to pH 2.8). After application of 75, 150, or 225 mm of throughfall water the distribution of 35S‐SO2−4 in the soil cores was determined. From 38 to 100% of the applied 35S‐SO2−4 was retained in the soil cores and of this amount 32 to 63% was found in the top of the Bw horizon, which was highest in free Al and Fe oxides. The studied soil did not accumulate SO2−4 under ambient field conditions. In the laboratory, however, SO2−4 accumulation was demonstrated when the soil was exposed to increased SO2−4 load and temperature as well as decreased pH, showing that SO2−4 sorption/desorption may buffer variations in SO2−4 concentrations in soil solutions, and thereby delay effects of acidification on cation leaching.
Alternative Ozone Dose Metrics to Characterize Ozone Impact on Crop Yield Loss
Authors: Rawlings J. O. , Lesser V. M. , Heagle A. S. , Heck W. W. 
Published: July 2010

AbstractPrevious studies of the National Crop Loss Assessment Network (NCLAN) relating the impact of ozone (O3) on agricultural crops have used the seasonal arithmetic average of O3 for either a 7‐ or 12‐h daily period as the measure of dose in the dose response relationships. This study investigated the use of alternative dose metics that gave differential weighting to hourly O3 concentrations according to level of O3, period of day, or total hourly solar radiation. Data were used from two NCLAN studies in which two different methods of O3 addition were used for 7 h/d. In addition, one study included 12 h/d exposure for one method of O3 addition. The residual sums of squares from fitting a common Weibull response model to each experiment were compared over the range of dose metrics. The results suggested that the dose metrics using equal weighting of peaks and valleys closely reflected plant reaction to O3, but the fit of the dose‐response models improved if relatively little weight was given to the final 5‐h component (1700–2200 h EDT) of the 12‐h exposure period. Weighting by total hourly solar radiation gave results very similar to the best obtained from differential peak‐valley weighting and 7 h:5 h weighting.
Transformations of Nitrogen‐15‐Labeled Fertilizer Nitrogen and Carbon Mineralization in Incubated Coal Mine Spoils and Disturbed Soil
Authors: Reeder J. D. 
Published: July 2010

AbstractLimited information is available concerning N transformations in exposed geologic materials of disturbed lands in the western USA. A laboratory incubation study was therefore conducted using 15N to trace the dynamics of fertilizer 15NH+4 added to samples of one topsoil and five coal mine spoils from Colorado and Wyoming. Carbon dioxide evolution, N mineralization, nitrification, microbial immobilization, and NH+4 fixation within clay minerals were monitored over time. The organic matter in three of the spoils was considerably less susceptible to microbial decomposition than the topsoil organic matter, whereas the organic matter in the fourth spoil was slightly less susceptible than, and in the fifth spoil comparable to, topsoil organic matter in susceptibility to microbial decomposition. However, the amount of plant‐available N mineralized was at least five times higher in the topsoil than in any of the spoil materials. The data suggest that, under field conditions, none of the spoil materials evaluated in this study will likely be able to adequately supply the N requirements of a reseeded plant community. The significantly more active microbial population of the topsoil immobilized more of the added 15NH+4 than in any of the spoils except the shale, whereas more of the added 15NH+4 was nitrified and remained as NO−3 in the spoils than in the topsoil. The data indicate that under field conditions, a larger proportion of added fertilizer NH+4 will be susceptible to loss via NO−3 leaching or volatilization in the spoils than in the topsoil.
Chemical and Decomposition Characteristics of Anaerobic Digester Effluents Applied to Soil
Authors: Sweeney D. W. , Graetz D. A. 
Published: July 2010

AbstractA study was conducted to determine the elemental concentrations of an effluent that resulted from the anaerobic digestion of rum distillery by‐products (also called molasses residue) and decomposition characteristics in soil as measured by CO2 evolution. For comparison, two additional effluents from the anaerobic digestion of swine wastes and bovine wastes were included (Susscrofa and Bos taurus, respectively). The carbon content of oven‐dry molasses residue and swine waste effluents were both approximately 250 g kg−1, whereas the bovine waste was 152 g kg−1. The molasses residue effluent sample had a greater K concentration on an oven‐dry basis than the swine or bovine waste materials. However, the concentrations of most other elements were higher in the swine waste effluent. In contrast, higher solute concentrations were found for most elements in the molasses residue effluent than in the swine waste effluent. An analysis of variance performed on total CO2‐C evolved after 20 d as well as at the end of the experiment (117 d) indicated an interaction between effluent source and rate. This was caused by the low amount of CO2 evolved from soil amended with the bovine waste effluent regardless of application rate. At day 20, cumulative CO2 evolution was higher with the molasses residue effluent than with the swine waste effluent; however, by day 117, only at the high application rate was CO2 evolution higher with the molasses residue. Lower application rates allow for proportionally more short‐term decomposition of the molasses residue and swine waste effluents than at higher rates. Although effluent sources result in different amounts of total evolution, between 40 and 50% of the total CO2 evolved may occur in the first 20 d.
The Fate of Nitrogen from Injected Liquid Manure in a Silt Loam Soil
Authors: Comfort S. D. , Kelling K. A. , Keeney D. R. , Converse J. C. 
Published: July 2010

AbstractA field experiment was conducted on a Piano silt loam (Typic Argiudoll) in southcentral Wisconsin to monitor N transformations following liquid manure injections. Liquid manure with and without a nitrification inhibitor [nitrapyrin, 2‐chloro‐6‐(trichloromethyl)pyridine, 13 mg a.i. L−1 liquid manure] was injected into an uncropped area in June 1985. Soil samples were taken using a grid placed over the vertical cross‐section of the injected bands permitting spatial sampling in the vertical plane. Sampling was done 5, 12, 26, 39, 67, 99, and 350 d after manure application by progressive exposure of the band. Soil water content, pH, NH4‐N, (NO2 + NO3)‐N, Cl, and water‐soluble C were determined. The synagraphic computer program, SYMAP, was used to evaluate spatial changes in inorganic N concentrations in the manure injection zone. Nitrapyrin was not effective in inhibiting nitrification at the rate used. Nitrification occurred at the outer fringes of the band within 5 d; maximum concentrations of 300 to 800 mg NO3‐N kg−1 occurred throughout the injection zone at 26 d. High respiratory activity in the injection zone was indicated by an almost threefold decrease in water‐soluble C between day 5 (750 mg C kg−1) and day 12 (270 mg C kg−1). Water content remained higher than the surrounding soil in the injection zone for 99 d. Once NO3 leaching occurred, NO3‐N/Cl ratios decreased with depth under the injection zone. The abundant supply of NO3 and readily oxidizable C, combined with the high moisture environment, led to the conclusion that liquid manure injections created an environment conducive for denitrification.
Sensitivity of Plants to Acidic Fog
Authors: Musselman R. C. , Sterrett J. L. 
Published: July 2010

AbstractSeveral crop species were exposed to simulated acidic fog from pH 1.6 to 3.2 or to 5.6 in greenhouse experiments. Foliar injury and growth of radish (Raphanus sativus L. cv. Cherry Belle), tomato (Lycopersicon esculentum Mill. cv. Tiny Tim), onion (Allium cepa L. cv. Southport White Globe), spinach (Spinacia oleracea L. cv. Bloomsdale Long Standing), bean (Phaseolus vulgaris L. cvs. Pinto and Improved Kentucky Wonder), alfalfa (Medicago sativa L. cvs. Mesa Sirsa and Moapa 69), sweet orange (Citrus sinensis L. cv. Valencia), and trifoliate orange (Poncirus trifoliate L.) were determined after exposure to simulated fog at acidites down to pH 1.6. Potted plants were exposed for 2 h after sunset on 2 consecutive days every week for 4 (radish) or 12 (others) weeks. Acidic fog at ambient pH levels injured plants, but large amounts of acidic input were required for injury to occur. Although crop species varied in magnitude of response to acidic fog, in general, pH 3 or below was required to induce foliar injury and pH 2 or below was required to induce foliar injury and pH 2 or below to reduce growth. Radish, spinach, alfalfa, and Valencia orange were sensitive to foliar necrosis from acidic fog, while onion was tolerant. Acidic fog reduced yields of dry bean and spinach, reduced root weight of tomato, and delayed maturity of bean and alfalfa.
Effects of Sludge Application Sequence on Carbon and Nitrogen Mineralization in Soil
Authors: Wiseman John T. , Zibilske L. M. 
Published: July 2010

AbstractA laboratory experiment was conducted to determine the effects of an initial sludge amendment on C and, primarily, N mineralization of a second sludge amendment. In this study, a municipal sludge containing Cr‐tanning effluent, and a domestic sludge with little metal contamination were added to a sandy loam soil at rates of 6.65 g domestic sludge kg−1 soil and 9.75 g municipal sludge kg−1 soil. Sludges were reapplied 40 d later at the same rates in all sequence combinations. Respiration and nitrification were increased in sludge‐amended soil. At least 70% of the total C mineralized from both sludges was evolved within the first 11 d. Initial sludge application had little effect on C evolution from subsequent applications. Nitrogen mineralized from sludge‐amended soils during the initial 40 d of incubation was linearly related to time. A second application of sludge did not change the linear nature of N mineralization in all but one treatment. Ammonium N rapidly decreased and was negligible 2 weeks after sludge addition. Nitrite nitrogen levels were negligible throughout the experiment. By the end of the incubation period, the quantity of nitrate produced in all sequences of sludge addition was similar. Results indicate little effect of initial sludge addition on C and N mineralization of a second sludge amendment, even if the initial sludge applied contained a high concentration of Cr.
Impact of Ozone on the Growth and Yield of Trees: A Review
Authors: Pye John M. 
Published: July 2010

AbstractData from 25 experiments on seedlings of 43 tree species and hybrids show that ozone (O3) can reduce growth and photosynthesis at concentrations common in many areas of the USA. Seedlings have been primarily employed for such studies for logistic reasons, and will likely provide the greatest breadth of information for some time to come. However, a number of impediments limit application of seedling response studies to assessment of impacts on regional timber production. Large trees differ from seedlings in a number of ways, including C allocation and canopy structure, and methods must be developed to account for these differences if information from seedling studies is to prove useful to forest impact assessment. Understanding how competition mediates individual tree responses will require investigation of whether systematic differences of microclimate leaf morphology that exist across canopies affects foliage sensitivity to O3, and whether the maximum growth rates of genotypes are correlated with susceptibility to O3. Definitive information on these factors is necessary to assess impacts of O3 on stand development and diameter distributions in both multi‐ and single species stands. Of critical economic importance is whether O3 preferentially damages taller, more valuable individuals within stands and more valuable, faster growing stand types.
Septic System Performance on a Coastal Barrier Island
Authors: Cogger C. G. , Hajjar L. M. , Moe C. L. , Sobsey M. D. 
Published: July 2010

AbstractA field experiment was conducted on a Corolla fine sand (Aquic Quartzipsamment) to evaluate wastewater treatment by septic systems under conditions typical of Atlantic coastal barrier islands. The effects of loading rate and water table depth on wastewater treatment were studied. Two absorption fields were installed and were designated the upper and lower fields based on their relative topographic locations. The trenches in the lower field were 30 cm closer to the water table than the trenches in the upper field. Each field consisted of nine absorption trenches. Three loading rates (1, 4, and 16 cm d−1) were each replicated three times in a completely randomized design. Groundwater samples around the trenches were collected biweekly from shallow wells (1.5–1.9 m deep) between May 1982 and December 1983, and were analyzed for NO−3‐N, NH+4‐N, soluble P, Na+, Cl−, K+, and fecal coliform bacteria. During the first year the water table was within 30 cm of the lower field trenches 20% of the time, and anaerobic conditions prevailed. Groundwater samples collected adjacent to the trenches contained predominantly NH+4‐N, fecal coliform counts averaged over 25 000 MPN (most probable number) L−1, and the redox potential averaged <300 mV. During the second autumn the lower field showed aerobic tendencies due to drier weather and a deeper water table. The upper field remained aerobic throughout, with almost complete nitrification occurring. Average fecal coliform counts were reduced to 60 MPN L−1, and the mean redox potential was >500 mV. The wastewater loading rate had a significant effect on the levels of all constituents, but the loading rate effect was smaller than the water table effect. Phosphorus movement appeared to be related to pore‐water velocity.
Sorption and Degradation of Aldicarb and its Oxidation Products in a Soil‐water Flow System as a Function of pH and Temperature
Authors: Lemley A. T. , Wagenet R. J. , Zhong W. Z. 
Published: July 2010

AbstractThe sorption and degradation of aldicarb [2‐methyl‐2‐(methylthio) propionaldehyde O‐(methylcarbamoyl)oxime], aldicarb sulfoxide [2‐methyl‐2‐(methylsulfinyl)propionaldehyde O‐(methylcarbamoyl)oxime], and aldicarb sulfone [2‐methyl‐2‐(methylsulfonyl)propionaldehyde O‐(methylcarbamoyl) oxime] in a sandy loam soil were determined under varying pH and temperature conditions. The experiments were performed using a soil‐column methodology, which allows a steady state water flow and nonsteady state addition of pesticide. The edition curve (concentration vs. time) was interpreted using analytical solutions to the convection‐dispersion equation that included linear sorption and pseudo‐first‐order degradation. The sorption of the three species changes slightly with pH over the range studied (pH 5–8).The degradation varies with pH, but not in the same manner as found in aqueous solution studies. Sorption decreases as the temperature is increased from 15 to 35°C. Degradation is also temperature dependent in this range and for aldicarb sulfone can be represented by a linear Arrhenius plot from which activation energies can be derived. There is good agreement between the calculated activation energy for aldicarb sulfone and that obtained in aqueous solution studies. The results of this study have provided information about the thermodynamics of the aldicarb system and have demonstrated the usefulness of the soil‐column flow method as a good laboratory model for chemical transport and transformation in soil.
Nitrogen Mineralization Kinetics in Soil During Long‐term Aerobic Laboratory Incubations: A Case Study
Authors: Bonde Torben A. , Lindberg Torbjorn 
Published: July 2010

AbstractLiterature data describing curves of cumulative net N mineralization characterized by an initial lag‐phase and obtained by long‐term (26 weeks) aerobic laboratory incubations were fitted to different regression models by means of nonlinear regression analysis. The model offering the most appropriate description of the data were selected on the basis of the residual sum of squares left unexplained by the regression. The models employed and compared to the classical first‐order model were a mixed‐order, one‐component model: urn:x-wiley:00472425:equation:jeq2jeq198800472425001700030011x-math-0001 a mixed/first‐order, two‐component model: urn:x-wiley:00472425:equation:jeq2jeq198800472425001700030011x-math-0002 and a simplified special case of the previous, mixed/linear, two‐component model: urn:x-wiley:00472425:equation:jeq2jeq198800472425001700030011x-math-0003 where Nm and N0 are the amount of mineralizable N present in the soil at time t and time 0; Na and Nr are the amounts of mineralizable N initially present in the available and resistant fractions, respectively; ti equals length of incubation; rate constants h1 and h2 belong to the mixed‐order model; k is a first‐order rate constant; and C denotes the slope of the linear tail following the pattern described by the mixed‐order expression. Data from three soils, unamended or amended with manure, were best described by the mixed/first‐order or, alternatively, the mixed/linear model. The fit was significantly better than that offered by the classical first‐order, one‐component model. The prediction of potentially mineralizable nitrogen (N0) varied between 108 and 240 mg N kg−1 soil in an unamended soil, depending on the choice of model
Hydrogen Ion Concentration and Alkalinity of Reservoir Water in the Sierra Nevada, California, and Correlations with Air Pollutants
Authors: McColl J. G. 
Published: July 2010

AbstractPardee reservoir supplies water for the east San Francisco Bay Area from a large forested drainage basin located in the Sierra Nevada foothills, extending east to the crest of the mountain range. Analyses of weekly data of reservoir discharge water indicate that [H+] has been increasing (1954–1985 data) and alkalinity decreasing (1944–1985 data). Hydrogen ion concentration and alkalinity of reservoir water are correlated with NOx (and SO2 to a lesser extent) emissions from the San Francisco Bay Area. Emissions of NOx are about four times greater than those of SO2. A lag‐time of 3 to 4 yr improves the correlations, especially those of SO2. Greatest increases in [H+] occur in spring when the snowpack is melting. In the 1950s, spring melt had a dilution effect on [H+], but now [H+] increases during spring melt. The following is an explanation for the seasonal variations observed: Atmospheric NOx and SO2 appear to have their greatest effect on [H+] of water when there is little contact of runoff with soils and rocks. There is no correlation between acidity and alkalinity during the winter when water penetrates the soil profile, resulting in proton exchange with soil “base cations.” During summer, when runoff is minimal, other processes within the reservoir appear to control [H+] and alkalinity. Alternative hypotheses are discussed, which may help explain the observed trends in [H+] and alkalinity over seasons and years. These hypotheses largely involve processes within the reservoir, but without historical data their importance remains unclear.
Agricultural Impacts of Coal Mine Subsidence: Evaluation of Three Assay Methods
Authors: Darmody R. G. , Steiner J. S. , Jansen I. J. , Carmer S. G. 
Published: July 2010

AbstractA microcomputer and spread sheet program were used to store and analyze data from a collection of maps and aerial photographs in a research project concerning the agricultural impacts of underground coal mine‐induced subsidence. Topographic, soils, and mine maps along with pre‐mine archival photos and 1:12 000 aerial photos flown over the 3 yr of the project were used. The research area included about 18 000 ha of predominantly agricultural land. The overall objective of the research project was to assess the damage to agricultural production caused by underground coal mine subsidence. The work reported here details the development and evaluation of the method used to meet the overall objective. A 64‐point grid overlay adjusted to fit a township section on each of the images was used to mark individual sampling points. The categories of information recorded at each grid point were: mine name, township, section, grid point, land use, subsidence impact, mine type, mine panel orientation to slope, soil type, and soil slope. Each category had several classes to give a total of 196 possible classes for each of 3 yr of the study. These classes were visualiy assigned under each grid point on an image and then recorded on a 640 Kbyte microcomputer spread sheet. It was then possible to calculate each class area and class combination interactions over the time of the study. The validity of the approach was confirmed by two independent checks and by corn (Zea mays L.) yields determined at selected sites. The method is inexpensive and applicable to other similar land use or environmental studies.