bluuebunny/crossref_metadata_2025_split huggingface dataset:
Agriculture and Water Quality in the Canadian Great Lakes Basin: II. Fluvial Sediments
Authors: Wall G. J. , Dickinson W. T. , van Vliet L. J. P. 
Published: July 2010

AbstractUnit‐area yields of suspended sediments discharged from 11 small (<6,000 ha) agricultural watersheds in southern Ontario ranged from <100 to 1,000 kg ha−1 year−1 in a 2‐year study. Estimated bank erosion contributed between 0 and 30% of the suspended sediment, while estimated cropland sheet and rill erosion contributed 70–100%. Regression analyses relating 14 watershed characteristics to unit‐area yields showed that percent clay of the surface soil and percent row crop were the most significant (R2 = 0.64) factors in estimating suspended sediment yields.Detailed studies in the agricultural watersheds were used to generate and test three independent methods for the prediction of suspended sediment yields from cropland. The agricultural contribution to suspended sediment were predicted for the Grand and Saugeen river basins and for the over 300 subbasins of the Canadian Great Lakes Basin. It was estimated that agricultural land‐use activities contribute over 650 × 103 t of suspended sediment to the Great Lakes annually.
An Evaluation of Three Pesticide Runoff Loading Models
Authors: Lorber Matthew N. , Mulkey Lee A. 
Published: July 2010

AbstractThree nonpoint source runoff models were tested and compared for their abilities to predict the movement of the pesticides toxaphene and atrazine (2‐chloro‐4‐(ethylamino)‐6‐(isopropylamino)‐1,3,5‐triazine) from a 15.6‐ha watershed in the Mississippi Delta region and a smaller watershed in the Southern Piedmont. The three models are the Agricultural Runoff Management (ARM), Continuous Pesticide Simulation (CPS), and the Chemical, Runoff, and Erosion from Agricultural Management Systems (CREAMS). Published data on runoff, erosion, toxaphene, and atrazine runoff were used to test the models. Testing exercises indicated that all models accurately reproduced field data. For the total period of study, model predictions of total runoff differed from field observations by 15% or less. For the CPS and ARM models, predictions of total erosion differed from observations by 6%, whereas CREAMS underpredicted erosion by 25%. All models are within 10% of observations in overland toxaphene loss predictions. Five‐year simulations indicated that the models can differ in their predictions of peak events. Sensitivity analysis indicated that ARM can predict higher losses of soluble chemicals than CPS or CREAMS, due to an interflow component unique to the ARM model. Similarly, estimation of a sediment enrichment in the CREAMS model resulted in higher toxaphene loss predictions than the other two models.
Nitrogen and Phosphorus Movement in Compost‐Amended Soils
Authors: Inman J. C. , Mc Intosh M. S. , Foss J. E. , Wolf D. C. 
Published: July 2010

AbstractThe application of high rates of sewage sludge can pollute ground water if significant levels of nutrients move through the soil. A field study was conducted to investigate the effect of composted sewage sludge on NO3‐N, PO4‐P, and electrical conductivity (EC) levels in soil water collected at three depths. Composted municipal sewage sludge was disked into a Chester silt loam (Typic Hapludult) at rates of 0, 150 and 300 dry t/ha. White pine (Pinus strobus L.) seedlings and hybrid poplar (Populus generosa Henri) cuttings were grown on the plots, which had been seeded with ‘Kentucky 31’ tall fescue (Festuca arundinacea Schreb.). For 30 months, beginning the spring after compost application, NO3‐N, PO4‐P, and EC of the soil‐water solution were monitored in subsurface water samples taken from the Ap, B, and C horizons, which corresponded to depths of 15, 45, and 100 cm, respectively.During the year following the compost application, concentrations of NO3‐N were highest, 70–80 µg NO3‐N/mL, in the C horizon in the 300‐t/ha treatment. However, the corresponding concentrations decreased to <10 µg NO3‐N/mL by 30 months after compost addition. Total Kjeldahl N (TKN) concentrations of the soils treated with 150 and 300 t/ha of compost were approximately two and three times higher than those in control soils, respectively. The TKN concentrations in compost‐treated soils showed <7% decrease over the 30 months. The PO4‐P concentrations of water samples in compost‐treated soils were generally below 0.08 µg PO4‐P/mL, and never exceeded those concentrations found in control soils. The EC of water samples increased with the compost additions. After 267 d, EC values averaged 1.0 mmhos/cm in the 300‐t/ha treatment, and 0.7 mmhos/cm in the 150‐t/ha treatment, as compared with 0.2 mmhos/cm in the control. The EC values of the sludge compost treatments declined to <0.4 mmhos/cm by the second spring after the compost application, and EC levels were below levels toxic to plants.
Sediment Fractionation of Cu, Ni, Zn, Cr, Mn, and Fe in One Experimental and Three Natural Marshes
Authors: Lindau C. W. , Hossner L. R. 
Published: July 2010

AbstractDredged sediments from the Gulf Intracoastal Waterway near Galveston, Tex., were used as a substrate material in the construction of an experimental intertidal salt marsh. The objective of this research was to compare selected substrate properties of the experimental site with those of established marshes. Clay mineralogical properties of the experimental marsh were compared with those of three nearby natural marshes. A sequential chemical extraction procedure was used to obtain data on the partitioning of micronutrients and heavy metals among selected marsh substrate fractions.Clay minerals found in the sediments of the experimental marsh were equivalent to those identified in the natural marshes. Total elemental substrate concentrations of Cu, Ni, Cr, Zn, Mn, and Fe averaged 7.9, 8.6, 25.5, 25.2, 123, and 12,200 µg/g, respectively, over the four marsh sites. Copper, nickel, zinc, and chromium displayed only minor variations in substrate partitioning between the experimental and natural marsh samples. Micronutrients and heavy metal concentrations in the exchangeable and water‐soluble fraction were low compared with other fractions. Approximately 30% of the total substrate Cu, Ni, and Zn was associated with the organic matter fraction. Metals fixed within the lattice structures of clay and silicate minerals ranged from 20% Mn for experimental marsh samples to 90% Cr for one of the natural marshes. Major differences in Mn and Fe substrate partitioning were observed when the experimental marsh samples were compared with those of the natural marshes.
Comparison of the Soil Water Cycle in Clear‐Cut and Forested Sites
Authors: Kachanoski R. G. , de Jong E. 
Published: July 2010

AbstractA study was undertaken to determine the importance of subsurface flow and drainage in a northern Saskatchewan forested basin, and to examine the effect of clear‐cutting on the hydrologic cycle. Components of the soil water cycle were estimated for clear‐cut and forested sites during the spring melt and growing season. Surface runoff was measured using interceptor troughs and tipping‐bucket gauges. Soil water contents were measured using a neutron probe. Soil water fluxes were calculated using Darcy's Law and mass‐balance equations. Creek flow was monitored using a water‐level recorder and still well. Surface runoff was insignificant on all plots during the growing well. Surface runoff was insignificant on all plots during the growing season. Clear‐cutting increased hillslope water yield fivefold during the snowmelt period and doubled drainage during the growing season, compared with the forested site. Stream hydrographs indicated the basin was dominated by subsurface flow. This was consistent with measurement made on the forested plots where calculated drainage values could account for almost all observed streamflow. Hydrograph separation was carried out using mass‐balance calculations of Ca and Mg. The separation was used to identify sources of subsurface water contributing to streamflow.
Nitrate Depletion in a Second‐Order Mountain Stream
Authors: Swank Wayne T. , Caskey William H. 
Published: July 2010

AbstractThe amount of NO3‐N exported in a second‐order mountain stream draining a clearcut and logged mixed hardwood forest was studied over a 4‐year period. Calculations based on measurements of stream chemistry and discharge rates indicated a within‐stream depletion of NO3 from the upper reaches of the stream to the watershed outlet. Within‐stream depletion the first year of treatment was 127% of total NO3‐N discharged from the watershed outlet and declined in succeeding years after treatment to 99, 42, and 5%. Assays of the quantities of denitrifying enzymes in stream sediment samples suggested 1.7 kg N year−1 were lost via this pathway, compared with 3.9 kg N year−1 calculated from within‐stream depletion for the same time period. This study suggests sediment denitrification is a major pathway by which NO3‐N is lost. Within‐stream gaseous transformations are important when accounting for changes in N dynamics associated with forest management practices, and the measurement of only hydrologic discharge of NO3 could result in underestimation of N losses.
Heavy Metal Retention in Cattle Tissues From Ingestion of Sewage Sludge
Authors: Baxter John C. , Barry B. , Johnson D. E. , Kienholz E. W. 
Published: July 2010

AbstractCows and young steers were fed a diet containing 0 and 12% anaerobically digested Ft. Collins sewage sludge for 9 months, followed by a 4‐month withdrawal period during which no sludge was fed. Analyses of liver samples taken at intervals throughout the study showed that uptake of Cd, Cu, and Pb was linear with time. Cadmium increased from approximately 1 to about 20 ppm (dry wt) during the 9‐month sludge ingestion period. Lead and copper increased in liver tissues during the ingestion period; however, both decreased in a linear pattern after sludge was removed from the diet. There was no significant decrease of Cd levels in liver during the sludge withdrawal period. Zinc and iron levels in liver tissues were not affected by the sludge ingestion. Cadmium levels in kidney increased from approximately 5 ppm to approximately 55 ppm during the sludge ingestion period, with no significant decrease after sludge was removed from the diet. Lead and zinc concentrations in kidney increased during the sludge ingestion period, whereas Fe and Cu levels were not affected. Muscle tissues from cows and steers showed a slight, but significant, Cd increase during the sludge ingestion period. Cows showed no decrease in muscle Cd levels after the sludge withdrawal period, whereas muscle Cd concentrations of steers significantly decreased.The amount of sludge consumed by cattle during the course of this study was extreme, and would not occur under normal agricultural practices; however, even though large quantities of sludge were consumed, there were no apparent ill effects on animal health or performance.
Dissipation of Massive Quantities of 2,4‐D and 2,4,5‐T n‐Butyl Esters in Field Mini‐Lysimeters
Authors: Majka Joseph T. , Cheng H. H. , Muzik T. J. 
Published: July 2010

AbstractThe patterns of dissipation of 2,4‐D (2,4‐dichlorophenoxyacetic acid) and 2,4,5‐T (2,4,5‐trichlorophenoxyacetic acid) n‐butyl esters, applied in 1:1 mixtures at 560 or 2,800 kg/ha of each herbicide to soils in field mini‐lysimeters, were monitored periodically from December 1976 to April 1979. The lysimeters were located in Pullman, Wash., and packed with soils from Washington, Wyoming, and Mississippi. Both 2,4‐D and 2,4,5‐T were dissipated to < 1% of the initial concentration at the lower application rate in the Washington and Wyoming soils; however, at the higher application rate, dissipation of 2,4‐D was greatly impeded and dissipation of 2,4,5‐T was negligible in these soils. Dissipation of both herbicides in the acidic Mississippi soil was extremely slow even at the lower application rate. Surface soil pH was lowered following herbicide application. Some downward movement of both herbicides from the 0‐ to 5‐cm to the 5‐ to 10‐cm soil layer was evident. By the end of the experimental period, revegetation had begun only on the Washington and Wyoming soils treated at the lower application rate.
Heavy Metal Absorption by Winter Wheat Following Termination of Cropland Sludge Applications
Authors: Chang A. C. , Page A. L. , Bingham F. T. 
Published: July 2010

AbstractWinter wheat (Triticum spp. var. Anza) and soils were sampled at the third and the fourth year following the termination of sludge applications to a cropland site to examine the effect of deposited Cd and Zn on crop yield and metal concentrations in plants and the soil. Higher yields of wheat grain, due apparently to the residual N, P, micronutrients, and organic matter from the sludge treatment, were obtained from the sludge‐treated soils than from the controls. Although the treated soils received substantial quantities of Cu, Ni, and Pb, elevated plant‐tissue concentrations of these elements were not found in the wheat grain and straw. The plants, however, extracted greater amounts of Cd and Zn from the sludged than from non‐sludged fields. The metal contents of sludge‐affected wheat straw (0.07–0.16 µg/g Cd; 19–26 µg/g Zn) and grain (0.04–0.09 µg/g Cd; 22–45 µg/g Zn) were within the range typical for wheat grown on uncontaminated soils. Four years after the termination of sludge disposal, the heavy metals accumulated almost entirely in the 0‐ to 15‐cm soil layer where sludges were incorporated. The elevation of Cd and Zn did not result in any detectable increase in the concentration of water‐extractable Cd and Zn in the sludge treated soils. Attempts to recover heavy metals in the soil failed to account completely for all of the added metals. An average of 67% of the added metals was recovered from the surface 30 cm of the soil profile.
Survival and Growth of Pine Hybrid Seedlings With Pisolithus Ectomycorrhizae on Coal Spoils in Alabama and Tennessee
Authors: Berry C. R. 
Published: July 2010

AbstractContainer‐grown seedlings of specific pitch pine (Pinus rigida Mill.), loblolly pine (P. taeda L.), and pitch × loblolly pine (Pinus rigitaeda) hybrids were grown for 2½ years on unamended coal spoils in Alabama and Tennessee with Pisolithus tinctorius (Pt) ectomycorrhizae and, in separate plots, with naturally occurring ectomycorrhizae. The hybrid lines grew as well as or better than the loblolly or pitch lines. Seedlings with Pt ectomycorrhizae grew faster than seedlings with naturally occurring ectomycorrhizae. There was a significant genotype × mycorrhizal interaction at the Tennessee site. Trees with Pt ectomycorrhizae usually had lower concentrations of several elements in the foliage, including potentially toxic Mn, than trees with naturally occurring ectomycorrhizae. These data suggest that, on coal spoils, maximum benefit from Pt ectomycorrhizae can be obtained through selection of host genotypes known to be suited to the area and known to respond in a high degree to stimulation by the ectomycorrhizal fungus.
Uptake, Accumulation, and Translocation of Arsenical Compounds by Cotton
Authors: Marcus‐Wyner Lynn , Rains D. W. 
Published: July 2010

AbstractUptake, accumulation, and translocation of arsenic from different arsenical compounds were investigated in cotton plants (Gossypium hirsutum L. ‘SJ‐4’). Cotton plants grown in solution culture were exposed to arsenic trioxide (As2O3) from 0 to 8 µg As mL−1. Arsenic was readily taken up by the roots but was not translocated to the shoots. In contrast, when cacodylic acid (hydroxydimethylarsine oxide; (CH3)2As(O)OH) was applied in the range of 0–40 µg As mL−1, As was found not only in the roots but also in the leaves and reproductive structures. Plants treated with the herbicides MSMA (monosodium methanearsonate) and DSMA (disodium methanearsonate) also accumulated As in the roots and shoots. The defoliant, cacodylic acid, was applied as a foliar spray at the commercially recommendated rate of 1.4 kg/ha of cacodylic acid equivalents to cotton plants with green and mature bolls. Cottonseed from the treated bolls did not accumulae As above 2.6 µg As g−1, the tolerance limit. However, at higher application rates, the As concentrations increased in the cottonseed.Cotton plants grown in the greenhouse in Yolo clay loam (fine silty, mixed, nonacidic, thermic Typic Xerorthents) with a soil background level of 6 µg As g−1, were grown with cotton‐gin trash containing cacodylic acid at 0 to 53.5 µg As g−1 mixed into the soil. Analyzed plant samples contained < 0.05 µg As g−1 and did not accumulate or concentrate arsenic from the soil.
Determination of Algal‐available Phosphorus on Soil and Sediment: A Review and Analysis
Authors: Hegemann David A. , Johnson Arthur H. , Keenan John D. 
Published: July 2010

AbstractImportant advances have been made recently in identifying the sources of algal‐available P in soils and sediments. Algal bioassays have shown that considerable amounts of the total soil P may be algal‐available under the appropriate environmental conditions. At present, however, the reported research contains no convincing evidence that the bioassay techniques used quantitatively measured all of the algal‐available P present in the soils and sediments tested,. Although chemical fractionation procedures have shown from which fractions algae obtain P, there is no evidence that all of the chemically extracted P in those fractions is algal‐available. Quantitative assessment of algal‐available P in soils and sediments will depend upou the development of long‐term algal assay procedures.
Distribution of Cadmium, Zinc, Copper, and Lead in Soils of Industrial Northwestern Indiana
Authors: Miller W. P. , Mc Fee W. W. 
Published: July 2010

AbstractFive undisturbed locations of sandy Oakville and Plainfield soils under oak forest in the heavily industrialized region of northwestern Indiana were sampled at four depths, to assess the nature and extent of Cd, Zn, Cu, and Pb contamination. The litter layer and top 2.5 cm of soil at a site within 5 km of the center of the industrial complex were highly contaminated with Cd, Zn, Cu, and Pb. Levels of Cd and Zn decreased rapidly with distance to the south and east, while Cu and Pb decreased more erratically, with all metals reaching nearly background levels at 18 km. Samples taken deeper in the profiles (30 to 36 cm) did not show elevated metal levels compared with a rural site 67 km to the south. Sequential extraction methods applied to the top 2.5‐cm soil samples showed large amounts of relatively labile metals associated with exchange sites (KNO3‐extractable: 23, 10, 1, and 8% of total Cd, Zn, Cu, and Pb, respectively), bound by soil organic matter (Na4P2O7‐extractable: 21, 33, 24, and 41% of the total Cd, Zn, Cu, and Pb), and associated with carbonates and/or noncrystalline Fe oxides (EDTA‐extractable: 12, 8, 26, and 28% of the total Cd, Zn, Cu, and Pb). Minimal amounts of the metals were within the small amount of crystalline Fe and Mn oxides present in these soils. Non‐extractable (residual) metals amounted to 26, 32, 23, and 4% of the total Cd, Zn, Cu, and Pb.
Some Heavy Metals in Soils Treated With Sewage Sludge, Their Effects on Yield, and Their Uptake by Plants
Authors: Valdares J. M. A. S. , Gal M. , Mingelgrin U. , Page A. L. 
Published: July 2010

AbstractThe possible use of sludge with high heavy metal concentrations and at high rates in calcareous soil was demonstrated in this study. Mixtures of two sludges were added to soils in various proportions up to 4% sludge content. One sludge was rich in Ni and Cd, while the other was relatively poor in heavy metals. Three soils varying in pH from 7.7 to 5.5 were tested. The concentrations of Cd, Ni, Cu and Zn in the DTPA and saturation extracts of the soil‐sludge mixtures were determined and correlated with their uptake by plants and the yield of Swiss chard (Beta vulgaris L., cv. Ford Hook Giant) grown on these mixtures. The metal‐poor sludge hardly affected the yield of the relatively salt‐resistant Swiss chard. The metal‐rich sludge reduced the yield drastically in noncalcareous soils after a critical amount of that sludge (1.5%) was added to the soils. Yet, even 4% of this metal‐rich sludge increased the yield of Swiss chard, as compared with the sludge‐free control in a calcareous soil.The best fit to yield was obtained by multiple regression with metal content in the soil saturation extract. The solubility in soil solution of Cd, Ni and Zn was strongly affected by the pH. The uptake of Ni and Zn by plants was significantly larger in the acid soil than in the calcareous soil. The difference in the uptake of Cd and Cu between the soils was smaller. Plant uptake of the metals was generally predicted better by the total metal addition or concentration in the DTPA extract than by metal concentration in the soil saturation extract. In noncalcareous soils the total metal addition correlated as well as metal content in the DTPA extracts with the metal concentration in the soil solution, with the uptake by plants and with the yield.It has been known for some time that heavy metals introduced as mineral salts do not exhibit in soil the same behavior as heavy metals released from the sludge itself. The heavy metal contents in the soils were varied, therefore, by mixing the two sludges rather than by adding mineral salts to one sludge. Results of the relatively recent studies in which spiked sludges were used should be interpreted with care.
Effects of Ozone and Sulfur Dioxide on Tuber Yield and Quality of Potatoes
Authors: Foster K. W. , Timm H. , Labanauskas C. K. , Oshima R. J. 
Published: July 2010

AbstractAir pollution injury of the potato plant (Solanum tuberosum L.) has been documented previously, but potato yield losses have not been estimated in replicated experiments having controlled exposures to ozone (O3) and sulfur dioxide (SO2) A controlled‐environment study involving the speckle‐leaf‐sensitive cultivar ‘Centennial Russet’ was conducted to examine the effects of chronic exposure to O3 and SO2 on plant growth and tuber yield and quality.Ozone, at the highest seasonal dose (44.2 ppm‐h), reduced leaf dry weight 48%, root dry weight 58%, tuber number 38%, and total tuber yield 45%. Lower exposures affected these parameters in linear proportion to the O3 dose. Mean stem (minus leaves) dry weight, tuber dry weight, tuber dry matter percentage, partitioning of dry matter to tubers, and tuber sugar concentrations were not affected. Tuber N concentration increased linearly by up to 21% as the O3 dose increased. Plants grown outside of chambers in ambient air showed effects consistent with results obtained within the chambers. The plants grown outside received a total seasonal O3 dose of 50.4 ppm‐h and produced 58% less tuber yield than filtered air control plants.Plant responses to SO2 exposure were much less pronounced than their responses to exposure to O3. However, leaf symptom development in O3‐treated plants was markedly intensified by the presence of SO2. Small reductions in tuber yield and mean tuber size, but not in tuber number, were observed in SO2‐treated plants. Tuber N concentration increased slightly in SO2‐treated plants.A significant O3 × SO2 interaction was observed in the case of tuber N concentration only; SO2 accentuated the O3‐induced increase in N content.