bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effect of High 2,4‐D Concentrations on Degradation and Carbon Dioxide Evolution in Soils
Authors: Ou Li‐Tse , Rothwell D. F. , Wheeler W. B. , Davidson J. M.
Published: July 2010

A laboratory experiment was conducted to determine the degradation of high concentrations of 2,4‐D (2,4‐dichlorophenoxyacetic acid) and CO2 evolution in three soils. Two forms of 2,4‐D, technical grade and formulated, were added to each soil at rates of 50, 500, 5,000 and 20,000 µg/g of soil (ppm). Degradation of the 2,4‐D was measured by 14CO2 evolution resulting from the oxidation of uniformly ringlabeled carbon. At an application rate of 500 ppm, all three soils degraded 2,4‐D. At 5,000 and 20,000 ppm, degradation occurred in the Webster silty clay loam and Terra Ceia organic soil, but not in the Cecil sandy loam during 80 days of incubation. The degradation rate was generally higher for the formulated 2,4‐D than the technical grade material. For the higher 2,4‐D concentrations, 5,000 or 20,000 ppm, when extensive degradation occurred, total CO2 evolution was also greatly stimulated, and the pattern of total CO2 evolution rate exhibited a two‐peak response. Carbon dioxide‐carbon (CO2‐C) from the first peak appeared to be mainly from the formulation materials or from the impurities and CO2‐C from the second peak was mainly from 2,4‐D‐C.
Land Application of Chemically Treated Sewage Sludge: II. Effects on Plant and Soil Phosphorus, Potassium, Calcium, and Magnesium and Soil pH
Authors: Soon Y. K. , Bates T. E. , Moyer J. R.
Published: July 2010

Anaerobically digested sewage sludge resulting from treatment of sewage with Ca(OH)2, Al2(SO4)3, or FeCl, for phosphorus precipitation were applied at rates supplying up to 1,600 kg N/ha each year to corn (Zea mays L.) and bromegrass (Bromus inermis Leyess). Treatments with NH4NO3 supplying up to 400 kg N/ha were included.

Soil PH was increased by Ca‐sludge and reduced slightly by Fe‐sludge application. Phosphorus and magnesium concentrations in corn grain and stover were unaffected by treatment. Phosphorus concentration in bromegrass, and NaHCO3‐soluble soil P, were increased by Ca‐sludge and, to a lesser extent, by Fe‐sludge additions. The Ca‐sludge treatments resulted in a lower K concentration in corn stover and seedlings than either Al‐ or Fe‐sludge treatments. Increasing sludge or NH4NO3 application reduced K concentration in bromegrass. Both sludge and NH4NO3 applications decreased ammonium acetate‐extractable soil K in the bromegrass experiment. Sludge application had no effect on Ca concentration in corn grain or stover from Conestoga loam and Caledon loamy sand, but increased it in corn seedlings and stover from Oneida clay loam. Calcium in bromegrass was increased by sludge treatment with the Ca‐sludge having the greatest effect. Magnesium in bromegrass was increased by sludge and by NH4NO3 applications. The Ca‐sludge decreased Mg extracted by ammonium acetate from the loam and clay loam soils but not from the loamy sand.
Some Aspects of Sediment Distribution and Macrophyte Cycling of Heavy Metals in a Contaminated Lake
Authors: McIntosh A. W. , Shephard B. K. , Mayes R. A. , Atchison G. J. , Nelson D. W.
Published: July 2010

Distribution and forms of the metals cadmium (Cd) and zinc (Zn) in sediment and the possible significance of a die‐off of the aquatic macrophyte Potamogeton crispus in Cd cycling in a metal‐contaminated lake were studied. Metal levels in the upper 5 cm of lake sediment ranged from 2.54 ppm Cd and 115 ppm Zn in an uncontaminated area of the lake to 805 ppm Cd and 6,120 ppm Zn near the entrance of a metal‐bearing ditch to the lake. Evidence of metal contamination existed at a depth of 30 cm in sediments in contaminated areas of the system. Dominant forms present in the sediment were the carbonate for Cd and carbonate and organic for Zn. Analysis indicated Cd levels as high as 89.6 ppm in P. crispus in the lake with a maximum burden of 1.5 kg Cd held by the lake's P. crispus population. Release of the total amount could raise water concentrations by a maximum of 1 µg/liter.
Precipitation and Throughfall Chemistry in the San Francisco Bay Area
Authors: McColl J. G. , Bush D. S.
Published: July 2010

At Berkeley, California, main ionic constituents of bulk precipitation during the wet season of 1974–1975 were SO42‐, Cl−, HCO3−, Na+, and Ca2+, and mean H+ concentration was 10.7 ± 1.5 µeq/liter (pH 5.0). Although SO42‐ comprised 50% of the anions in bulk precipitation, H+ concentration had the highest correlation with NO3−. Impacted air pollutants accumulated on tree leaves between major rainstorms. Atmospheric N and S were correlated with NO3− and SO42‐ in bulk precipitation and leafwash in a Eucalyptus globulus forest. Ionic composition of bulk precipitation resembled that of surface‐soil solution in an adjoining, recently clear‐cut area.
The Effect of Waste Water Reuse in Cold Regions on Land Treatment Systems
Authors: Iskandar I. K.
Published: July 2010

The effect on ground water quality and soils and vegetation of treatment and disposal of municipal/industrial waste water on land in cold regions was investigated using six outdoor test cells. Winter application of waste water was feasible even at very cold air temperatures (<0.0°C) at the New Hampshire test site. High NO3‐N concentrations were observed in all treatments (5–15 cm/week) in both soils in early summer. This was explained as leaching of NH4‐N stored over the winter months after its oxidation to NO3 in early spring. Over the 12‐mo period of study, removal of organic C, BOD, suspended solids, fecal coliform bacteria, and phosphorus by the two soil types used (a Windsor sandy loam and a Charlton silt loam) was essentially complete. These had very little or no effect on ground water quality. The principal mechanism for nitrogen removal was found to be plant uptake, which was seasonally dependent. Application of 15− cm of secondary effluent per week to a sandy loam soil was not feasible because of the presence of > 10 mg/liter NO3‐N in the leachate for > 9 mo/year. Application of salts for road deicing during winter resulted in relatively higher concentrations of salts and Cl in the ground for a short period of time. No efforts were made to apply waste water according to plant need. Preapplication treatment is not necessary for the renovation of waste water by the soil‐plant systems. Movement of applied heavy metals to a depth of 15–30 cm in the high treatment soil was thought to be a result of a drop in soil pH resulting from this treatment. In all other treatments, heavy metals were confined to the top 15 cm of the soil.
Sulfur Distribution and Cycling in a Deciduous Forest Watershed
Authors: Shriner D. S. , Henderson G. S.
Published: July 2010

Sulfate sulfur concentrations and pH of precipitation and streamflow, and sulfur concentrations of biomass and soil components, were determined for a 97.5‐ha mixed deciduous forest (Walker Branch Watershed) in eastern Tennessee. Amounts of sulfur (S) added precipitation and lost by streamflow were compared to fluxes of S between biomass pools. Approximately 18.1 kg/ha per year entered the watershed from the atmosphere, while only 11.5 kg/ha per year were lost in streamflow. Analysis of biomass and soil concentrations of S indicate that, of the 6.6 kg/ha per year apparent accumulation of S for the watershed as a whole, 8.6 kg accrue to mineral soil while 4.3 kg are lost from organic soil horizons, and 2.3 kg accrue to annual increment of vegetation.

Seasonal variations in S input and export from the watershed were closely tied to precipitation events. The weighted mean pH of the rainfall samples collected at five sampling sites on the watershed was pH 4.2. Sulfate accounts for 80% of major anions (millequivalent basis) contributed to the watershed. The behavior of S on Walker Branch Watershed appears to differ significantly from locations in the northeastern U.S., however the data suggest active expansion to the southeastern U.S. of the area impacted by atmospheric sulfate pollution commonly associated with the northeastern region of the U.S.
Crop Response and Quality of Soil Leachate as Affected by Land Application of Beef Cattle Waste
Authors: Haghiri F. , Miller R. H. , Logan T. J.
Published: July 2010

A single application of beet cattle manure at rates of 0, 49, 158, and 316 dry metric tons/ha to field lysimeters containing three different soil types was made. Corn (Zea mays L.) yields for the frst and second years reached the maximum at the 158‐metric tons/ha manure rate, while in fourth year the highest yield was obtained at the 316‐metric tons/ha rate. With the exception of first cropping years, at the 49‐metric ton rate yields of dry matter produced were ≤ the control which received fertilizer annually. Corn yields for all years and from all manure treatments were significantly higher for the Wooster (Typic Fragiudalf) soil compared with Celina (Aquic Hapludalf) and Hoytville (Mollic Ochraqualf) soils. Nitrate‐N concentration in the leachate increased with increasing load of applied manure and decreased with time after application. More NO3‐N was leached from the manure‐amended Wooster soil than from the other two soils over a 4‐year period. The decomposition of manure was higher in the Celina and Wooster soils than in the Hoytville soil. The application of beef cattle manure to soils did not influence the incidence of soil‐borne plant pathogens. The results of this study indicate that annual application of beef cattle manure to soils at <50 dry metric tons/ha is far more desirable than single application of high loading rates for 2‐ to 3‐year periods from the standpoint of maximizing plant nutrient use and water quality.
Correlation of Extractable Metals and Metal Uptake of Snap Beans Grown on Soil Amended with Sewage Sludge
Authors: Latterell J. J. , Dowdy R. H. , Larson W. E.
Published: July 2010

A field study was conducted in which anaerobically digested sludge was applied to sandy Udorthentic Haploboroll soil as single applications (0, 112, 225, and 450 metric tons/ha) or as three annual sludge applications (accumulated total 0, 350, 700, and 1,400 metric tons/ha). In both cases sludge‐borne trace metals removed by several chemical extractants were correlated to trace metal uptake by snap beans (Phaseolus vulgaria L., Cv. Tendergreen) and soil organic matter. A highly significant linear correlation was found between: (i) DTPA‐, KNO3‐, Na4P2O7‐, and NH4C2H3O2‐extractable Zn and Zn concentrations in edible bean tissue, bean leaf tissue, and organic matter; (ii) DTPA‐, Na4P2O7‐, and NH4C2H3O2‐extractable Cu and Cd and their concentrations in edible bean tissue and organic matter; (iii) DTPA‐, Na4P2O7‐, and NH4C2H3O2‐extractable Ni and Pb and organic matter; and (iv) Na4P2O7‐extractable Cr and organic matter. Pyrophosphate extracted the highest percent of applied metal, except for Ni where the Na4P2O7 and DTPA extracted approximately equal quantities. Except for Cr, a highly significant correlation was observed between Na4P2O7 and DTPA or NH4C2H3O2‐extractable metal. A highly significant linear correlation was found for the 4‐year period between DTPA‐extractable Zn and Cu and their concentrations in edible bean tissue, bean leaf tissue, and organic matter. For the single application series the maximum percentage of applied Zn and Cu was extracted during the second year.
The Pesticide Content of Surface Water Draining from Agricultural Fields—A Review
Authors: Wauchope R. D.
Published: July 2010

The literature on pesticide losses in runoff waters from agricultural fields is reviewed. For the majority of commercial pesticides, total losses are 0.5% or less of the amounts applied, unless severe rainfall conditions occur within 1–2 weeks after application. Exceptions are the organochlorine insecticides, which may lose about 1% regardless of weather pattern because of their long persistence; and soil surface‐applied, wettable‐powder formulations of herbicides, which may lose up to 5%, depending on weather and slope, because of the ease of washoff of the powder.

Pesticides with solubilities of 10 ppm or higher are lost mainly in the water phase of runoff, and erosion control practices will have little effect on such losses. Organochlorine pesticides, paraquat, and arsenical pesticides, however, are important cases of pesticides which are strongly adsorbed by sediments, and erosion control can be important in controlling losses of these compounds.

The behavior and fate of pesticides in streams receiving runoff is generally not known. Information on such factors as time and distance of impact of a given runoff event, ability of local ecosystems to recover from transient pesticide concentrations, and dissipation or concentration processes in aquatic ecosystems will have to be obtained before “edge‐of‐field” pesticide losses can be related to water quality in receiving waters.
Chemical and Biological Phenomena Observed with Sewage Sludges in Simulated Soil Trenches
Authors: Taylor J. M. , Epstein E. , Burge W. D. , Chaney R. L. , Menzies J. D. , Sikora L. J.
Published: July 2010

Chemical and biological observations were made on sewage sludge in a simulated trenching system in the greenhouse. Limed and unlimed raw and digested sludges were placed in simulated trenches in soil profile boxes in which corn (Zea mays L.) was sown. During the 160‐day growth period, roots penetrated entrenched digested sludge and root growth proliferated throughout the sludge. Root penetration into the raw sludges was severely restricted. Gas analysis showed that anaerobic conditions prevailed for extensive periods during the 160 days in raw sludge. Methane and CO2 levels reached 45 and 25%, respectively. The levels of CH4 and CO2 were < 3 and 21%, respectively, in the digested sludge boxes. Nitrate nitrogen, adjacent to and beneath the sludge, was generally higher with digested than with raw sludge. Zinc and copper did not move from the sludge into the surrounding soil. The increase of these metals in corn leaves was relatively low, reaching only 131 µ/g Zn and 5.9 µ/g Cu as compared with 79 µ/g Zn and 3.8 µ/g Cu in the controls. Although low levels of fecal coliforms survived in the sludge, none were found in the soil surrounding the sludge. Total coliform numbers in the sludge after 160 days were negatively correlated with NH3‐N concentrations, suggesting that NH3, generated on dissociation on NH4+, may be important in reduction of human pathogens.
Adsorption Kinetics of Bacteriophage ΦX‐174 on Soil
Authors: Burge W. D. , Enkiri N. K.
Published: July 2010

The adsorption of bacteriophage ΦX‐174 by a soil followed classical square‐root‐of‐time kinetics, indicating that the rate of adsorption was controlled by diffusion. These results, however, are explained by the heterogeneity of the virus population relative to adsorption rate. The presence of at least two virus populations distinguishable by the rates at which they are adsorbed by the soil and desorption of the adsorbed virus upon dilution are demonstrated experimentally.
Stream Chemistry and Watershed Nutrient Economy Following Wildfire and Fertilization in Eastern Washington
Authors: Tiedemann A. R. , Helvey J. D. , Anderson T. D.
Published: July 2010

During the first 3 years after a severe wildfire in 1970, maximum concentrations of nitrate‐N (NO3‐N) in stream water increased from prefire levels of <0.016 to 0.56 mg/liter on a burned, unfertilized watershed and to 0.54 and 1.47 mg/liter on two watersheds that were burned and fertilized. Maximum NO3‐N concentration in the stream from an unburned watershed was 0.066 mg/liter. Since NO3‐N levels in the stream from the burned‐only watershed were similar to burned‐fertilized watersheds, increased levels appear to be primarily a result of increased nitrification. Organic N concentrations in streamflow were nearly doubled during the second year after fire compared to prefire levels.

Concentrations of total phosphorus (T‐P) in streams from one burned and two burned‐fertilized watersheds were 1.5 to 3 times greater than from an unburned watershed. Combined concentrations of Ca, Mg, K, and Na in streams prior to fire ranged from 12.0 to 14.9 mg/liter. Concentrations declined to 7.4–10.5 mg/liter in streams from burned and burned‐fertilized watersheds during the second year after fire (1972) because of dilution resulting from increased discharge and were still less in 1975 than prefire levels (8.4 to 12.7 mg/liter).

Average inputs of N, P, and the four cations during the 5 years of study were 1.23, 0, and 3.56 kg/ha per year. Yearly N input from precipitation was sufficient to balance solution losses in three of the five postfire years. Cation losses in solution greatly exceeded precipitation inputs in all years.

Relative to background conditions and levels observed in the control stream, the fire exerted protracted impacts on the chemistry of these streams. Results however, indicate that fire and fertilization exerted negligible effects on chemical water quality for municipal use.
Incineration of Pesticides Containing Phosphorus
Authors: Ahling Bengt , Wiberger Kerstin
Published: July 2010

Fenitrothion and malathion are commonly used as pesticides in farming and gardening. Residues of these compounds can be found in wastes from these activities, such as sprayed material and packaging. This report describes experiments carried out to investigate the possibility of destroying these wastes by incineration. The investigations show that combustion of fenitrothion and malathion at low temperatures (<600°C) gives emissions of 1–2% of the amount of pesticide introduced. To insure safe destruction (emission <100 mg unburned/kg introduced), a temperature above 700°C and a transit time of 3–4 sec are needed. In the case of shorter transit times, the temperature should exceed 800°C.
A Review of the Environmental Impact of Ground Disposal of Oil Shale Wastes
Authors: Routson R. C. , Wildung R. E. , Bean R. M.
Published: July 2010

The development of oil shale reserves in the western U.S. could contribute greatly to energy independence and several oil extraction processes are feasible. However, the industry remains in initial stages of development, due, in part, to environmental issues. This review considers waste disposal methods for the major types of extraction processes, the potential environmental impacts of waste disposal to the ground, mitigation of environmental effects, and further research needs.

Principal waste products of oil shale extraction constitute up to 125% of the original volume, and disposal may, therefore, affect vast land areas. Principal wastes scheduled for ground disposal include the waters produced during retorting and subsequently separated from the shale oil and the spent shales remaining after extraction. Retort waters contain relatively high concentrations of complex, soluble organic components and the spent shales contain potentially leachable salts and organic pyrolytic products. In addition, spent shales have erosion potential when disposed on the surface and considerable effort is being directed to shale management, emphasizing erosion control and shale as a growth medium, and revegetation methods for establishing salt‐ and drought‐tolerant plant species.
The Distribution of 239,240Pu, 238Pu, and 137Cs in Various Particle Size Classes of Lake Michigan Sediments
Authors: Alberts James J. , Muller Robert N.
Published: July 2010

The distribution of 238Pu, 239,240Pu, and 137Cs was determined in sediment samples from Lake Michigan which had been separated into various particle size classes by an elutriation technique. Within the range of size classes studied the distribution of these isotopes are not a function of particle size, but rather have a constant concentration. In addition, calculations of ratios of 239,240Pu and 137Cs concentrations on particles to their concentration in the overlying water showed: (i) the ratios are similar for both plutonium and cesium (∼105); and (ii) ratios do not vary with particle size for either element.
Nitrate Movement in a Chilean Agricultural Area Irrigated with Untreated Sewage Water
Authors: Schalscha E. B. , Vergara I. , Schirado T. , Morales M.
Published: July 2010

Nitrate concentrations in soils and drainage and well waters were determined in a 15‐ha field representing about 4,000 ha of agricultural land irrigated exclusively with raw sewage water for > 25 years. Analyses of the percolating water below the root zone indicated that the leached NO3−‐N was about 350 kg/ha per year. The transit time for water to move through the unsaturated zone to the saturated zone at a depth of 2 to 2.2 m was < 1 year, and the leaching fraction was estimated as 0.63. Concentrations of NO3−‐N ranged from 20 to 35 mg/liter in the percolating water of the unsaturated zone, whereas two well waters contained 9 and 14 mg/liter.
Influence of Simulated Rainfall on the Retention of Sludge Heavy Metals by the Leaves of Forage Crops
Authors: Jones S. G. , Brown K. W. , Deuel L. E. , Donnelly K. C.
Published: July 2010

The land disposal of municipal liquid digested sludge by surface application to a growing forage crop may cause foliage to become coated with sludge. The ingestion of foliage contaminated with sludge could be detrimental to the health of grazing animals, since municipal sludges often contain potentially toxic amounts of various heavy metals. The influence of simulated rainfall, leaf morphology, and sludge solids concentration on the retention of sludge heavy metals by the foliage of grasses was evaluated.

Liquid digested sludges, containing 2 and 4% solids, were applied to greenhouse flats of common bermudagrass (Cynodon dactylon L.) and Bell rhodesgrass (Chloris gayana Kunth.), equivalent to depths of 2.50 and 1.25 cm, respectively. Sludge‐treated grasses were subjected to simulated rainfall equivalent to 2.5 cm/hour either immediately following sludge treatments or after 24 hours of drying. Additional flats receiving the sludge treatments were sampled at regular intervals over a 2‐week period to determine the foliar retention of sludge in the absence of rainfall.

The foliage of both grasses was visibly contaminated with sludge following application. The foliar concentrations of Cd, Cu, Pb, and Zn were measured for each sludge treatment. There appeared to be no preferential retention of any particular heavy metal. Bell rhodesgrass retained more sludge than common bermudagrass because of its larger leaf blades and overlapping sheathes. The sludge containing 4% solids was retained by the foliage to a greater extent than sludge containing 2% solids.

Sludge that was not allowed to dry on the leaves was removed by 1.25 cm of simulated rainfall, regardless of the grass species or sludge solids concentration. Sludge that was allowed to dry on the leaves, however, was not removed by 2.50 cm of simualted rainfall.
Waste Wood Fiber as a Soil Amendment
Authors: King Larry D.
Published: July 2010

Byproducts from wood processing have been used as soil amendments for many years. This study was conducted to determine the effects of a relatively new wood byproduct on plant growth and soil properties. Waste wood fiber containing 2% N (mainly as urea‐formaldehyde used as a binding agent in fiberboard production) was applied to sandy loam and clay loam soil materials in a greenhouse study. Single applications of 2,4, and 6% by weight of fiber were compared over a 2‐year period to six applications of 25, 50, and 100 ppm of fertilizer N to soils receiving no fiber.

Fiber did not increase yields of fescue grass (Festuca arundinacea Schreb.) at the first harvest but did increase yields for 8 to 10 mo thereafter. By the seventh harvest the single application of 4% fiber (supplying 800 ppm N) produced a cumulative yield equal to the yield with six 50‐ppm N applications. Yields with the 6% fiber rate (supplying 1,200 ppm N) were 80% of the yields obtained from six 100 ppm N applications. Fiber additions increased available soil moisture (between 0.1 and 15 bars), cation exchange capacity, organic matter, and total N, and lowered bulk density.
An Extended Version of a Conceptual Model for Evaluating Annual Nitrogen Leaching Losses from Croplands
Authors: Tanji K. K. , Broadbent F. E. , Mehran M. , Fried M.
Published: July 2010

Previously, a steady‐state conceptual N model was applied to corn (Zea mays L.) field trials at two University of California Field Stations. That model examined only the inputs and outputs of N into a soil‐plant‐water system without considerations of carryover inorganic soil N and mineralization of organic soil N. It predicted N leaching losses reasonably well in the corn plots at the Kearney site where residual soil N was low, but not for the Davis site where considerable mineralization of soil organic N occurs.

This steady state model was extended so that it would be applicable to the transient conditions prevailing at the Davis site. The revisions included provisions for the presence of residual inorganic soil N and the mineralization of organic soil N as well as inputs of organic N such as manures and sewage sludges and their mineralization rates. The original water submodel was not modified. The model is described in the appendix and required input parameters with examples are listed.

The revised model was tested with 2 years of corn field trials at Davis which consisted of four (NH4)2SO4 rates (0, 90, 180, and 360 kg N/ha) and three irrigation regimes (1/3, 3/3, and 5/3 of the corn evapotranspiration). Sensitivity analysis evaluated the importance of the harvested crop coefficient, the denitrification coefficient, and the mineralization rate constant for organic soil N, and aided in estimating the latter two experimentally unmeasured parameters.

Computed results compared favorably with measured N content in the harvested (grain and stover) crop, the residual inorganic soil N after harvest, and the average annual N concentration in the soil solution beneath the root zone at the 3‐m depth. There was no leaching of N in the 1/3 ET treatment; from 0.5 to 12 kg N/ha per year N leaching losses in the 3/3 ET treatment; and from 13 to 144 kg N/ha N leaching losses in the 5/3 ET treatments. Some differences were noted in the annual leaching losses between the 1975 and 1976 corn crops in the 5/3 and 3/3 ET treatments mainly due to differences in seepage out of the root zone.

It is concluded that the applicability and utility of this expanded model have been significantly enhanced over that of the previous steady‐state model.
Programmed Impacts of Environmental Restraints Applied to U.S. Agriculture
Authors: Heady Earl O. , Vocke Gary
Published: July 2010

A national and interregional programming model is developed to evaluate the impact of potential restraints for soil loss and nitrogen on land use, crop production patterns, interregional competition, and economic variables. The model includes 105 producing regions with 5 land classes in each, 51 water supply regions, and 28 market regions. Crop and soil loss activities are defined for each land class in each producing region. The soil loss restraints would reduce gross soil loss through use of more contouring, strip cropping, terracing, and minimum tillage. Interregional reorganizations of agriculture are predicted to occur. Regions with greater rainfall and hilly land, particularly the southeastern U.S., would sacrifice in cropping share and farm income. Regions of level lands and less rainfall, particularly the Great Plains and part of the Corn Belt, would gain in cropping intensity and income. Under nitrogen restrictions more hectares of crops would be grown and pesticide expenditures would increase. Under all environmental alternatives analyzed, U.S. agriculture could meet U.S. food needs with small increases in the supply prices of food.
Hydrology and Chemical Quality of Flow from Small Pastured Watersheds: I. Hydrology
Authors: Van Keuren R. W. , Mc Guinness J. L. , Chichester F. W.
Published: July 2010

Surface runoff, soil loss, and subsurface flow were measured from four rotationally grazed summer pastures. One of these pastures was also used as a winter‐feeding area. Surface runoff volumes and peak rates from the three pastures used only for summer grazing were generally less as compared with values for earlier years when the fields were in meadow and fight pasturing; however, runoff from the winterfeeding area was markedly increased. Both before and after the initiation of grazing, the areas used only for summer grazing had but a trace of soil loss. More soil was lost from the winter‐feeding area, particularly during the dormant season. Water‐balance studies indicated that during the growing season surface runoff and subsurface outflow were higher and evapotranspiration (ET) was less from the winter‐feeding area than from areas summer‐grazed only. During the dormant season, surface runoff was higher and subsurface outflow was lower from the winter‐feeding area than from the summer‐grazed areas, whereas ET was similar.
Statistical Considerations and Survey of Plutonium Concentration Variability in Some Terrestrial Ecosystem Components
Authors: White Gary C. , Hakonson Thomas E.
Published: July 2010

Statistical aspects of the use of the coefficient of variation (c) in the design of environmental plutonium studies are considered. Small sample properties of the estimate of c are studied for both normal and log‐normal populations with Monte Carlo simulations. A minimum sample size of 50 is necessary to estimate c with much precision, and an estimate of c from a sample size of less than 5 is nearly worthless. The difficulty of achieving good estimates of c increases as the true value of c increases.

In addition, some of the available data on the variability of plutonium concentrations in terrestrial ecosystem components is summarized. The data were pooled to achieve better estimates of the coefficient of variation than might be available from individual studies. Pooled estimates of c are: soils, 1.35; vegetation, 0.70; and rodent tissues, 1.10. The estimates of c presented should be useful in designing a field sampling program for plutonium.
Occurrence and Stability of Calcite in the Maumee River
Authors: Green Dan B. , Smeck Neil E.
Published: July 2010

The occurrence of secondary (precipitated) calcite and the concentrations of parameters controlling calcite dissolution‐precipitation were monitored at six sites in the Maumee River drainage system during 1975–76. Secondary calcite was identified on the basis of calcite/dolomite ratios as determined by X‐ray diffraction and a volumetric procedure employing the Chittick apparatus. Additional evidence for the occurrence of secondary calcite as well as crystal morphology was obtained by optical microscopy. A positive correlation between nigh calcium concentrations and the occurrence of secondary calcite could not be established; however a relationship between algal blooms and calcite formation was noted. It is concluded that a reduction in the CO2 content of the stream due to algal biomass production is the factor responsible for initiating calcite precipitation in the Maumee River system. Calcite equilibria in the stream is quite dynamic with secondary calcite appearing and disappearing in relatively short periods of time.
Extent and Distribution of Soil Heavy Metal Contamination near a Nickel Smelter at Coniston, Ontario
Authors: Rutherford G. K. , Bray C. R.
Published: July 2010

The extent of contamination in surface soils and profiles by sulphur compounds and the heavy metals nickel, copper, zinc, and iron up to a distance of 3.5 km in the southeast quadrant from the smelter at Coniston, Ontario, has been examined. Total and sulphate sulphur were measured, as well as total, available, and exchange heavy metals. Strong contamination by Ni, Cu, total S, and sulphate, and mild contamination by Zn and Fe, was recorded for the upper Soil horizons. The Mean pH value for these soils is about 3.7.

The distribution of contaminants in surface soil was examined by use of a site‐specific soil classification and by analyses of site variables using linear regression and SYMAP. Site variables of most import were: distance from the smelter, exposure of the site with respect to the smelter, and soil drainage status.
Solute Movement from Fluidized Bed Combustion Waste in Acid Soil and Mine Spoil Columns
Authors: Sidle R. C. , Stout W. L. , Hern J. L. , Bennett O. L.
Published: July 2010

Fluidized bed combustion waste (FBCW), a by‐product from a specialized coal‐fired power plant, was used as a liming source to determine its impact on solute transport in the soil. The upper 10 cm of 60‐cm‐long acid silt loam soil (pH 4.6) and strip mine spoil (pH 4.1) columns was treated with enough FBCW to raise the pH of the two media to 5.0 and 6.0, and 4.6 and 6.0, respectively. Loadings of Ca, S, and Mg in the upper 10 cm of the pH 6 mine spoil treated were 1,132, 309, and 46 µg/g soil, respectively. Approximately twice these loadings were applied to the upper 10 cm of the acid soil columns. Heavy metal loading rates were very low in all treatments. Columns were leached with 10 cm of water at 10‐day intervals 7 and 14 times. Percolate samples collected from mine spoil columns treated with FBCW showed no evidence of enhanced levels of Al, B, Ca, Cd, Cr, F−, Cu, Fe, Mg, Mn, Ni, P, Pb, SO42‐, Sr, and Zn after 14 leachings. Acid soil columns, containing higher levels of organic matter, had percolate concentrations of Ca, Mg, Mn, and SO42‐ that increased with increasing FBCW liming applications. None of the analyzed constituents showed any evidence of downward migration in mine spoil matrix and only Ca moved downward into the 10‐ to 15‐cm depth of the soil matrix.
The Influence of Anion Mobility on Ionic Retention in Waste Water‐irrigated Soils
Authors: Johnson D. W. , Breuer D. W. , Cole D. W.
Published: July 2010

The concept of anion mobility as a determinant of soil leaching rate was illustrated in a waste water irrigation study. Anion adsorption appeared to affect the leaching of H2PO4− and SO42‐, but not Cl−, which percolated freely through the soil. The mobility of NO3− was primarily regulated by nitrification and plant uptake. The most pronounced change in solution chemistry was an alkalinity decrease of approximately 80% as waste water entered the soil due to lowering of pH (7.5 to ca. 6.5), and to gaseous CO2 loss from solution. This alkalinity decrease accounted for most of the total ionic retention in the soil which ranged from 40–60% of waste water input.
Concentrations of Coumestrol and 4′ ,7‐dihydroxyflavone in Four Alfalfa Cultivars after Exposure to Ozone
Authors: Skärby L. , Pell E. J.
Published: July 2010

Ozone can induce increases of 4′ ,7‐dihydroxyflavone (4′ ,7‐DHF) but not coumestrol in the ‘Buffalo’ alfalfa cultivar. This study was designed to determine whether these responses were unique to ‘Buffalo’ or characteristic of other alfalfa cultivars. Seven‐week‐old seedlings of ‘Ladak,’ ‘Sonora,’ ‘Moapa,’ and ‘Vernal’ alfalfa cultivars were exposed to 773 µg/m3 (0.40 ppm) ozone for 3 hours. Forty‐eight hours after exposure, all foliage exhibiting chiorosis to extensive necrosis were harvested. Similar‐aged foliage from non‐ozonized control plants was also harvested. Methanolic extracts of the tissue were prepared and the presence and quantity of coumestroi and 4′,7‐DHF determined. Coumestrol was not detected in control or ozonized tissue. Nonozonized tissue was free of detectable 4′,7‐DHF. Injured foliage of all four cultivars contained elevated levels of 4′,7‐DHF as high as 91 ppm. There were no significant differences in concentrations of 4′,7‐DHF when concentrations were compared in four ozonized cultivars.
Kinetics of the Reaction Between Orthophosphate Ions and Muskegon Dune Sand
Authors: Novak L. T. , Petschauer F. J.
Published: July 2010

This paper presents data on the kinetics of orthophosphate adsorption on Muskegon dune sand. The data was obtained using batch experiments with shaken flasks followed by centrifuging and standard techniques for orthophosphate determination. Data is also presented for orthophosphate breakthrough from packed columns of dune sand.

Three mechanistic kinetic models were evaluated against the batch adsorption data over the 0‐ to 24‐hour period: (i) LPDF model for interparticle mass transfer followed by a first order irreversible surface reaction; (ii) Langmuir kinetics followed by a first order irreversible surface reaction; and (iii) solid phase diffusion model for intraparticle mass transfer. Both models (i) and (ii) describe the fast and flow reactions occurring over the 24 hours studied. Model (ii) is favored partly because the sum of the square error in model (i) is 41% greater than the same for model (ii). Model (iii) does not describe the adsorption data during the 24‐hour period studied.

Based on dune sand chemical composition data, and the length of the fast reaction period, it appears that the major reaction occurring during orthophosphate adsorption may involve calcite. Model (ii) is shown to be consistent with the general theory of orthophosphate calcite adsorption proposed by W. Stumm and J. O. Leckie (1970).
Sand Filtration of Poultry‐Processing Lagoon Effluent
Authors: Whitehead W. K.
Published: July 2010

About 100 poultry processing plants in the United States have private waste treatment systems—predominantly stabilization ponds or lagoons. To meet the proposed USEPA regulations for waste discharges, the effluent from many of these systems must be improved. Pilot‐scale, gravity‐flow sand filters were tested as a means of further treating poultry processing lagoon effluent. Waste water application rates ranged from 0.23 o 1.40 m3/m2 per day. Average BOD5 reductions varied from 57 to 27% and average suspended solids were reduced from 52 to 37%. Effluents from the 0.23‐ and 0.47‐m3/m2 per day filters were in compliance with proposed 1983 EPA regulations for BOD5 and suspended solids during the summer and fall months. Filters with waste water applied at rates of 0.23, 0.47, and 0.94 m3/m2 per day performed for over 1 year without being cleaned.
Growth of Rye Grass and Fescue as Affected by Lead‐Cadmium‐Fertilizer Interaction
Authors: Carlson Roger W. , Rolfe Gary L.
Published: July 2010

Rye grass (Lolium perenne L.) and red fescue (Festuca rubra L.) were grown from seed in fertilized (NPK, 12:6:6) and unfertilized Flanagan silt loam soil treated with Pb (0, 10, 100, 1,000, 5,000, 10,000 µg g−1), Cd (0, 0.1, 1, 10, 50, 100 µg g−1), or a combination of Pb plus Cd at a ratio of 100 Pb:1 Cd. Plant growth and heavy metal content of plants were measured at the end of three, consecutive, 10‐day periods. Growth of Pb‐treated plants did not begin to decrease until treatment concentrations reached 1,000 µg g−1 Pb or above. Above a treatment concentration of 1,000 µg g−1 Pb with or without added Cd, growth was reduced sharply in a log‐linear fashion with increasing treatment concentrations. Some reduction in growth of plants treated with Cd alone occurred for fertilized rescue above 10 µg g−1 Cd but not for rye until treatments above 50 µg g−1. No reduction in growth was found for nonfertilized plants treated with Cd alone at the highest soil concentration (100 µg g−1). Reduction in growth for plants treated with Pb + Cd was no lower than that of plants treated with Pb alone. While fertilization stimulated growth at treatment concentrations < 1,000 µg g−1, it did not ameliorate the effects of Pb at higher concentrations. Fertilization reduced Pb content and uptake in rye (P < 0.001) but not in fescue. The Cd content of fertilized plants was greater (P < 0.05) than that of nonfertilized plants. Cadmium content of plants treated with Pb + Cd was greater (P < 0.05) than that of plants treated with Cd alone, while there was no difference in Pb content between Pb and Pb + Cd treatments.
An Ecosystem Approach to the Treatment of Waste Waters
Authors: Lakshman G.
Published: July 2010

Aquatic plants such as bulrush (Scirpus spp) and cattail (Typha spp) were used to purify untreated municipal sewage in experimental tanks in a growth chamber measuring 5.5 by 3.7 by 3.7 m high. Initial concentrations of total phosphorus (TP) and total Kjeldahl nitrogen (TKN) before treatment ranged from 3.9 to 29.0 ppm for TP and from 10.3 to 44.0 ppm for TKN. Rates of removal of phosphorus and Kjeldahl nitrogen by the plants were monitored and compared with a control without plants. Generally, the concentrations of TP and TKN decreased exponentially in the treatment trays during the individual experimental runs. High rates of purification, up to 98%, were achieved in <20 days. During the 20 experimental runs lasting >500 days the plants showed unabated ability to remove nutrients while the control achieved a saturated condition.

Rates of nutrient uptake by the experimental plants increased with the ambient concentration and were much faster than the rates predicted by Michaelis‐Menten kinetics. Above‐water biomass obtained by periodic harvesting showed that the plants contained high levels of digestible organic matter (DOM) and crude protein comparable to the values obtainable from alfalfa. Experimental data have been used to develop equations for large‐scale in situ applications. Data presented here show that aquatic plants have considerable potential in the purification of municipal waste waters within reasonably short periods.
Metabolism of Carbofuran in Rice Straw‐amended and Unamended Rice Soils
Authors: Venkateswarlu K. , Sethunathan N.
Published: July 2010

Degradation of carbofuran (2,3‐dihydro‐2,2‐dimethyl‐7‐benzofuranyl N‐methylcarbamate) in rice straw‐amended flooded soil under alternate anaerobic‐aerobic conditions and 14CO2 evolution from ring‐ and carbonyl‐labeled 14C‐carbofuran in flooded soil were studied. The addition of rice straw accelerated the hydrolysis of carbofuran to carbofuran phenol (2,3‐dihydro‐2,2‐dimethyl‐7‐hydroxy benzofuran) in predominantly anaerobic flooded soil. Carbofuran phenol appeared to accumulate under continued anaerobiosis and was readily decomposed with the significant formation of unextractable (“soil bound”) residues when the system was returned to aerobic conditions. Interestingly, 14CO2 evolution from the aromatic ring in carbofuran was almost negligible, accounting for <0.3% of ring‐14C even after 40 days of flooding as compared to 27% released from carbonyl‐14C.
Injury and Yield Responses of Spinach Cultivars to Chronic Doses of Ozone in Open‐Top Field Chambers
Authors: Heagle A. S. , Philbeck R. B. , Letchworth M. B.
Published: July 2010

Spinach (Spinacia oleracea L.) cultivars were exposed continuously during growth to carbon‐filtered air or nonfiltered ambient air in open‐top field chambers. Constant low concentrations of ozone (O3) were added to the varying ambient concentrations in the nonfiltered‐air chambers for 7 hours (0920 to 1620 EDT) per day. There were significant differences in the amount of foliar injury and shoot growth decrease among 11 spinach cultivars exposed for 7 hours/day to 0.13 ppm of O3; America, Winter Bloomsdale, and Seven‐R were less sensitive to foliar injury than Chesapeake, Hybrid‐612, and Dixie Market. Shoot growth of America and Viroflay was affected less and Hybrid‐612 and Dark Green Bloomsdale more than that of most other cultivars. The cultivars America, Winter Bloomsdale, Hybrid 7, and Viroflay were exposed for 38 days to determine threshold doses of O3 for injury and yield effects. The threshold 7‐hour/day mean O3 concentration for foliar injury was between 0.02 and 0.06 ppm. The threshold for a significant decrease in shoot growth of most spinach cultivars was between 0.06 and 0.10 ppm. Shoot fresh weights of plants grown in the ground at 0.06, 0.10, and 0.13 ppm were 18, 37 and 69% less, respectively, than plants grown at 0.02 ppm. Comparative values for potted plants grown in a 1:1:1 mixture of sand/soil/Pro‐Mix BX were 4, 25, and 65%, respectively.
Americium‐241 Uptake by Bahiagrass as Influenced by Soil Type, Lime, and Organic Matter
Authors: Hoyt G. D. , Adriano D. C.
Published: July 2010

Availability of 241Am to bahiagrass (Paspalum notatum), a major forage crop in the southeastern U.S., was studied under greenhouse conditions using two soil types, two rates of lime, and four rates of organic matter. The plants were grown in pots until three clippings were obtained.

Americium‐241 concentrations in plant tissues from the unlimed Dothan (24% clay) soil were, on the average, approximately twice as high as those from unlimed Troup (10% clay) soil. Lime significantly reduced 241Am uptake from both soils. The americium concentration ratios (americium concentration in dry plant tissue/average americium concentration in dry soil) for limed treatments were, in general, one order of magnitude lower than those for unlimed treatments. Organic matter, added to the soils as bermuda grass hay, somewhat reduced 241Am uptake, especially when added at high rates in unlimed soils.

The effect of lime on uptake could be attributed to immobilization of americium ions external to the roots as a result of decreased solubility of this radionuclide and/or antagonistic effect of increased calcium ion concentration in the soil solution on americium ions. The effect of organic matter on uptake could be attributed to its fixing capacity for metals.
Adherence of Spray‐applied Liquid Digested Sewage Sludge to Tall Fescue
Authors: Chaney Rufus L. , Lloyd Cheryl A.
Published: July 2010

Liquid anaerobically digested sewage sludge was spray‐applied on field plots of mowed and unmowed tall rescue (Festuca arundinacea Schreb) at rates of 0, 51, and 103 m3/ha in mid‐September 1975. Forage samples were periodically cut to a 7‐cm height following rainfall events for 80 days, and again the following spring. The concentrations of Fe, Cu, Zn, Pb, Cd, and Ni were markedly increased by sludge spraying, with a greater increase at the higher sludge rate. The levels of Fe, Pb, and Cu in samples of healthy plants were so high (37,800 mg Fe, 140 mg Pb, and 115 mg Cu/kg dry forage) that absorption‐translocation by the roots could not have supplied them. The %‐sludge in/on the forage was calculated for each element based on the proportion of increased metal content in/on the forage to the metal content of the sludge. The %‐sludge estimates for six elements were in close agreement, confirming sludge contamination rather than metal uptake from soil. Adhering sludge was not removed by washing in 0.1% Na lauryl sulfate. Adhering sludge comprised 22 to 32% of the forage on the day of application; sludge content decreased with time but was not related to rainfall events (27 cm during 15 days following sludge application). Sludge content declined more rapidly in the mowed treatment, apparently because less forage was contaminated and rapid growth diluted contaminated forage. Sludge was no longer found in/on forage samples grown after spring mowing. Adhering sludge could increase exposure of forage consumers to heavy metals and other sludge constituents.
Sorption of a Dispersed Dye by Sand and Soil
Authors: Miyamoto S. , Tram J.
Published: July 2010

The sorption of monoazo dye (a dispersed dye) by sand and calcareous soil is evaluated by laboratory batch and column tests for the purpose of obtaining quantative information needed for disposing of dyeing effluent. In the batch tests, the soil samples were added to dye solutions (or dispersions) having a concentration range of 25 to 125 mg/liter. During the continuous shaking of the solutions, the amount sorbed was measured up to 18 hours. Results indicated that sand and soil sorb the dye and that the reaction is essentially complete within 3 hours. The sorption isotherm was well represented by the Langmuir equation with sorption capacities of 2.6 and 15.1 mg/g for sand and loam, respectively. Subsequent column tests indicated that a sand or soil bed can decolorize the dye solution. The mass transfer equation, considering the sorption and the convective transfer factors, simulates reasonably well the breakthrough curve in sand, but only if an adjustment is made for the reaction rate constant. A filtration mechanism appears to play a significant role in dye removal, especially in a soil bed having fine pore spaces. The sorption data obtained here are relevant to the evaluation of potential ground water contamination resulting from land disposal of dyeing effluent, as well as to the use of a sand bed for decolorization.