Showing papers in "Journal of Environmental Quality in 1978"

The Pesticide Content of Surface Water Draining from Agricultural Fields—A Review

Abstract: The literature on pesticide losses in runoff waters from agricultural fields is reviewed. For the majority of commercial pesticides, total losses are 0.5%0 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.

Soil Organisms as Components of Ecosystems

Abstract: This book is the Proceedings of the 6th International Soil Zoology Colloquium held in Uppsala in June 1976. The major theme is the interactions of plant roots, microorganisms, and soil animals. Four subthemes were chosen for the plenary sessions. These were: (i) Community structure and niche separation; (ii) The role of soil organisms in nutrient cycling; (iii) Plant roots in the soil system; and (iv) Models of soil organisms and their environment. In addition tothe 51 papers (14, 16, 13, and 8) presented in the above sessions, there are summarized versions of 41 papers given in poster session. The individual papers range from excellent to poor, with about one-fourth in the poor category. About half the remainder are autecological in subject matter treatment and lack the perspective promised in the colloquium title. Most of the papers in the first plenary session are on niche exploitation and responses by members of the soil fauna rather than on their roles as ecosystem components. The papers on nutrient cycling are, with few exceptions, excellent contributions. Particularly commendable is the comprehensive discussion offered by D. E. Reichle. The bulk of the papers in the third session concern either the activities or the effects on plants of rhizophagic invertebrates. Good discussions are given by Vancura and associates on quantitative aspects of root exudation and by Sihanonth and Todd on transfer of nutrients by ectomycorrhizal fungi. Readers expecting to find any noteworthy array of simulation models on soil organisms will be disappointed. Most of the papers in this session might have been placed just as appropriately in some other session. The closing session address by J. E. Satchell is thought-provoking as well asentertaining. The reader, while being told that earthworms are the trombones of the grave, gains the impression that as a group, the soil zoologists are alive and well. Mechanistically the book is soft cover and generally excellently edited. There are about 200 illustrations, mostly line graphs and histograms, but also some light microscope and scanning electron micrographs. Unfortunately, some of the hand-drawn diagrams are so overcrowded with small-scale details as to be practically unreadable. This volume belongs primarily in the personal libraries of invertebrate zoologists. Its reading by systems ecologists and soil scientists will be, in part, time well spent.--FRANCIS E. CLARK, Federal Research, Western Region, U.S. Department of Agriculture, P.O. Box E, Fort Collins, CO 80522.

Nitrate Accumulation in Soils and Loss in Tile Drainage Following Nitrogen Applications to Continuous Corn

Abstract: Nitrate-N concentration in tile water, loss from tile lines, and accumulation in soil profiles were determined following each of three annual applications of 20, 112, 224, and 448 kg N/ha to continuous corn (Zea mays L.) grown on a Webster clay loam (Typic Haplaquoll) in southern Minnesota. Plots were isolated to a depth of 1.8 m with plastic to allow an accurate assessment of the area drained. Water flow through the tile lines occurred annually for approximately 6 weeks in the period from mid-April through early July and constituted an equivalent from 20 to 46% of the precipitation during the flow periods and from 7 to 22% of the annual precipitation during the 3 years studied. There was relatively little increased NO₃-N accumulation in the soil profile or loss from tile lines at the recommended application rate of 112 kg N/ha compared to that for the check treatment. Nitrate-N losses through tile lines in 1975 (after 3 years treatment) were 19, 25, 59, and 120 kg/ha for the 20, 112, 224, and 448 kg N/ha applications, respectively, which had NO₃-N accumulations in the 0–3 m soil profiles of 54, 100, 426, and 770 kg NO₃-N/ha. Maximum NO₃-N accumulation in the soil profiles occurred at a depth of about 1 m with little evidence of movement below about 2.2 m.

Ammonia Volatilization from Sewage Sludge Applied in the Field

Abstract: Volatilization of ammoniacal nitrogen from newly applied anaerobically digested sewage sludge was measured in the field using an aerodynamic method in May and Oct. for 5- and 7-day periods, respectively. Sludge was applied in a circular area of 0.405 ha at rates of 116,480 kg/ha (150 kg NH₄⁺-N/ha) and 134,400 kg/ha (89 kg NH₄⁺-N/ha) in the May and Oct. experiments, respectively. Windspeed and atmospheric ammoniacal N was measured at 10, 50, 100, and 150 cm above the soil surface providing time averaged vertical profiles at the center of the area from which ammoniacal N flux was estimated. Flux was determined on the premise that NH₃ molecules leaving a horizontal surface must be carried through a vertical plane by horizontal air flow. Fluxes generally followed a diurnal pattern with maximums occurring at about midday. Flux generally decreased with time in an exponential manner. Thus, the “half life” of ammoniacal N applied in the sludge was 3.6 and 5.0 days for the May and Oct. experimental periods, respectively. Of several meteorological variables measured, air temperature appeared to be most closely related to flux rate especially in the two or three days following application. It was estimated that, during the 5-day experimental period in May, 60% of the 150 kg ammoniacal N/ha applied in sludge was volatilized. During the 7-day experimental period in Oct. 56% of the 89 kg ammoniacal N/ha applied was volatilized. Sampling the sludge layer and soil beneath it during and after the Oct. experimental period resulted in considerable variability in ammoniacal N estimates and, hence, in volatilization estimates.

Influence of pH, Phosphorus, Cadmium, Sewage Sludge, and Incubation Time on the Solubility and Plant Uptake of Cadmium

Abstract: Corn (Zea mays L.) ‘Pioneer-3932A’ was grown in the greenhouse on a loamy sand amended with cadmium, cadmium-spiked sewage sludge, and sewage sludge. Soil pH was adjusted to approximately 5.7, 6.7, and 7.8, and phosphorus was applied at 0, 200, and 400 µg/g soil. Soil treatments were applied 0, 8, and 16 weeks prior to planting, and the plants were grown for 5 weeks. Increasing the pH of the soil amended with inorganic cadmium (CdSO₄) decreased the Cd concentration of corn seedlings by approximately 67%. The Cd concentration was reduced approximately 47% for a similar increase in pH on soil amended with Cd-spiked sludge. The Cd concentration of corn seedlings was significantly reduced by the addition of P. Increasing incubation time decreased the availability of added inorganic Cd, but increased the availability of Cd applied with sewage sludge. Increasing the amount of Cd added to the soils increased the Cd concentration of the corn seedlings regardless of the form of Cd used. Cadmium concentrations in the corn seedlings were significantly correlated with DTPA-extractable soil Cd. Solubility measurements of Cd in the acidified soils showed undersaturation with respect to all known Cd minerals, whereas in soils above pH 7.25 the Cd solubility was limited by CdCO₃ at a CO₂ level of 0.003 atm or higher and showed the expected hundredfold decrease in solubility for each unit increase in pH. The minerals Cd₃(PO₄)₂ and Cd(OH)₂ are much too soluble to account for the precipitation of Cd in these soils.

Virus Adsorption by Five Soils

Abstract: Four of five soils studied adsorbed the bacteriophage φX-174 in accordance with the Freundlich isotherm The soil not adsorbing viruses was the coarsest textured and had the highest pH For purposes of comparing rates in kinetic studies, this soil was considered to have a zero adsorption rate The amount of virus adsorbed was linearly related to the square root of time When adsorption rates for the soils were plotted against cation exchange capacities, specific surface areas, and organic matter contents, fair correlation was found for four of the soils The lack of correlation for the one soil may have been due to its high organic matter content blocking virus adsorption The rates of adsorption determined from square root of time plots were significantly correlated with soil pH at the 1% level (r = −094), indicating the importance of the influence of pH on virus charge

Survival and Movement of Fecal Indicator Bacteria in Soil under Conditions of Saturated Flow

Abstract: Antibiotic-resistant fecal bacteria were used to monitor the degree of movement and subsequent ground water contamination by septictank effluent discharged into a drainfield under saturated conditions. Two pits of different depths were constructed to simulate drainfield beds, and ground water samples were removed during 32-day sampling intervals from sampling wells installed at set distances from each inoculation pit. The bacteria added to the deep pit were released into a B2t horizon which contained a higher clay content than the A horizon in which the shallower pit was installed. Streptomycin-resistant strains of Escherichia coli and Streptococcusfaecalis amended to each pit site moved in a directional manner, required more time to reach sampling wells when inoculated into the deeper of the two pits, and moved relatively long distances when considering that the area where the sites were located had only a 2o70 slope. Bacterial numbers peaked in the sampling wells in association with major rainfall patterns and the populations required longer periods to peak in the wells furthest from the inoculation pits. The results indicated that antibiotic-resistant bacteria eliminated the problem of differentiating between the amended bacteria and those nonresistant strains already in the soil, and the potential is excellent for including this type of microbiological procedure for assessing the suitability of a soil site for septic-tank and waste water drainfield installations.

Stream chemistry and watershed nutrient economy following wildfire and fertilization in eastern Washington

Abstract: During the first 3 years after a severe wildfire in 1970, maximum concentrations of nitrate-N (NO/sub 3/-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 NO/sub 3/-N concentration in the stream from an unburned watershed was 0.066 mg/liter. Since NO/sub 3/-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 wre 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 rom 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).

Metal Distribution in Forested Ecosystems in Urban and Rural Northwestern Indiana

Abstract: Metal distribution in vegetation and soil components, annual inputs, and losses were determined in undisturbed urban and rural ecosystems in northwestern Indiana The urban area has been exposed to contamination from industrial and other urban sources for about 100 years The levels of cadmium, zinc, copper, and lead were significantly higher in the soils and vegetation on the urban site compared to a similar system in a rural setting 67 km away Metal concentration in the top 25 cm of soil averaged 10 ppm Cd, 2456 ppm Zn, 463 ppm Pb, and 119 ppm Cu This was 20 to 100 times more concentrated than that found on the rural site The surface litter (O horizon) on the urban site also had four to nine times greater metal concentration and metal quantities were many times greater in the urban ecosystem than on the rural site The higher soil levels were reflected in higher concentrations in most plant species, but species differed greatly in metal levels Greater than 95% of the weight of all four metals was found in the soil (0-25 cm) for both dune and wetland ecosystems The remaining metal burden is equally distributed between the surface litter and themore » plant biomass Slightly more Cd and twice as much Zn entered the urban site than the rural site during 1975-76 Annual input of Pb and Cu was four times greater on the urban site While pollution control has apparently reduced annual input to the urban site, metal concentrations will remain high due to the low rates of leaching losses measured 24 references, 2 figures, 3 tables« less

Seasonal Runoff Losses of Nitrogen and Phosphorus from Missouri Valley Loess Watersheds

Abstract: N/ha) was 39.64 and 3.04 ka/ha, resuectively. About Seasonal losses of nitrogen and phosphorus in surface runoff were determined for a 7-year period from three con-cropped watersheds in southwestern Iowa. Three seasonal periods were defined: fertilizer, seedbed, and establhment period from April through June (PI); reproduction and maturation period from July through November (PZ); and residue period from December through March (P3). Most of the average annual total N and P losses were associated with the sediment portion of runoff and occurred during Pl. The extreme susceptibility of the loess s o b to erosion during P1 must be taken into account when designing consenation practices to control plant nutrient losses. Seasonal discharges of runoff, sediment, and nutrients were much lower from a level-terraced watershed than from two contour-farmed watersheds, which demonstrates the benefit of terracing in resource coasenation. Average annual soluble N and P losses were quite low and never exceeded 1% of the annual fertilizer application. These losses were the highest during P3 from the contour-farmed watersheds. Water and sediment weighted nutrient concentrations were the highest from the contour-farmed watersheds during P3, when residues covered the soil surface. Leaching of soluble nutrients from the residue and the greater selectivity of the soil erosion process for the finer fractions of the soil (i.e., clay and organic material) during snowmelt runoff are probably the factors responsible. Additional I n d u Words: water quality, nutrient loss, surface run-

Infectious Disease Hazards of Landspreading Sewage Wastes

Abstract: Major increases are currently taking place in the United States in the application of sewage wastes to agricultural land. This paper reviews literature relating to the question of whether such applications involve hazard from human disease organisms. Evidence on the matter is still inadequate. Processed sewage wastes often contain residual pathogenic viruses, bacteria, cysts of protozoa, and ova of helminths, but most sewage-related disease outbreaks have been attributed to use of raw sewage waste water, raw sludges, or night soils on food crops consumed raw, to contamination of drinking water from septic tanks, or to consumption of raw shellfish from sewage-polluted waters. Although subject to relatively high levels of exposure to pathogens in aerosols, waste water treatment plant workers appear to be unaffected, but data on this are limited. Percolation of waste water at a moderate rate through soils of medium to fine texture removes most bacteria and viruses; pathogen movement in surface runoff water may present a greater hazard for spreading disease. Techniques that completely disinfect sludges may fail to stabilize them so that putrefaction is a problem. Properly conducted composting stabilizes raw sludge and destroys most pathogens. Certain fungi and actinomycetes generated during composting may have allergenic potentialities of import for workers at sludge composting sites.

Extractability of Cadmium, Copper, Nickel, and Zinc by Double Acid Versus DTPA and Plant Content at Excessive Soil Levels

Abstract: Cadmium, copper, nickel, and zinc were applied as sulfate salts to samples of surface horizons of three Maryland soils in the greenhouse at rates of metals equivalent to those in 0 to 896 dry metric tons/ha of Washington, D.C., digested sewage sludge. The sludge was also applied at a rate of 224 dry metric tons/ha. Two pH regimes, approximately 5.5 and 6.5, were maintained. Metals were extracted by the DTPA (diethylenetriaminepentaacetic acid buffered at pH 7.3) double acid (0.05N HCl, 0.025N H₂SO₄) extractants. Correlations were determined between extractable soil metals and metal content of two crops of corn (Zea mays L.) each grown for 30 days, but at times of 1 or 13 mo after making the chemical amendments to the soils. Highly significant associations, r values ranging from 0.658 to 0.998, were obtained between the quantities of Cd, Cu, Ni, and Zn extracted by the two extractants. DTPA tended to extract smaller quantities of all metals and tended to be more indicative of reduced plant Zn and Cu uptake under limed conditions than double acid. Cadmium remained the most extractable after 14 mo by either extractant when expressed as a percent of the applied metal that was extractable. Overall metal extractability on this basis followed the order Cd > Cu > Zn > Ni, independent of soil type or extractant. Sludge-applied metals were approximately half as extractable as sulfate salt-applied metals at comparable rates of application, but followed the same order of relative extractability. Plant content ofCd, Cu, and Zn was significantly correlated, at the 1% level, with extractability of the respective metal for both extractants for metal salt-amended soils. Correlations from the sludged soils were poor and generally not significant. Numerically higher and generally more significant correlations were obtained when the data were separated by lime level into two regression equations compared to a combined regression. The primary cause of this effect was the greater metal content of the plant tissue per unit of extractable metal on the low vs. the high pH soils, except for Cd, producing two distinct regression equations. This relationship was more pronounced with the first crop than with the second.

Influence of Cadmium and Zinc on Carbon Dioxide Evolution from Litter and Soil from a Black Oak Forest

Abstract: Studies have shown that heavy metals can reduce decomposition rates. Since litter decomposition is an essential part of forest mineral cycles, understanding the degree of impact that these substances have on such a key process is important. Two similar black oak forests, East Chicago (impacted) and Willow Slough (background), were chosen as study areas. Microcosms containing litter and mineral soil were collected at each site and returned to the laboratory where comparative measurements of carbon dioxide evolution were taken at 0, 12, 36, and 84 hours, and at 23 days. Measurements indicated a higher decomposition rate for the Willow Slough microcosms (138 mg CO/sub 2//hour per kg at 23 days) compared to the East Chicago microcosms (94 mg CO/sub 2//hour per kg). Additional microcosms from Willow Slough were treated with solutions containing all possible combinations of 0, 0.1, or 10 ppM CdCl/sub 2/ and 0, 100, or 1,000 ppM ZnCl/sub 2/. Metal concentrations applied were equivalent to litter and soil levels at East Chicago. Statistically significant differences were detected only 36 hours and 23 days after treatment. Reduced respiration rates were associated with high concentrations of CdCl/sub 2//ZnCl/sub 2/. Suppression of respiration rates due to osmotic effects of metal saltsmore » was rejected after microcosms treated with KCl and CaCl/sub 2/ exhibited no change in respiration. While high levels of cadmium and zinc produced reductions in respiration rates compared to controls, low level treatments may have stimulated decomposition slightly.« less

Precipitation and Throughfall Chemistry in the San Francisco Bay Area

Abstract: 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.

Influence of the Chemical Form of Mercury on its Adsorption and Ability to Leach Through Soils

Abstract: The adsorption of Hg by two soils, differing in chemical and physical characteristics, indicated that both organic Hg compounds (methyl mercuric chloride (MMC) and phenyl mercuric acetate (PMA)) and in organic compounds (mercuric chloride (HgCl/sub 2/)) followed the linear form of the Langmuir adsorption isotherm. The highest adsorption maxima for all Hg compounds were found for the soils which had the higher organic matter content and clay content. Adsorption maxima increased in the order MMC < PMA < HgCl/sub 2/. A two-rate effluent leaching experiment was conducted utilizing undisturbed soil cores of the same two soils and the same three Hg compounds (labeled with /sup 203/Hg) which were applied uniformly to the top 0-10 cm of each column. In contrast to the movement of other cations in the effluent and soil, even at the higher irrigation rate, none of the applied Hg was found to move below the 10- to 20-cm soil layer. More MMC than HgCl/sub 2/ or PMA were found in the 10- to 20-cm layer; however the differences were small. The lack of movement of Hg and the high adsorption maxima was a consequence of the strong binding between Hg compounds and soil. The inability of weakmore » chemical extractants (CaCl/sub 2/, NH/sub 4/OAc, DTPA, EDTA) to remove significant quantities of Hg confirmed this hypothesis. Seven to 31% of the applied Hg was lost from the columns during the experiment presumably by volatilization. 19 references, 2 figures, 4 tables.« less

Availability of sulfur in fly ash to plants

Abstract: Fly ash from a coal-fired power plant was added to soil in variable amounts and the availability of sulfur to a variety of plant species from this source was compared to that of gypsum. The study was conducted under greenhouse conditions with a calcareous and two acid soils which were low in plant-available sulfur. The fly ash used contained 0.4% S, all of which is extractable by NH/sub 4/OAc. When mixed with a calcareous and an acid soil at rates of 1 to 2% by weight, the fly ash corrected a S deficiency in the soil and maximized the yield of alfalfa (Medicago sativa L.) and bermudagrass (Cynodon dactylon L.). The increase in yield (twofold to threefold in alfalfa and 40 to 70% in bermudagrass) was accompanied by an increase in the S content of the plant tops from a deficiency level (<0.1%) to a sufficiency level (greater than or equal to 0.2%). The availability of fly ash-S and gypsum (CaSO/sub 4/ . 2H/sub 2/O)-S was compared by the addition of equal amounts of S from the two sources (25-, 50-, and 100-mg S/kg soil) to an acid soil. Yield and S content of turnip (Brassica rapa L.) and whitemore » clover (Trifolium repens L.) were equally improved, demonstrating that the availability of fly ash derived-S is equivalent to that of gympsum-S.« less