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Predatory birds, pesticides, and pollution
1982
Cooke, A. S. | Bell, A. A. | Haas, M. B.
Reactions of chrome tannery sludge with organic and mineral soils
1982
Wickliff, C. (US Environmental Protection Agency, Corvallis, Oregon (USA). Corvallis Environmental Research Lab.) | Volk, V.V. | Tingey, D.T. | Griffis, W.L. | Trunk, M.Y. | Witherow, J.L.
Chrome tannery sludge applied to agricultural land may have benefits in terms of added N for crop growth. An experiment was designed to compare tannery waste with commercial N fertilizer and investigate the potential of the waste as an alternative or supplement to commercial fertilizer. Soils with 38% and 7% orggganic C and N content of 1.3% and 0.2% respectively, were amended with lime, commercial N fertilizer, or tannery sludge containing 1.6% Cr. A portion of the tannery waste was supplemented with additional Cr('3+) salt before adding to the soils. The amended soils were analyzed for total Cr, ammonium acetate extractable Cr, selected nutrient and trace element concentrations. The tannery sludge increased soil pH, total Cr and N, S, Ca, P, Mg, and Na concentrations. DTPA extractable Cr increased only when Cr('3+) salt was added, but soil pH decreased markedly. Electroconductivity of the soils increased with the waste application rate and, at the highest rate of Cr('3+) salt addition, far exceeded values recommended for successful crop production. The acidic, high salt conditions complicated interpretation of the Cr('3+) salt addition results. Tannery sludge may be applied to agricultural land as a fertilizer amendment without adversely affecting soil chemical properties. The amount and frequency of application should be determined by (1) total and available N, (2) total salt content, (3) total and available Cr, and (4) soil organic matter.
Mostrar más [+] Menos [-]Changes to a soil on irrigation with a sanitary landfill leachate
1982
Chan, K.Y. (State Pollution Control Commissions, Lidcombe, NSW (Australia))
A detailed soil column leaching experiment was set up to investigate the changes in properties to a soil as a result of irrigation with an alkaline sanitary landfill leachate (pH 10.3). Chemistry of the soil was drastically altered as a consequence of the interaction. The soil was titrated from pH 5 to pH 10 and was changed from an exchangeable Mg dominated soil to an exchangeable Ca dominated soil. Magnesium was displaced by ion exchange reaction at acid pH, but at pH 10, 14.2 meq 100/g of Mg, i.e. up to three times the cation exchange capacity of Mg, was adsorbed in non-exchangeable forms at the immediate surface of the soil column by specific adsorption reactions. The leachate-treated soil was not stable on distilled water leaching. Structural breakdown led to clay dispersion and reduction in pore space, resulting in a 64 times reduction in hydraulic conductivity, 1.6 x 10('-4) to 2.5 x 10('-6) cm/s. The structural breakdown could be explained in term of the increase in Na adsorption ratio of the treated soil and the subsequent reduction in electrolyte concentration following the distilled water treatment.
Mostrar más [+] Menos [-]Effect of heavy metals on microorganisms in soils near secondary lead smelter
1982
Bisessar, S. (Ontario Ministry of the Environment, Toronto (Canada). Phytotoxicology Section)
Soil samples were collected to a depth of 0 to 10 cm from several sites near a secondary Pb smelter during the summer of 1976 in order to determine heavy metal concentrations of soil and enumerate soil microorganisms and earthworms. Chemical analyses indicated that abnormally high concentrations of Pb, As, Cd, and Cu decreased with increasing distance from the source and population counts of bacteria, actinomyces, fungi, nematodes and earthworms increased with increasing distance from the smelter. The negative correlation coefficients between bacteria, actinomyces, fungi, and nematodes and the level of Pb, As, Cd, and Cu in the soil were statistically significant. The microflora of the contaminated soil was altered and the marked quantitative reduction or elimination of organisms were attributable to heavy metal pollution emission from the secondary Pb smelter.
Mostrar más [+] Menos [-]Occurrence and distribution of chemical pollutants in Lake Mariut, Egypt, 1: residues of organochlorine pesticides
1982
Saad, M.A.H. (Alexandria Univ. (Egypt). Oceanographic Dept.) | Abu Elamayem, M.M. | El-Sebae, A.H. | Sharaf, I.F.
Occurrence and distribution of organochlorine pesticides in the water of Lake Mariut, a brackish coastal Egyptian lake suffering from pollution, and their accumulation in the common fish Tilapia were studied. The major pesticides detected in the lake water were lindane, p, p'-DDE, o, p'-DDT, and p, p'-DDT. These compounds, except o, p'-DDT, were detected in the fish samples in exceedingly higher concentrations compared with those found in the lake water.
Mostrar más [+] Menos [-]Fecal coliform densities in a western watershed [irrigation, river basin, Colorado]
1982
Psaris, P.J. (Black and Veatch, Denver, Col. (USA)) | Hendricks, D.W.
This paper describes the areal distribution of fecal coliform densities within the stream system of the South Platte River basin in Colorado. Low densities, e.g., 0 to 99 fecal coliforms per 100 ml, were found in mountain streams, while higher densities, e.g., 10000 to 100000 and above were found in plains streams. About 49% of the plains stations and 3% of the mountain stations were not in compliance with the Colorado secondary contact recreation standard of 2000 fecal coliforms per 100 ml. The higher fecal coliform densities were associated with discharges from wastewater treatment plants. This is significant from a public health standpoint since the tainted waters are spread throughout the South Platte basin to irrigated lands via streams, canals, and reservoirs. Because of current federal and state policy encouraging land treatment and reuse, such practice should be reviewed with respect to compliance with proposed fecal coliform standards, and whether such standards should be adopted.
Mostrar más [+] Menos [-]Oxidant effects on forest tree seedling growth in the Appalachian Mountains [USA]
1982
Duchelle, S.F. | Skelly, J.M. | Chevone, B.I. (Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (USA). Dept. of Plant Pathology and Physiology)
Long range transport of episodic concentrationns of 0(,3) into the Appalachian Mountains of Virginia was recorded in the summer season of 1979 and 1980. Continuous monitoring of 0(,3) indicated monthly averages of 0.05 ppm 0(,3) and several periods averaged approx. 0.08 ppm 0(,3). Open-top chambers were used to test the effect of ambient doses of the pollutant on the growth of 8 planted forest tree species native to the area. Height growth was suppressed for all species at the end of the second growing season when grown in open plots (no chamber) and ambient chambers compared to those grown in charcoal-filtered air supplies chambers. Height growth trends of open ambient chamber filtered air chamber were consistent. Virginia pine and green ash were significantly taller (p
Mostrar más [+] Menos [-]Potential effects of acid precipitation on soil nitrogen and productivity of forest ecosystems
1982
Aber, J.D. (Wisconsin Univ., Madison (USA). Dept. of Forestry) | Hendrey, G.R. | Botkin, D.B. | Francis, A.J. | Melillo, J.M.
Numerous field and laboratory studies have shown measurable effects of soil acidification on soil processes and yet there is no indication to date that forest production is being affected even in heavily impacted areas. A discussion of possible reasons for this apparent contradiction is presented along with results of two computer simulations of possible responses to acid rain induced changes in (a) N availability and (b) soil organic matter decomposition rate. The first simulation shows a direct relationship between N availability and forest production. The second indicates the possibility for a more complex response with changes in total soil organic matter more than compensating for changes in decomposition rate and producing an inverse relationship between decomposition rate and N availability.
Mostrar más [+] Menos [-]Liming of acidified lakes: induced long-term changes [Sweden]
1982
Hultberg, H. | Andersson, I.B. (Swedish Water and Air Pollution Research Inst., Goeteborg (Sweden))
This study presents data concerning long-term trends after neutralization of four acidified lakes in two regions on the Swedish west coast. Neutralization was achieved by a di-Ca-silicate with 52% CaO and about 11.5% MgO. Between 61 and 74% of the spread lime product dissolved during a 5 to 7 yr period. The liming increased pH, from a range of 4.5 to 5.2 to near neutral and restored alkalinity in the range of 0.2 to 0.3 meq/l and the Ca-content became 3 to 4 times higher than before liming. In two lakes transparency decreased significantly presumably due to changed phytoplankton composition. These changes successively declined due to dilution and continuous acid loading. The changes in water chemistry and development of stocked brown trout (Salmo trutta) populations initiated biotic changes. Phyto- and zooplankton communities reacted both instantly and later with successions in species composition. Changes of benthic macroinvertebrate species occurred over several years, but some pelagic species, e.g. corixids were rapidly reduced due to predation of fish. Observed changes were predominantly due to expanding populations of species present at very low abundances even during acid state of the lakes. Some organisms found during preacid state of the lakes did not establish new populations and this process may need a prolonged time with favourable conditions. Reacidification towards the end of the study period significantly stressed the brown trout population and also favoured expansion of the filamentous alga Mougeotia sp. and Sphagnum sp. that almost vanished during the first year after liming. Decreasing concentration of total P was not influenced by neutralization and may be mostly dependent on negative changes in the soils surrounding the lakes. If generally valid, this process may be an important factor for the oligotrophication of lakes in areas where acid deposition is high.
Mostrar más [+] Menos [-]The effect of pH and calcium on fish and fisheries
1982
Brown, D.J.A. (CERL Freshwater Biology Unit, Nottingham (UK). Midlands Region Scientific Services Dept.)
The combined effect of Ca and pH on fish and fisheries is considered for both laboratory and field studies. It can be seen that at concentrations less than 100 mu-eq/l, Ca can exert a significant influence on survival times of fish, and similarly in the field, the number of fishless lakes and the number of fish species found in lakes are less dependent on H('+) concentration at low concentrations of Ca than at high Ca levels. The limited historical field data available suggest that alongside any increase there may have been in surface water acidity, Ca concentrations have also increased, and the latter may have offset to some extent the deleterious biological effects of this increased acidity. Nevertheless, details of seasonal and spatial variations in these important water quality factors will need to be considered before a full understanding of the response to acidity of a fishery can be reached.
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