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Environmental factors influencing the rate of spread of the grass Deschampsia cespitosa invading areas around the Sudbury [Canada] nickel-copper smelters
1981
Cox, R.M. | Hutchinson, T.C. (Toronto Univ., Ont. (Canada). Dept. of Botany and Inst. for Environmental Studies)
A study has been made of the soil chemistry and atmospheric quality of 9 Sudbury area sites where populations of Deschampsia cespitosa have invaded the contaminated industrial barrens near the smelters since 1972. The rate of increase in cover within marked quadrats was greater at sites near the disused Coniston smelter than at sites near the two active smelters. Air quality monitoring, using bulk collectors and sulphation plates, indicated substantial drops in phytotoxic air pollutants during the 1978-79 smelter shutdowns. Surface loadings of various metals were evident in soil at sites near the active smelters, whereas this was no longer true at sites near the Coniston smelter disused since 1972. However, water extractable levels of Ni and Cu at these sites remained as high as those found near the active smelters which also have high extractable soil Al. Both comparative studies and multiple regression analysis indicate that the rate of increase in cover of D. cespitosa in the populations studied correlate best with particulate deposition of Cu and Ni followed by sulphation rate and then by soil extractable Al. These findings are discussed in relation to tolerances of local populations, as well as to the potential effects of airborne particulates on growth
Показать больше [+] Меньше [-]Trace element concentrations in tropical marine fish at Bougainville Island, Papua New Guinea
1981
Powell, J.H. (Bougainville Copper Limited, Panguna, Bougainville Island (Papua New Guinea). Environment Dept.) | Powell, R.E. | Fielder, D.R.
Baseline trace element concentrations have been measured in 8 species of marine fish from Bougainville Island, Papua New Guinea. This is the first stage in an assessment of environmental impact associated with mining operations. In general, concentrations of Cu, Pb, Zn, Cd, Hg, and As in edible portions of the fish comply with Australian National Health and Medical Research Council public health standards. Two species of shark contained As concentrations in muscle tissue in excess of prescribed standards. Increased concentrations of Cu, Zn and Cd were recorded in liver and kidney, But Hg and Pb were not preferentially accumulated in these organs. The relationship between the size of fish and metal assay was investigated. Mercury content and weight of fish were always positively correlated but concentrations of other metals were variably correlated with size
Показать больше [+] Меньше [-]The role of atmospheric deposition in an eastern U.S. deciduous forest
1981
Lindberg, S.E. (Oak Ridge National Lab., Oak Ridge, TN (USA). Environmental Sciences Div.) | Hariss, R.C.
Atmospheric sources contributed significantly to the annual flux of trace metals and sulfate to the forest floor of Walker Branch Watershed, a forested catchment in the southeastern United States. Atmospheric deposition supplied from 14%(Mn) to approx. 40%(Zn, Cd, SO(,4)('2-)) to 99%(Pb) of the annual flux to the forest floor; the remainder was attributable to internal element cycling. The measured water solubility of these metals in suspended and deposited particles indicates that they may be readily mobilized following deposition. Dry deposition constituted a major fraction of the total annual atmospheric input of Cd and Zn(20%), SO(,4)('2-)(35%), Pb(55%), and Mn(90%); however, wet deposition rates for single events exceeded dry deposition rates by one to four orders of magnitude. Interception of rain by the canopy resulted in loss of Cd, Mn, Pb, Zn, and SO(,4)('2-) from the canopy, but uptake of H('+) which increased with increasing free acidity of the incoming rain, and with increasing residence time of the rain on the leaf surface
Показать больше [+] Меньше [-]Pesticide disposal and detoxification: processes and techniques.
1981
Dillon A. P.
[Industrial molybdenosis in bovines]
1981
Parada, R. (Universidad de Chile, Santiago. Facultad de Ciencias Agrarias, Veterinarias y Forestales. Dept. de Patologia)
[Environmental health activities of the Ministry of Health [Chile]]
1981
Corey, G. (Ministerio de Salud, Santiago (Chile))
[Use of herbicides and environmental pollution]
1981
Kogan A, M. (Universidad de Chile, Santiago. Facultad de Ciencias Agrarias, Veterinarias y Forestales)
[A case of air pollution and its incidence on natural environment]
1981
Rodriguez R, O.
Indicators of pollution by lead in Santiago [Chile]
1981
Cisternas, R.E. (Pontificia Universidad Catolica de Chile, Santiago)
Quantitative studies on the presence of organophosphorus compounds in rats
1981
Grumberg N, J. | Capurro S, L. | Ipinza R, J.