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Sulphur and nitrogen nutrition and misting effects on the response of bluegrass to ozone, sulphur dioxide, nitrogen dioxide or their mixture
1981
Elkiey, T. | Ormrod, D.P. (Guelph Univ., Ontario (Canada). Dept. of Horticultural Science)
Kentucky bluegrass (Poa pratensis L.) plants, cultivars Cheri, Merion and Touchdown were grown at complete nutrition or with low S or low N. Plants were exposed to 10 ppm (v/v) O(,3) for 6 h/d, 15 pphm SO(,2) continuously, 15 pphm NO(,2) continuously, or their mixture at these concentrations for 10 days. The severity of injury was much increased by misting with deionized water for 5 min twice daily, especially with SO(,2) and NO(,2) single gas exposures. The misting did not have consistent effects on total S, total N, leaf area or fresh weight. Exposure to O (,3) decreased leaf area without affecting S or N content, while SO(,2) usually increased total S and, in some cases, increased total N. Exposure to NO(,2) increased total N without affecting total S, and the mixture increased both total S and total N. Low S or low N usually enhanced the effect of SO(,2) or NO(,2), respectively. Leaf area and fresh weight were not as responsive to the treatments as total S and total N. Rainfall outdoors may be a major meteorological factor affecting plant injury response to gaseous pollutants
Afficher plus [+] Moins [-]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
Afficher plus [+] Moins [-]Effects of SO2 exposure on carbohydrate contents, phytomass and caloric values of wheat plants
1981
Prasad, B.J. | Rao, D.N. (Banaras Hindu Univ., Varanasi (India). Centre of Advanced Study in Botany, Lab. of Ecology)
This paper reports the results of wheat plants exposed to SO(,2). The SO(,2)-treated and control plant samples were periodically analyzed with respect to their carbohydrate content, caloric values, phytomass accumulations and net primary productivity. An initial increase, but later decrease in all these parameters was recorded in SO(,2)-treated plants. These effects in wheat plants have been interpreted in terms of energy budget of plants under SO(,2)-stress condition.
Afficher plus [+] Moins [-]Species and ecosystem level bioindicators of airborne pollution: an analysis of two major studies [Pinus, Agropyron, deer, Montana, Poland]
1981
Grodzinski, W. (Natural Resource Ecol. Lab., Colorado State Univ., Fort Collins, CO 80523 (USA)) | Yorks, T.P.
Groundwater quality in Visakhapatnam Basin, India
1981
Sarma, V.V.J. | Swamy, A.N. (Andhra Univ., Waltair (India). Dept. of Geophysics)
Visakhapatnam Basin, located on the east coast of India adjoining the Bay of Bengal, is surrounded by hills. Groundwater in the basin is utilized for domestic, irrigational, and industrial purposes. The basin measures about 148 km('2) in which 35% of the land is utilized for irrigation, and 10% of the land for industries. However there is a rapid industrial development in the basin along with increasing population initiating the necessity to evaluate groundwater resources. The chemical quality of groundwaters available in the basin is discussed in relation to domestic, irrigational, and industrial purposes.
Afficher plus [+] Moins [-]Effect of pentachlorophenol on asymbiotic nitrogen fixation in soil
1981
Tam, T.Y. | Trevors, J.T. (Waterloo Univ., Ont. (Canada))
The effect of 50, 100, 150, and 400 mu-g sodium pentachlorophenate (Na-PCP) per gram soil was studied in nonsterile soil incubated under aerobic and anerobic conditions, and in sterilized soil inoculated with Azotobacter sp. isolated from the soil. N(,2) fixation was determined by acetylene reduction. Pentachlorophenate at a concentration of 50 mu-g/g had an inhibitory effect in nonsterile soil incubated aerobically while strong inhibition of dinitrogen fixation in nonsterile soil occurred in the presence of 100 mu-g/g and above. The EC(,50) values for the inhibition of nitrogenase activity in nonsterile soil incubated aerobically and anaerobically and in sterlilized soil inoculated with Azotobacter sp. suspensions were 49.8 +/- 1.4 mu-g Na-PCP/g, 186.8 +/- 2.8 mu-g Na-PCP/g, and 660.8 +/- 29.3 mu-g Na-PCP/g, respectively.
Afficher plus [+] Moins [-]Aquatic pollution
1981
Laws, Edward A.
New York : Wiley, 1981.
Afficher plus [+] Moins [-]Pesticide disposal and detoxification: processes and techniques.
1981
Dillon A. P.
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
Afficher plus [+] Moins [-]Occurrence and distribution of chemical pollutants in Lake Mariut, Egypt, 2: heavy metals, [(Tilapia fish)]
1981
Saad, M.A.H. | Ezzat, A.A. | El-Rayis, O.A. | Hafez, H. (Alexandria Univ. (Egypt). Faculty of Science, Oceanography Dept.)
The occurrence and distribution of heavy metals in the water of Lake Mariut, a heavily polluted brackish water lake in Egypt, and their accumulation in the different parts of Tilapia fish in this lake were studied. The variations in concentrations of the metals (Zn, Cu, Fe, Mn and Cd) in the lake water are mostly due to variations in the discharge rate of dumped wastes. The mean concentrations of these metals in different fish parts were much higher than those in the lake water.
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