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Short-term effects of oil pollution on species numbers and productivity of a simple terrestrial ecosystem [grassland]
1981
Kinako, P.D.S. (Port Harcourt Univ. (Nigeria). School of Biological Science)
Irradiated digested sewage sludge: effects on plant-symbiont associations in the field [bean, onion]
1981
Spitko, R.A. (Massachusetts University, Amherst, 01003 (USA)) | Manning, W.J.
Nitrogen and land reclamation [including role of legumes]
1981
Lanning, S. (Dep. of Bot., Liverpool Univ., Liverpool L69 3BX (UK)) | Williams, S.T.
Changes in the soluble protein content of soybean Glycine max L. and pea Pisum sativum L. under continuous SO2 and soot pollution
1981
Sardi, K. (Dep. of Bot. and Pl. Physiol., Keszthely Agric. Univ., Keszthely (Hungary))
Species and ecosystem level bioindicators of airborne pollution: an analysis of two major studies
1981
Grodzinski, W. (Jagiellonian Univ., Krakow (Poland). Dept. of Animal Ecology) | Yorks, T.P. (Colorado State Univ., Fort Collins, CO (USA). Natural Resource Ecology Lab.)
Bioindication of air pollution effects has received considerable attention in recent years. It has been almost entirely focused on individual species and relatively little notice has been given to ecosystem level process and function monitors. Longterm research projects in the Niepolomice Forest in southern Poland and the Colstrip area in southeast Montana, U.S.A., were analyzed for both organismic and system level indicators and monitors for SO, trace elements, and fluoride pollution originating in nearby coal-fired industrial processes. Species of lichens exhibited changes in morphology and survival and pine species exhibited pollutant accumulation in needles at both sites. Declines in Scots pine growth in Poland of up to 20% were compared with declines in western wheatgrass rhizome biomass in Montana to illustrate system wide effects on primary productivity. Directly observable declines in decomposition rate were noted for both sites at higher pollution levels and tied to system wide occurrences of nutrient deficiency and toxicant buildup in soil pools. Pollutant increases in deer antler composition, changes in grasshopper dietary patterns, and lichen density and health were postulated to have system level implications as well
Show more [+] Less [-]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.
Show more [+] Less [-]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.
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.
Show more [+] Less [-]Leaching of metals from the A-horizon of a spruce forest soil
1981
Tyler, G. (Lund Univ. (Sweden). Dept. of Plant Ecology)
The study quantifies the amount of metals, (Na, K, Mg, Ca, Al, Fe, Mn, Ni, Cr, V, Cu, Zn, Cd, Pb) leached from the A-horizon of a podzolic spruce forest soil in southern Sweden during 2.5 yr, and offers statistical evidence of environmental conditions of importance to metal release. Considerable losses of Pb, Cr, Ni and V may occur from the A-horizon of forest soils under conditions favoring leaching of organic matter, Fe, and Al, i.e. during periods of comparably high soil temperature and moisture. Metals with a larger fraction present in exchangeable form (Na, Mg, Ca, Zn, Cd) are more susceptible to minor pH changes. An accelerated deposition or internal production of acidic matter therefore will reduce the retention times of these elements particularly.
Show more [+] Less [-]Atrazine residues in estuarine water and the aerial deposition of atrazine into Rhode River, Maryland [USA]
1981
Wu, T.L. (Smithsonian Institution, Edgewater, MD (USA). Chesapeake Bay Center for Environmental Studies)
Water samples from the Rhode River, an estuary situated on the western shore of the Chesapeake Bay, were analyzed for atrazine residues twice a week for 2 yr. Precipitation samples, which included dryfall, rainfall, and snowfall were collected with wide-mouth stainless steel collection pans situated about 20 m above ground in an open space. A total of 68 precipitation samples was collected from December 1976 to February 1979. Atrazine residues were detectable in estuarine water and in rainwater year-round. Atrazine residues in estuarine water were generally 6 to 190ng/l, atrazine residues in rainwater (bulk precipitation) were 3 to 2190ng/l. Atrazine residues in rainwater samples collected during the winter season (January to April 1977) were unexpectedly high (e.g. 3 to 970ng/l). The highest atrazine concentration of 2190ng/l was detected from a 0.76 cm rainfall event collected on May 19, 1977. Intermittent spraying operations of atrazine within the cornfields were generally done during May of each year. Rain samples collected during May of 1978 also showed higher atrazine residues than the rest of the 1978 growing season, but at levels much less than those detected in 1977 rainwater. Although high attrazine concentrations were detected in winter rainfall, these did not result in similarly higher atrazine concentrations in estuarine receiving waters. Our data showed a decline of atrazine concentrations in estuarine water in October and November which continued until a rainfall following Spring herbicide applications. Atrazine is enriched at the microsurface layer of estuarine water, but direct atmospheric input of atrazine did not seem to contribute significantly to the enrichment mechanism. Atrazine is believed to be transported long distances in polluted air masses. The estuarine microsurface layer could be a source of atmospheric atrazine, but the importance of the source is yet to be determined. Atrazine was quantitatively determined by GC using a nitrogen specific electrolytic detector and was confirmed by GC/Mass.
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