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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.
Show more [+] Less [-]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 [-]Amounts and relative significance of runoff types in the transport of nitrogen into a stream draining an agricultural watershed
1981
Sharpley, A.N. | Syers, J.K. (Massey Univ., Palmerston North (New Zealand). Dept. of Soil Science)
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 [-]Groundwater resources
1981
Mandel, S. (Samuel) | Shiftan, Z. L.
Ozone treatment for industrial wastewater.
1981
Rice R. G. | Browning Myron E.
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.
Show more [+] Less [-]Element mass balances for South Carolina coastal plain watersheds [(USA)]
1981
Gardner, L.R. (South Carolina Univ., Columbia (USA). Dept. of Geology)
Element mass balance estimates for South Carolina Coastal Plain watersheds indicate that fertilizers and liming materials are the major sources for inputs of Ca, Mg, K, Cl, and HCO(,3) whereas precipitation is the major input for Na and SO(,4). Stream flow is the chief mode of output for all of these elements. A balance between input and output is evident only for Cl. Retentions of 50% or more are shown by Ca, Mg, K, HCO(,3), and SO(,4) whereas Na shows an apparent net loss. The retention of Ca, Mg and HCO(,3) suggests that less than 25% of the dolomitic liming materials applied to the landscape actually dissolve and that the carbonate chemistry of Lower Coastal Plain streams is therefore probably largely controlled by seepage of groundwaters from underlying calcareous aquifers. The retention of K and the loss of Na may be due to cation exchange reactions on soil clays whereas the apparent retention of SO(,4) is probably due to reduction to H(,2)S in floodplain environments and soil adsorption.
Show more [+] Less [-]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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