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171.
Geochemical study of groundwater from a structurally deformed granitic terrain near Hyderabad (India) was carried out to understand
and evaluate the hydrogeochemical processes and quality of groundwater. Several trace elements (Fe, Mn, Be, Al, V, Cr, Co,
Ni, Cu, Zn, As, Sr, Mo, Cd, Sb, Ba, Pb, U) along with major ions and minor elements were precisely estimated in shallow and
drilled wells to know the suitability of water for drinking and irrigation purposes. Analytical data shows that pH and major
ion chemistry in dug wells and bore wells do not vary significantly, while some trace elements (Fe, Mn, Al, Be, Co, Pb, U
and Zn) vary in dug wells and bore wells, which can be attributed to differential mineral weathering and dissolution/precipitation
reactions along fractures/joints. Although the water is not potable, it was found to be suitable for irrigation with little
danger in the development of harmful level of exchangeable sodium. It is inferred that the chemical composition of the groundwater
in this region is likely to have its origin from silicate weathering reactions and dissolution/precipitation processes supported
by rainfall and groundwater flow. 相似文献
172.
Tilak KS Veeraiah K Rao DK 《Journal of environmental biology / Academy of Environmental Biology, India》2005,26(1):73-77
The freshwater fish Catla catla, Labeo rohita and Cirrhinus mrigala are exposed to the toxicant chlorpyrifos, an organo phosphate commonly used in agriculture as well as in aquaculture. The effect was studied on the enzyme acetyl cholinesterase activity which was inhibited in the selected tissues of the fish. In different tissues and in brain, the maximum inhibition was observed. 相似文献
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Some aspects of the habitat zones, distribution pattern, and population density with reference to tidal levels of the tropical limpet Cellana radiata (Born) are presented. Observations have also been made on the homing behaviour of the limpet. Unlike the temperate limpets, no migration to different tidal levels during different seasons was observed in C. radiata. 相似文献
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欧盟绿色壁垒对我国出口产品的影响分析 总被引:2,自引:0,他引:2
欧盟绿色壁垒虽然从客观上促使我国加强环境保护、推进可持续发展战略,但也严重限制了我国主要出口产品的对欧贸易。“绿色”外衣下掩盖的是贸易保护的实质。我国惟有努力提高环保标准和管理水平,提高企业和产品的环境竞争力,才能有效突破绿色壁垒,力争贸易与环保双赢。 相似文献