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541.
Ammonia toxicity tests were performed with Labeo bata (bata) larvae of three different size groups. One hundred percent survival of larvae (500.0?±?4.0?mg) was recorded when exposed to ammonia concentrations of 1.0–13.56?mg?L?1 at 96?h of exposure. Bata larvae exposed to ammonia concentrations of 15.8–25?mg?L?1 showed 10–74% mortalities. The 96?h LC50 value for 200 (±5), 250 (±2) and 500 (±4) mg bata larvae were 11.5, 16.8 and 22.5?mg?L?1 un-ionised ammonia concentrations, respectively. When fish were exposed to different doses of ammonia, behavioural changes immediately occurred even at the lowest dose. At first, the fish became hyperexcitable, the skin darkened and they showed an increased ventilation frequency, fish behaviour became normal, 24?h after exposure. A 96?h LC50 value of un-ionised ammonia showed direct relationship with the increasing size of bata larvae.  相似文献   
542.
Environmental Science and Pollution Research - The study was conducted to monitor concentration of six toxic metals in faecal pellets of blue rock pigeon from six industrial areas of Jaipur, i.e....  相似文献   
543.
Environmental Science and Pollution Research - The spatial and vertical distributions of radon and uranium are evaluated in relation to the hydrogeology, geomorphology, and hydrochemistry of...  相似文献   
544.
The Khanikhola watershed in Sikkim is agrarian with about 50% area under rain-fed agriculture representing the conditions of the middle mountains all over the Himalaya. The study was conducted to assess overland flow, soil loss and subsequent nutrient losses from different land uses in the watershed, and identify biotechnological inputs for management of mountain farming systems. Overland flow, soil and nutrient losses were very high from open agricultural (cropped) fields compared to other land uses, and more than 72% of nutrient losses were attributable to agriculture land use. Forests and large cardamom agroforestry conserved more soil compared to other land uses. Interventions, like cultivation of broom grass upon terrace risers, N2-fixing Albizia trees for maintenance of soil fertility and plantation of horticulture trees, have reduced the soil loss (by 22%). Soil and water conservation values (> 80%) of both large cardamom and broom grass were higher compared to other crops. Use of N2-fixing Albizia tree in large cardamom agroforestry and croplands contributed to soil fertility, and increased productivity and yield. Bio-composting of farm resources ensured increase in nutrient availability specially phosphorus in cropped areas. Agricultural practices in mountain areas should be strengthened with more agroforestry components, and cash crops like large cardamom and broom grass in agroforestry provide high economic return and are hydroecologically sustainable.  相似文献   
545.
Life cycle assessment (LCA) provides a concept, framework, and method to identify and evaluate the environmental burdens of products and processes. An ongoing concern of companies trying to implement LCA is the value of LCA in supporting actual decisions versus the resources and time needed to conduct a “full” LCA. In response to these concerns, there has been a lot of activity surrounding the “streamlining” of LCA to keep it more manageable yet provide useful and acceptably accurate results. This article explores the concept of streamlining, discusses where and how streamlining decisions can be made in an LCA, and presents issues related to conducting more streamlined LCAs. Due to the wide variety of purposes and scenarios in which LCAs are conducted, it is difficult to devise a one-size-fits-all method for streamlining. Instead, we have focused on presenting the streamlining options in the context of major decision points that are common to most LCAs.  相似文献   
546.
547.
Ground water quality in two well-developed cities of Haryana, viz. Hisar and Panipat was assessed for drinking purpose based on water quality parameters like pH, EC, turbidity, TDS, alkalinity, total hardness, calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), chloride (Cl), nitrate (NO3), phosphate (PO4), sulphate (SO4) and fluoride (F) with respect to different land-use areas viz. residential, industrial, commercial and agricultural. Water quality index based on 9 parameters showed that at Panipat, underground water in all the land-use zones was fit for consumption (WQI < 50), whereas at Hisar, water in agricultural areas was good in quality, but that in other areas varied in magnitude of pollution (WQI > 50 to 100).  相似文献   
548.
Environmental contamination by pesticides has been documented in biotic and abiotic components. These persistent organic pollutants are lipid soluble, nonbiodegradable, and endocrine disrupters. The present study was therefore planned to determine whether the levels of these pesticides like DDT and its metabolites DDD and DDE, dieldrin, heptachlor, and HCH and its isomers (alpha, beta, and gamma) were higher in blood of breast cancer patients when compared with normal women who did not suffer from major diseases like blood pressure, tuberculosis, diabetes, thyroid dysfunction, arthritis, cancer, etc. and had not undergone any major surgery. The results indicated that organochlorine pesticides taken for analysis were found significantly high in breast cancer patients irrespective of age, diet, and geographic distribution.  相似文献   
549.
Various pollution indicators of stream Ban-Ganga have been identified on the basis of presence/absence/numerical abundance at various stations. They have been categorized as pollution tolerant, facultative and pollution intolerant groups in relation with the water quality at different stations of stream.  相似文献   
550.
Impact of temperature related seasonal changes in density of Golgi complex were studied in brain, heart and intestine of the freshwater catfish, Clarias batrachus (Linnaeus). The density of Golgi complex was more in these organs of the fish acclimatized to a lower temperature (20 degrees C) than that to a higher temperature (29 degrees C). This suggests that lower temperature induces secretory activity in cells to cope up with the changes in surrounding environment. It could be a kind of histophysiological adaptation in poikilothermic animal.  相似文献   
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