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51.
Noise level monitoring and its reduction with different width and height of vegetation belt were studied in the Varanasi city. Noise level monitoring of the Varanasi city revealed the fact that area category A (without vegetation) was highly polluted as compare to area category B (with vegetation) having less fluctuation of traffic load. Four plant species Putranjeva roxburghi, Cestrum nocturnum, Hibiscus rosasinensis and Murraya peniculata were tested for noise reduction study at different frequencies. Experiment revealed the fact that H. rosasinensis reduced noise highest at both low and high frequencies (100-500 Hz, 22 dB and 2.5-6.3 KHz 26 dB), followed by M. peniculata (100-500 Hz, 18 dB and 2.5-6.3 KHz 20 dB), P. roxburghi (100-500 Hz 15 dB and 2.5-6.3 KHz 17 dB) and C. nocturnum (100-500 Hz 9 dB and 2.5-6.3 KHz 14 dB). Significance of vegetation belt in noise reduction was established with multiple regression models.  相似文献   
52.
Conversion of broad-spectrum organic waste into carbonaceous biochar has gained enormous interest in past few years. The present study aims to characterize feedstock (FS), i.e. bagasse (Bg), bamboo (Bm) and biochar (BC), i.e. baggase biochar (BBg), bamboo biochar (BBm) and tyre biochar (Ty). Significant changes in elemental composition, atomic ratio, proximate analyses, mineral content and heavy metal content were observed which was well supported by Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) analysis. Impregnation with ferric hydroxide was done, and resultant modified biochars (MBC), i.e. iron-impregnated baggase biochar (FeBBg), iron-impregnated bamboo biochar (FeBBm) and iron-impregnated tyre biochar (FeTy), along feedstock and biochar were used for PO4 3?, Pb, Hg and Cu adsorption. In general, BBg, FeBBg, BBm, FeBBm, Ty and FeTy were found to adsorb PO4 3?, Pb, Hg and Cu better than Bg and Bm, except in few cases. Results from adsorption experiments were fitted into Langmuir, Freundlich and Temkin models of isotherms and pseudo-first-order, pseudo-second-order and Elovich models of kinetics. Result of batch study adsorption revealed that maximum adsorption of PO4 3?, Pb, Hg and Cu was done by FeBBg (adsorption mechanism explained by Freundlich model), FeTy (Temkin model), Ty (Langmuir model) and BBm (Langmuir model) respectively. According to R 2 values, pseudo-first-order reaction was well suited to PO4 3?, Pb, Hg and Cu adsorption. The optimum pH for maximum adsorption was observed to be 7.4 for PO4 3?, 5 for Cu and 6 for Pb and Hg respectively  相似文献   
53.
Sri Lanka being an agrarian country, the role of water is important for agricultural production. In Sri Lanka, various tank cascade systems, earthen dams and distribution canals have been accepted as few of the most complex ancient traditional water systems of the world. Rainfall, surface water, groundwater and runoff are linked with each other, they have close interactions to land cover classes such as forests and agriculture. The monitoring of vegetation conditions can show subsurface manifestations of groundwater. In this study, an effort to understand the role of traditional water reservoirs and groundwater recharge was made using remote sensing techniques. We have analyzed various vegetation indices such as Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI-2), Soil-Adjusted Vegetation Index (SAVI), tasselled cap transformation analysis (TCA brightness, greenness and wetness) and their relations with the existence of soil, vegetation and water. Result shows that EVI, SAVI, and TCA-based Greenness Index indicates good relationship with the vegetation conditions as compared to other indices. Therefore, these indices could play a crucial role in depicting the interaction between soil, vegetation, and water. However, multi-temporal observations can provide significant results about these interactions more accurately.  相似文献   
54.
The effects of varying concentrations of urea, phosphogypsum and paper mill sludge (PMS) on the morphology, histology, tissue protein content, lipid peroxidation (LPX), activities of lactate dehydrogenase (LDH), acetylcholinesterase (AChE) and catalase in earthworms Drawida willsi and Lampito mauritii have been studied over an exposure period of 24?hr. Integumentary lesions, clitellar swelling and loss of pigmentations were found to be major morpho-pathological changes in the worms. Histology indicated cuticular damage, ruptured epithelium and muscle fibres with accumulation of cellular debris. Lowest tissue protein content (57.02?±?4.02?mg/g tissue) and highest LPX (0.113?±?0.04, 0.137?±?0.08?nmol/mg protein) were noticed in D. willsi at a high concentration of PMS, whereas highest tissue protein content was observed in L. mauritii (115.32?±?7.18?mg/g tissue) with the same treatment. In both the species, LDH activity was minimum at a high concentration of urea (0.172?±?0.02; 0.247?±?0.08?U/mg protein). AChE activity was highest (0.099?±?0.002?U/mg protein) at a high concentration of PMS in D. willsi, whereas catalase activity was the maximum (0.338?±?0.02?U/mg protein) at high concentrations of PMS in L. mauritii. The study indicated that morpho-histological and enzymatic alterations in these earthworms exposed to agrochemicals could be useful biomarkers to evaluate soil toxicity.  相似文献   
55.
Present investigation was done to evaluate various algal genera found in water bodies of Varanasi city. The potential of any biomass for biofuels (bioalcohols, biohydrogen, etc.) production depends on the quantity of extractable sugar present in it. Acid (H2SO4) and alkali (NaOH) pretreatment were performed, and H2SO4 was chosen due to its nearly double yield as compared with alkaline pretreatment. Response surface methodology was utilized for the optimization of operating parameters such as treatment temperature, time, and acid concentration. Sugar yield up to 0.33 g/g of dry biomass was obtained using cyanobacterial biomass of Lyngbya limnetica, at 100°C, 59.19 min, and H2SO4 concentration of 1.63 M.  相似文献   
56.
Summary A comparative study of Survey of India topo-maps of 1929 and land satellite imageries in False Colour Combination (FCC) of 1975 indicates a loss of 43% and 46% of the reserved forest around Sambalpur and Jharsuguda respectively, besides other forest types in a radius of twenty miles. Deforestation is found to be an accelerating process where the rate of loss is estimated to be more during 1970–75 and 1960–70 in comparison to 1950–60 from a semilogarithmic trend curve between 1929 and 1975. This curve also fits to a hypothesis that the rate of deforestation is faster after 1950 (after developmental plan periods came into force). An analysis of the climatic data indicates a decrease in rainfall and number of rainy days, and morning relative humidity. The mean minimum and maximum temperature, evening relative humidity and atmospheric pressure show increasing trends. Relationships between forest loss and climatic parameters are significant for morning relative humidity, rainy days, maximum temperature and atmospheric pressure. Considering the loss of storage capacity of the Hirakud reservoir due to severe deforestation in the catchment area, suggestions are given for natural forest preservation. Arttabandhu Mishra graduated in Science (Zoology Honours) and Education from Utkal University; postgraduated from Berhampur University, India. At present he is a Lecturer in School of Life Sciences, Sambalpur University and Secretary of Orissa Environmental Consciousness Society. His fields of interests are Productivity and Energetics of Forest Ecosystems, Environmental Education and Community Education. He has published seven papers on the above fields and a number bf popular articles. He tries to use folk literature as media to carry scientific messages. Madhab C. Dash, obtained his B.Sc. (Hens), M.Sc. from Utkal University, India and Ph.D. from University of Calgary, Canada. At present he is Professor and Head, School of Life Sciences, Sambalpur University, a fellow of the Zoological Society of India, the National Institute of Ecology and the National Academy of Sciences, India. His major areas of research and writing are on the functional role of soil organisms in the decomposer subsystem of ecosystems, He has published seventy-five papers on taxonomy, biology, population ecology, metabolic functions, energy flow modelling, role in soft fertility and waste conditioning ability of Oligochaetes, nematodes, protozoa and soil microorganisms. Professor Dash has contributed specialised chapters in major treaties published by Cambridge University Press, UK; John Wiley and Sons, USA; and Academic Press, New York, USA.  相似文献   
57.
58.
Using farm level data we evaluate the input use and environmental effects of revenue insurance. A priori, the moral hazard effect on input use is indeterminate. This paper empirically assesses the input use impact of the increasingly popular, and federally subsidized, risk management instrument of revenue insurance and the extent to which its effects on input use may differ from those of the older yield based instruments. We conclude that among winter wheat farmers, those who purchase revenue insurance tend to spend less on fertilizers but do not appreciably alter pesticide expenditures. Thus, any improved environmental outcomes due to crop insurance are likely due to reduced fertilizer not pesticide use. When the environmental indicators included indicated a potential environmental fragility (i.e. high erosion, pesticide leaching or pesticide runoff potential), the input use equation suggested that fertilizer expenditures decreased. Revenue insurance undoubtedly further reduces fertilizer applications on these fields as well, but the marginal environmental benefit of revenue insurance is lessened because the reduction, where it matters most, accrues on land on which fertilizer use has already been curtailed to some degree.  相似文献   
59.
A numerical model which simulates the decomposition of litter and mineralization and immobilization of P in the humus layer of a temperate forest (beech site of Solling) is described. The model takes into account the effect of moisture, temperature and C/N ratio. The simulated concentration of P in the effluent of the humus layer agrees well with the measured values. The model predicts an increase in the C/P ratio of the unde-composed litter with time and that there is no direct mineralization of P from litter without passing through a microbial body. The net rate of mineralization is, however, always positive with its highest peak in July. Maximum immobilization of P from solution occurs in June and the minimum in January.The model is stable against changes in the litter input, its C/P ratio and other initial conditions, but it is very sensitive to changes in the efficiency factor which represents the fraction of decomposed C incorporated into microbial tissue. This is a site-specific model but can be used for grassland or agricultural systems with changes in certain parameters.  相似文献   
60.
Samples of foliose lichen, Dirinaria consimillis (Fr.) Awasthi were transplanted at six residential sites of Lucknow city for monitoring the concentration of Cr, Zn, Pb, Cu and Cd metals at two vertical positions. The concentration of chromium and copper were more at the higher vertical position than the lower one. The maximum zinc was at lower vertical position than the upper one. Lead and cadmium were not detected in the present study.  相似文献   
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