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41.
Large-scale industrialization, population inflow, and rapid urbanization coupled with unfavorable meteorological conditions often induce significant degradation of urban environment. In order to assess the extent of environmental impacts due to establishment of the Integrated Industrial Estate??Pantnagar (IIE-Pantnagar), ambient air and groundwater were monitored from June 2007 to May 2008. Collected baseline information was normalized and interpreted with the application of air (AQI) and water quality indices (WQI). Among the pre-identified air pollutants, suspended particulate matter was found to be the principal culprit to deteriorate ambient air quality, with a maximum annual concentration of 418.5 ??g/m3. Monthly average concentrations of respirable particulate matter (aerodynamic diameter < 10 ??m) also persist at a critical level with an annual maximum of 207.3 ??g/m3. A segmented linear function with maximum operator concept was used to compute AQI, and the developed index was found well suitable to demonstrate temporal variations of ambient air quality. The computed AQI value for the selected study region varied from moderate (97.0) to very poor pollution level (309.2) in respect to developed air quality standards. Furthermore, an integrated WQI was developed comprising 9 parameters, and among all the 10 pre-identified locations, the average groundwater quality was found acceptable in terms of Indian drinking water standards. The maximum WQI (70.6) was found at the Kichha Railway Station during summer months, revealing moderate pollution load. Industrial discharge from IIE-Pantnagar coupled with other industrial setup may hold responsible for such kind of degradation of water quality. In contrast, WQI computed at Rudrapur City demonstrate minimum (15.0?C22.1) pollution load. For 95% of the monitoring period, the computed WQI was found acceptable for all selected locations with few exceptions. The application of WQI to assess temporal variations in groundwater quality was therefore found satisfactory.  相似文献   
42.
The residue dynamics of carbendazim and mancozeb in grape berries is reported. The fungicides were sprayed in accordance with the most critical use pattern i.e. 4 times at 15 days interval separately at recommended and double doses. The residues of each fungicide dissipated following 1st order rate kinetics. The half-lives of carbendazim and mancozeb were 7.3 and 8.1 days at recommended dose and 4.6 and 5.7 days at double dose. Ethylenethiourea (ETU), the toxic metabolite of mancozeb was detectable at harvest following four sprays of mancozeb at recommended dose. At double dose, however, the residues of ETU could be detected even after three sprays of mancozeb. The pre-harvest intervals for carbendazim and mancozeb were found to be 26 and 12 days at recommended dose and 33 and 17 days at double dose, respectively.  相似文献   
43.
Kolkata, home of 4.5 million people, is generating 1112 million liters of sewage per day and facing the challenge of managing this wastewater. The 125 km2 wide wetland on the eastern fringe of the city, popularly known as the East Kolkata Wetlands is serving as a natural sewage treatment plant for more than a century where nearly 78 % of city sewage goes through an intricately designed canal network. This wetland is a designated RAMSAR site where the sewage treatment process is a rare example of an intertwined symbiotic relation between wastewater treatment and wetland aquaculture, where livelihood dependence of the local people on sewage-fed fisheries becomes of strategic importance in sustainable performance of the system. An aggressive urban expansion in the eastern fringe of the city is disturbing this age-old eco-balance by making this sewage water pisciculture less profitable. There is push factor due to reduced attraction of the wastewater fisheries and a pull factor due to emergence of alternative livelihood options through rapid urbanization. To protect wetland in its original form, the civil society and the administrative authorities are designing active interventions. However, these are not generating expected results as these instruments are targeting to mitigate the push factor only without paying much heed to the push–pull interactions.  相似文献   
44.
The alterations in the salinity profile are an indirect, but potentially sensitive, indicator for detecting changes in precipitation, evaporation, river run-off, glacier retreat, and ice melt. These changes have a high impact on the growth of coastal plant species, such as mangroves. Here, we present estimates of the variability of salinity and the biomass of a stenoecious mangrove species (Heritiera fomes, commonly referred to as Sundari) in the aquatic subsystem of the lower Gangetic delta based on a dataset from 2004 to 2015. We highlight the impact of salinity alteration on the change in aboveground biomass of this endangered species that, due to different salinity profile in the western and central sectors of the lower Gangetic plain, shows an increase only in the former sector, where the salinity is dropping and low growth in the latter, where the salinity is increasing.  相似文献   
45.
Journal of Material Cycles and Waste Management - Distillation by-products of two Ocimum sp. were recycled through extraction of phenolic compounds and development of functional material like...  相似文献   
46.
Progress of the Indian economy is threatened by the impact of climate change. Generation of urban heat islands (UHIs), waning of urban green cover, increase in carbon emissions and air pollution deteriorate the living environment. Rise in urban temperatures and heat stress induced mortality remain major concerns. Although the National Action Plan on Climate Change emphasises the national missions of ‘enhanced energy efficiency’, and ‘green India’, little research has been devoted to explore the passive cooling potential of urban greenery in India, thus lending uniqueness to this study. The manifestations of unplanned urban development (UHIs, escalated carbon emissions, air pollution) are discussed and corroborated with identification of contributory factors. Contemporary greening practices and bye-laws in four major Indian cities (New Delhi, Pune, Chennai, and Visakhapatnam) are analysed and compared with global best practices. The findings are used to propose planning guidelines which are expected to assist in consolidating natural sustainability of emerging economies.  相似文献   
47.
The rate of degradation of kresoxim methyl and its effect on soil extra-cellular (acid phosphatase, alkaline phosphatase and β-glucosidase) and intra-cellular (dehydrogenase) enzymes were explored in four different soils of India. In all the tested soils, the degradation rate was faster at the beginning, which slowed down with time indicating a non-linear pattern of degradation. Rate of degradation in black soil was fastest followed by saline, brown and red soils, respectively and followed 1st or 1st + 1st order kinetics with half-life ranging between 1–6 days for natural soil and 1–19 days for sterile soils. The rate of degradation in natural against sterilized soils suggests that microbial degradation might be the major pathway of residue dissipation. Although small changes in enzyme activities were observed, kresoxim methyl did not have any significant deleterious effect on the enzymatic activity of the various test soils in long run. Simple correlation studies between degradation percentage and individual enzyme activities did not establish any significant relationships. The pattern and change of enzyme activity was primarily due to the effect of the incubation period rather than the effect of kresoxim methyl itself.  相似文献   
48.
Recognition of the social costs associated with traditional practices of urban waste management in India led to the formulation of Municipal Waste Management and Handling rules (2000). However, compliance with the proposed collection and disposal involves higher commitment in terms of both time and money on the part of the residents, local bodies as well as the state and central government. In this context, information about the value of the environmental improvements conferred upon the city dwellers would be important from the planner’s perspective. Given the non-market characteristic of waste disposal services, we infer about beneficiaries’ perceived demand for the proposed service by means of Double-Bounded Dichotomous Choice Contingent Valuation Survey conducted in the Bally Municipality in the district of Howrah, West Bengal. We estimate the average WTP by controlling for anchoring bias and use the annualized value of cost to examine the feasibility of the proposed system.  相似文献   
49.
The long-lived radionuclide 79Se is one of the elements of concern for the safe storage of high-level nuclear waste, since clay minerals in engineered barriers and natural aquifer sediments strongly adsorb cationic species, but to lesser extent anions like selenate (SeVIO4(2-)) and selenite (SeIVO3(2-)). Previous investigations have demonstrated, however, that SeIV and SeVI are reduced by surface-associated FeII, thereby forming insoluble Se0 and Fe selenides. Here we show that the mixed FeII/III (hydr)oxides green rust and magnetite, and the FeII sulfide mackinawite reduce selenite rapidly (< 1 day) to FeSe, while the slightly slower reduction by the FeII carbonate siderite produces elemental Se. In the case of mackinawite, both S(-II) and FeII surface atoms are oxidized at a ratio of one to four by producing a defective mackinawite surface. Comparison of these spectroscopic results with thermodynamic equilibrium modeling provides evidence that the nature of reduction end product in these FeII systems is controlled by the concentration of HSe(-); Se0 forms only at lower HSe(-) concentrations related to slower HSeO3(-) reduction kinetics. Even under thermodynamically unstable conditions, the initially formed Se solid phases may remain stable for longer periods since their low solubility prevents the dissolution required for a phase transformation into more stable solids. The reduction by Fe2+-montmorillonite is generally much slower and restricted to a pH range, where selenite is adsorbed (pH < 7), stressing the importance of a heterogeneous, surface-enhanced electron transfer reaction. Although the solids precipitated by the redox reaction are nanocrystalline, their solubility remains below 6.3 x 10(-8) M. No evidence for aqueous metal selenide colloids nor for Se sorption to colloidal phases was found. Since FeII phases like the ones investigated here should be ubiquitous in the near field of nuclear waste disposals as well as in the surrounding aquifers, mobility of the fission product 79Se may be much lower than previously assumed.  相似文献   
50.
The sorption behavior of the insecticide thiamethoxam [3-(2-chloro-1,3-thiazol-5-ylmethyl)-5-methyl-1,3,5-oxadiazinan-4-ylidene(nitro)amine] on three Indian soils with different physico-chemical properties was investigated. The soils represent the major grapevine growing areas of India, where the vineyards frequently receive thiamethoxam applications as foliar spray, soil drenching and through drip irrigation for the management of various insect pests. The rate constants for adsorption and desorption at two different temperatures were obtained from the Lindstrom model, which simultaneously evaluated adsorption and desorption kinetics. The data for rate constants, activation energies, enthalpy of activation, entropy of activation and free energy indicated physical adsorption of thiamethoxam on soil. The adsorptivity of different soils might be attributed to the organic matter and clay contents. A good fit to the linear and Freundlich isotherms was observed for both adsorption as well as desorption. Thiamethoxam could be categorized as a chemical with medium leaching potential.  相似文献   
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