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The Indian Himalayan Region (IHR) is suffering from environmental degradation due to population pressure and infra-structural needs. This is coupled with a natural setting, which creates problems of accelerated soil erosion and mass wasting. In view of these environmental difficulties and the growing concern for effective restoration, there has become an urgent need for multi-disciplinary coordinated improvement schemes. The mitigation of risk arising from hazardous mass wasting processes, through a careful and systematic approach, has helped in the development of the concept of Mountain Risk Engineering (MRE). The MRE practices involve an integrated approach to solving the infra-structural engineering problems of hilly and mountainous areas through environmentally conscious cost-effective and site-specific designs. However, the role of people's participation is extremely crucial for the success of such programs. This paper analyzes the perception of the local people about the approaches adopted in MRE participatory developmental programs and throws light on the intricacies of peoples' participation.  相似文献   
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Monitoring of heavy metals was conducted in the Yamuna River considering bioaccumulation factor, exposure concentration, and human health implications which showed contamination levels of copper (Cu), lead (Pb), nickel (Ni), and chromium (Cr) and their dispersion patterns along the river. Largest concentration of Pb in river water was 392 μg L?1; Cu was 392 μg L?1 at the extreme downstream, Allahabad and Ni was 146 μg L?1 at midstream, Agra. Largest concentration of Cu was 617 μg kg?1, Ni 1,621 μg kg?1 at midstream while Pb was 1,214 μg kg?1 at Allahabad in surface sediment. The bioconcentration of Cu, Pb, Ni, and Cr was observed where the largest accumulation of Pb was 2.29 μg kg?1 in Oreochromis niloticus and 1.55 μg kg?1 in Cyprinus carpio invaded at Allahabad while largest concentration of Ni was 174 μg kg?1 in O. niloticus and 124 μg kg?1 in C. carpio in the midstream of the river. The calculated values of hazard index (HI) for Pb was found more than one which indicated human health concern. Carcinogenic risk value for Ni was again high i.e., 17.02?×?10?4 which was larger than all other metals studied. The results of this study indicated bioconcentration in fish due to their exposures to heavy metals from different routes which had human health risk implications. Thus, regular environmental monitoring of heavy metal contamination in fish is advocated for assessing food safety since health risk may be associated with the consumption of fish contaminated through exposure to a degraded environment.  相似文献   
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Imidacloprid is extensively used on a broad range of crops worldwide as seed dressing, soil treatment, and foliar application. Hence, the degradation potential of bacterial strains from sugarcane-growing soils was studied in liquid medium for subsequent use in bioremediation of contaminated soils. The microbe cultures degrading imidacloprid were isolated and enriched on Dorn’s broth containing imidacloprid as sole carbon source maintained at 28 °C and Bacillus alkalinitrilicus showed maximum potential to degrade imidacloprid. Clay loam soil samples were fortified with imidacloprid at 50, 100, and 150 mg kg?1 along with 45?×?107 microbe cells under two opposing sets of conditions, viz., autoclaved and unautoclaved. To study degradation and metabolism of imidacloprid under these two conditions, samples were drawn at regular intervals of 7, 14, 28, 35, 42, 49, and 56 days. Among metabolites, three metabolites were detected, viz., 6-chloronicotinic acid, nitrosimine followed by imidacloprid-NTG under both the conditions. Total imidacloprid residues were not found to follow the first-order kinetics in both types of conditions. This paper reports for the first time the potential use of pure cultures of soil-isolated native bacterium B. alkalinitrilicus and also its use along with natural soil microflora for remediation of imidacloprid-contaminated soils.  相似文献   
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Chlorantraniliprole, an anthranilic diamide insecticide with novel mode of action, is found effective against several lepidopteran as well as coleopteran, dipteran, and hemipteran pests. The present studies were carried out to study the persistence pattern of chlorantraniliprole on sugarcane field soil following application of granule formulation. The residues of chlorantraniliprole were estimated using high performance liquid chromatograph (HPLC) and confirmed by liquid chromatograph-mass spectrometry (LC-MS/MS). Following application of chlorantraniliprole (Ferterra 0.4G) at 100 and 200 g a.i. ha?1, the average initial deposits of chlorantraniliprole were observed to be 0.88 and 1.59 mg kg?1, respectively. These residues dissipated below the limit of quantification (LOQ) of 0.01 mg kg?1 after 56 days of the application of insecticides at both the dosages. The half-life values (t 1/2) of chlorantraniliprole were worked out to be 8.36 and 8.25 days, at recommended and double the recommended dosages, respectively.  相似文献   
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Traditional water harvesting systems are multi-functional in nature and provide a variety of ecosystem services that contribute to the overall wellbeing of local people. This study aims to identify and analyze the factors influencing the variations in the level of awareness across households residing around three selected traditional water bodies in the Indian state of West Bengal. Ordinary least square (OLS) regression models have been used to identify and analyze the determinants of household perception on ecosystem services from tank water bodies. Results show that while a majority of households have strong perceptions on the provisioning and cultural ecosystem services of the tanks, the household perceptions on regulating and supporting services of the tank is found to be relatively weak. Households belonging to lower caste and poor are likely to be more dependent on ecosystem services from tanks than upper caste and rich households, and hence they have better perceptions of provisioning ecosystem services. Households’ awareness about provisioning ecosystem services is negatively related to their level of education and wealth. It is observed that household awareness about regulating and supporting ecosystem services is positively associated with the level of education of the households, ownership of tube well and private tanks. While it is essential to consider household perception on all the ecosystem services for sustainable use and management of traditional water harvesting systems, incorporating the local norms, customs and preferences in policy design are critical for achieving effective conservation outcomes.  相似文献   
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The automobile exhausts are one of the major sources of particulate matter in urban areas and these particles are known to influence the atmospheric chemistry in a variety of ways. Because of this, the oxidation of dissolved sulfur dioxide by oxygen was studied in aqueous suspensions of particulates, obtained by scraping the particles deposited inside a diesel truck exhaust pipe (DEP). A variation in pH showed the rate to increase with increase in pH from 5.22 to about ~6.3 and to decrease thereafter becoming very slow at pH?=?8.2. In acetate-buffered medium, the reaction rate was higher than the rate in unbuffered medium at the same pH. Further, the rate was found to be higher in suspension than in the leachate under otherwise identical conditions. And, the reaction rate in the blank reaction was the slowest. This appears to be due to catalysis by leached metal ions in leachate and due to catalysis by leached metal ions and particulate surface both in suspensions. The kinetics of dissolved SO2 oxidation in acetate-buffered medium as well as in unbuffered medium at pH?=?5.22 were defined by rate law: k obs ?=?k 0?+?k cat [DEP], where k obs and k 0 are observed rate constants in the presence and the absence of DEP and k cat is the rate constant for DEP-catalyzed pathway. At pH?=?8.2, the reaction rate was strongly inhibited by DEP in buffered and unbuffered media. Results suggest that the DEP would have an inhibiting effect in those areas where rainwater pH is 7 or more. These results at high pH are of particular significance to the Indian subcontinent, because of high rainwater pH. Conversely, it indicates the DEP to retard the oxidation of dissolved SO2 and control rainwater acidification.

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