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21.

We examine the dynamics and spatial determinants of land change in India by integrating decadal land cover maps (1985–1995–2005) from a wall-to-wall analysis of Landsat images with spatiotemporal socioeconomic database for ~630,000 villages in India. We reinforce our results through collective evidence from synthesis of 102 case studies that incorporate field knowledge of the causes of land change in India. We focus on cropland–fallow land conversions, and forest area changes (excludes non-forest tree categories including commercial plantations). We show that cropland to fallow conversions are prominently associated with lack of irrigation and capital, male agricultural labor shortage, and fragmentation of land holdings. We find gross forest loss is substantial and increased from ~23,810 km2 (1985–1995) to ~25,770 km2 (1995–2005). The gross forest gain also increased from ~6000 km2 (1985–1995) to ~7440 km2 (1995–2005). Overall, India experienced a net decline in forest by ~18,000 km2 (gross loss–gross gain) consistently during both decades. We show that the major source of forest loss was cropland expansion in areas of low cropland productivity (due to soil degradation and lack of irrigation), followed by industrial development and mining/quarrying activities, and excessive economic dependence of villages on forest resources.

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22.
On-site sanitation has emerged as a preferred mode of sanitation in cities experiencing rapid urbanization due to the high cost involved in off-site sanitation which requires conventional sewerages. However, this practice has put severe stress on groundwater especially its quality. Under the above backdrop, a study has been undertaken to investigate the impact of on-site sanitation on quality of groundwater sources in two mega cities namely Indore and Kolkata which are situated in two different geological settings. The parameters for the studies are distance of groundwater source from place of sanitation, effect of summer and monsoon seasons, local hydro-geological conditions, and physico-chemical parameters. NO3 and fecal coliform concentrations are considered as main indexes of pollution in water. Out of many conclusions which can be made from this studies, one major conclusion is about the influence of on-site sanitation on groundwater quality is minimal in Kolkata, whereas it is significant in Indore. This difference is due to the difference in hydrogeological parameters of these two cities, Kolkata being on alluvium quaternary and Indore being on Deccan trap of Cretaceous to Paleogene age.  相似文献   
23.
Environmentally safe disposal of end-of-life (EoL) or discarded mobile phone is a serious problem on account of their ever increasing number and toxic metals contents. In the present work, metal toxicity of mobile phone plastics, printed wire boards (PWBs) and batteries were assessed through dynamic batch leaching using Milli Q (MQ) water. Phone plastics failed Toxicity Characterization Leaching Procedure (TCLP) and Waste Extraction Test (WET) for Pb as the cumulative amount of Pb leached from plastics (5.33 mg/l) exceeded the regulatory limits (5.0 mg/l) used in characterizing a waste as hazardous. Similarly, the average cumulative amount (21.83 mg/l) of Ni leached from PWBs exceeded the regulatory limit of 20 mg/l and thus PWBs failed WET. Metals leached from batteries in small amounts (Cr: 0.40 mg/l and Ni: 0.15 mg/l). The presence of Fe in the batteries and its precipitation as oxides/hydroxides in the leaching solution hindered the leaching of other metals in MQ water. Both plastics and PWBs should be treated as hazardous waste and should not be disposed in open landfills. Further, MQ water leaching could provide good simulation of metals leaching from the mobile phones disposed at landfill sites.  相似文献   
24.
Our study explores the nexus between forests and local communities through participatory assessments and household surveys in the central Himalayan region. Forest dependency was compared among villages surrounded by oak-dominated forests (n = 8) and pine-dominated forests (n = 9). Both quantitative and qualitative analyses indicate variations in the degree of dependency based on proximity to nearest forest type. Households near oak-dominated forests were more dependent on forests (83.8%) compared to households near pine-dominated forests (69.1%). Forest dependency is mainly subsistence-oriented for meeting basic household requirements. Livestock population, cultivated land per household, and non-usage of alternative fuels are the major explanatory drivers of forest dependency. Our findings can help decision and policy makers to establish nested governance mechanisms encouraging prioritized site-specific conservation options among forest-adjacent households. Additionally, income diversification with respect to alternate livelihood sources, institutional reforms, and infrastructure facilities can reduce forest dependency, thereby, allowing sustainable forest management.  相似文献   
25.
This study has investigated the common risks associated with the water quality changes from the source to the consumer households and the associated disease burden in the piped water supplies. Samples from the source to the household storage from Nagpur City were collected and analysed for heavy metals, nutrient and microbial parameters. Sanitary risks were identified at the households during the socio-economic and sanitary survey. The water quality deterioration was the most at household storage around 30.3 % indicating that measures need to be taken to safeguard the water quality at the consumer level. Then, 31.2 % of the samples collected from public standposts and handpumps were positive for faecal contamination which implies that it is the weaker sections of the society who suffer the consequences of drinking unsafe water the most. On the basis of the laboratory results, risk analysis by surveying the WTPs, point-of-use behaviour at households and sanitary status at different socio-economic strata, the Water Safety Plan for Nagpur City was structured. The aim was to ensure that safe and improved water is reached to the individual household.  相似文献   
26.
Environmental Science and Pollution Research - The present study describes geochemical facie and implications of rock-water interaction at the groundwater of Chamba city. The influence of rock...  相似文献   
27.
The mangrove formations of Godavari estuary are due to silting over many centuries. The estuary covers an area of 62,000 ha of which dense Coringa mangrove forest spread in 6,600 ha. Satellite sensor data was used to detect change in the mangrove cover for a period of 12 years (1992-2004). It was found that an area of about 1,250 ha of mangroves was destroyed by anthropogenic interference like aquaculture, and tree felling etc. It was found that mangrove's spectral response/digital number (DN) value is much lower than non-mangrove vegetation such as plantation and paddy fields in SWIR band. By taking this as an advantage, spectral data was utilized for clear demarcation of mangroves from nearby paddy fields and other vegetation. Simpson's diversity index, which is a measure of biodiversity, was found to be 0.09, showing mangroves dominance. Ecological parameters like mud-flats/swamps, mangrove cover alterations, and biodiversity status are studied in detail for a period of 12 years. The increase in mangrove front towards coast was delineated using remote sensing data. The major advantages of remote sensing data is monitoring of change periodically. The combination of moderate and high-resolution data provided detailed coastal land use maps for implementing coastal regulation measures. The classification accuracy has been achieved is 90%. Overall, simple and viable measures are suggested based on multi-spectral data to sustain this sensitive coastal ecology.  相似文献   
28.
Heat pipe cooling is widely used in computer processors. Advances in microprocessor technology have resulted in reduced heat transfer surface area. Maintaining an efficient cooling process is therefore challenging. The main goal of this experimental study is to perform a parametric study on heat pipe performance using nanofluids. Nanofluids of 1 and 3 vol% of alumina nanoparticles of 20–50 nm diameters in deionized water versus deionized water as a base fluid were considered in the present study. The nanofluids are prepared in our laboratory using two-step method. The nanofluids thermal properties are measured to confirm the properties enhancement that could indicate a corresponding performance enhancement of the heat pipe. A 10 mm inner diameter, 200 mm long brass tube with 50 mm long evaporator, and 50 mm long water cooled condenser were used. Heat pipe wall temperature is reduced with nanofluids as is the temperature difference between the evaporator and condenser. The thermal diffusivity of the nanofluids is increased by 10%. The pipe pressure in case of deionized water was higher than the corresponding one for the nanofluids by 20–32%.  相似文献   
29.
Data obtained from full‐time employees of a public sector organization in India were used to test a social exchange model of employee work attitudes and behaviors. LISREL results revealed that whereas the three organizational justice dimensions (distributive, procedural and interactional) were related to trust in organization only interactional justice was related to trust in supervisor. The results further revealed that relative to the hypothesized fully mediated model a partially mediated model better fitted the data. Trust in organization partially mediated the relationship between distributive and procedural justice and the work attitudes of job satisfaction, turnover intentions, and organizational commitment but fully mediated the relationship between interactional justice and these work attitudes. In contrast, trust in supervisor fully mediated the relationship between interactional justice and the work behaviors of task performance and the individually‐ and organizationally‐oriented dimensions of citizenship behavior. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
30.
Conventional blanket application of nitrogen (N) fertilizer results in more loss of N from soil system and emission of nitrous oxide, a greenhouse gas (GHG). The leaf color chart (LCC) can be used for real-time N management and synchronizing N application with crop demand to reduce GHG emission. A 1-year study was carried out to evaluate the impact of conventional and LCC-based urea application on emission of nitrous oxide, methane, and carbon dioxide in a rice–wheat system of the Indo-Gangetic Plains of India. Treatments consisted of LCC scores of ≤4 and 5 for rice and wheat and were compared with conventional fixed-time N splitting schedule. The LCC-based urea application reduced nitrous oxide emission in rice and wheat. Application of 120 kg N per hectare at LCC ≤ 4 decreased nitrous oxide emission by 16% and methane by 11% over the conventional split application of urea in rice. However, application of N at LCC ≤ 5 increased nitrous oxide emission by 11% over the LCC ≤ 4 treatment in rice. Wheat reduction of nitrous oxide at LCC ≤ 4 was 18% as compared to the conventional method. Application of LCC-based N did not affect carbon dioxide emission from soil in rice and wheat. The global warming potential (GWP) were 12,395 and 13,692 kg CO2 ha−1 in LCC ≤ 4 and conventional urea application, respectively. Total carbon fixed in conventional urea application in rice–wheat system was 4.89 Mg C ha−1 and it increased to 5.54 Mg C ha−1 in LCC-based urea application (LCC ≤ 4). The study showed that LCC-based urea application can reduce GWP of a rice–wheat system by 10.5%.  相似文献   
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