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41.
New institutional economists have argued that there are many categories of institutions, including market and non-market institutions, which may prove economically efficient, specifically for public goods and common pool goods. The Government of India introduced a non-market community-based institution, known as Joint Forest Management (JFM), for forest management and protection in 1990. JFM is a sharing mechanism for forest planning and management based on sharing of rights and duties, control and decision-making authority over forestlands, between forest departments and local user groups. By 2001, 42 000 Village Forest Committees established under JFM were managing over 11.5 million ha forestland. These institutions have proved very useful, and have contributed to forest management as well as four aspects of sustainable human development (SHD) – ecological output, income generation, village infrastructure development, and community empowerment. In the long-term, community-based institutions will prove to be a foundation of SHD and participatory democracy.  相似文献   
42.
Ziram, a dithiocarbamate fungicide, is extensively used in crop protection. Daily oral doses of ziram (5 and 25 mg kg(-1) day(-1)) for 30, 60 and 90 days produced significant mortality in male rats. The fungicide also caused a significant increase in the thyroid:body weight ratio, histological changes, and a reduced activity of thyroid (125)I uptake and protein bound (125)I. However, the animals did not show any change in the clinical enzyme profile of the liver, serum and brain. It is believed that ETU, the degradation product of ziram and a known antithyroid compound, is the causative agent for the high mortality, as well as for the pronounced thyrostatic and hepatotoxic effects found in the experimental animals.  相似文献   
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Summary It has been shown in recent surveys, that in India there is an upward trend in the area of open forest, which has grown from 10.06 million ha to 26.32 million ha in a few years. But the closed forests of India have registered a fall from 36.02 million ha to around 33 million ha. The latter fact is both significant and disturbing. It proves that in spite of the Forest Conservation Act, 1980, the process of degeneration of forests, in India, constantly continues. It is obvious that a part of the open forests must have come from closed forests due to the reckless denudation of forests, carried out in the name of development. A massive afforestation/reforestation programme is desired to achieve the target of one third of the geographical area of the country to be under forest cover for proper ecological balance. India has to develop a sound National Forest Policy to meet the requirements of the country, to produce industrial wood, for forest based industries, defence, communication and other public purposes, and small timbers fuel wood and fodder for the rural community. In this context the decision taken by the Control Board of Forestry in December, 1987, is quite encouraging. It was resolved that the extraction of wood from the forests would be stopped and the country's need for timber and fuelwood would be met by importing wood and by means of farm forestry. The reconstitution of the National Wasteland Development Board and the planting target of 5 million ha p.a. are other positive steps in this direction. Extensive research is needed for a better and new approach to social and commercial forestry.Dr Om Prasad, the senior author, is a biologist in the Department of Zoology, University of Allahabad. He is responsible for developing a number of Environmental Biology Courses at graduate and post-graduate level. Besides being actively engaged in research on the adverse toxilogical effects of a number of commonly used food additives, he supports environmental protection activities including the provision of guidance to the Students Nature Club which is affiliated to WWF-India.Dr Pawan Kumar, after teaching for seven years in the Department of Forestry at Birsa Agricultural University, Ranchi, Bihar, recently joined the Department of Environment of the Government of India where he is in charge of a number of environmental projects. Dr O.N. Pandey is a specialist in Forestry teaching at Birsa Agricultural University, India.  相似文献   
45.
Since sewage discharges can significantly contribute to the contaminant loadings in coastal areas, it is important to identify sources, pathways and environmental sinks. Sterol and fatty alcohol biomarkers were quantified in source materials, suspended sediments and settling matter from the Ria Formosa Lagoon. Simple ratios between key biomarkers including 5beta-coprostanol, cholesterol and epi-coprostanol were able to identify the sewage sources and effected deposition sites. Multivariate methods (PCA) were used to identify co-varying sites. PLS analysis using the sewage discharge as the signature indicated approximately 25% of the variance in the sites could be predicted by the sewage signature. A new source of sewage derived organic matter was found with a high sewage predictable signature. The suspended sediments had relatively low sewage signatures as the material was diluted with other organic matter from in situ production. From a management viewpoint, PLS provides a useful tool in identifying the pathways and accumulation sites for such contaminants.  相似文献   
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This paper identifies newer areas of arsenic contamination in the District Kanker, which adjoins the District Rajnandgaon where high contamination has been reported earlier. A correlation with the mobile phase episodes of arsenic contamination has been identified, which further hinges on the complex geology of the area. Arsenic concentrations in both surface and groundwater, aquatic organisms (snail and water weeds) soil and vegetation of Kanker district and its adjoining area have been reported here. The region has been found to contain an elevated level of arsenic. All segments of the ecoysystem are contaminated with arsenic at varying degrees. The levels of arsenic vary constantly depending on the season and location. An analysis of groundwater from 89 locations in the Kanker district has shown high values of arsenic, iron and manganese (mean: 144, 914 and 371 μg L−1, respectively). The surface water of the region shows elevated levels of arsenic, which is influenced by the geological mineralised zonation. The most prevalent species in the groundwater is As(III), whereas the surface water of the rivers shows a significant contamination with the As(V) species. The analysis shows a bio-concentration of the toxic metals arsenic, nickel, copper and chromium. Higher arsenic concentrations (groundwater concentrations greater than 50 μg L−1) are associated with sedimentary deposits derived from volcanic rocks, hence mineral leaching appears to be the source of arsenic contamination. Higher levels of arsenic and manganese in the Kanker district have been found to cause impacts on the flora and fauna. A case study of episodic arsenical diarrhoea is presented.  相似文献   
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Environmental Science and Pollution Research - Secondhand smoke (SHS) accounts for 0.9 million deaths and 24 million disability adjusted life years (DALYs) annually. Nearly 30% of adults in India...  相似文献   
49.

As a global pollutant, Hg (Hg) since the turn of the last century has received increased attention. Decreasing the emission of Hg into the food chain and the atmosphere is an effective way to reduce the Hg damage. The current study provided information about pilot-scale horizontal subsurface flow (HSSF) constructed wetlands (CWs) to remove different Hg species in polluted water. Synthetic wastewater was fed to two HSSF CWs, one was planted with Acorus calamus L and the other was unplanted as a control. The total Hg (THg), dissolved Hg (DHg), and particulate Hg (PHg) from five sites along the HSSF CWs were analyzed to describe the process of Hg removal. Results show that the CWs have high removal efficiency of Hg which is more than 90%. The removal efficiencies of THg and DHg from the unplanted CW were 92.1?±?3.6% and 72.4?±?13.1%, respectively. While, the removal efficiencies of THg and DHg in planted CW were 95.9?±?7.5% and 94.9?±?4.9%, which were higher than that in blank CW. The PHg was mainly removed in the first quarter of the CWs, which was also revealed by the partition coefficient Kd. To a certain extent, the effect of plants depends on the hydraulic retention time (HRT). The results in the current study show the potential of the HSSF-CWs for restoration from Hg-contaminated water.

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50.
What role does an ego's brokerage location—within a team (intra‐team) or outside the team (inter‐team)—play in the evolution of an instrumental knowledge‐seeking network in terms of both proximal (i.e., within the team) and distal (i.e., outside the team) tie formation and tie decay? We address this question by drawing on literature about social networks, brokerage, and teams. We use temporally separated data from 302 students embedded in 97 teams to test our hypotheses about the impacts of intra‐team and inter‐team brokerage on proximal and distal network evolution, specifically on four network changes in knowledge‐seeking networks: proximal tie formation, proximal tie decay, distal tie formation, and distal tie decay. We find that these four changes depend on individual network brokerage location even after controlling for personality and task characteristics. Specifically, inter‐team brokers change their networks both within and outside their teams, whereas intra‐team brokers curtail their network changes. We argue that these opposite effects occur because inter‐team brokers have greater autonomy than intra‐team brokers. This study adds to the ongoing dialog about network evolution in social network literature and to the conversations about brokerage and its location in the context of team‐based work.  相似文献   
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