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991.
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
992.
The distribution of three important dissolved forms of nitrogen, viz. nitrate, nitrite and urea in the surface and bottom water samples collected from 27 selected hydrographic profiles, in the Arabian Sea, along the west coast of India is described. Of the three forms, nitrate concentrations were the highest and comparatively higher concentrations were observed in the bottom water. Decomposition of organic matter resulting in the release of the thermodynamically stable nitrogen species, i.e. nitrate, may be the major factor resulting in higher nitrate concentrations at these depths, where the water is also characterized by low values of dissolved oxygen and temperature. The significant positive correlation between A.O.U. and nitrate of the bottom water samples emphasizes the role of oxidative decomposition of organic matter which plays an active role in reducing the oxygen concentrations below the theoretical values since at this depth ( ≈200 m) the net production is taken to be zero. This is also evidenced by the negative correlation of nitrate with dissolved oxygen and temperature, for the bottom samples. 相似文献
993.
Early identification of the critical environmental issues arising from new energy technologies is needed to ensure adequate consideration of these issues in all phases of research and development. This study examines the potential hazards to aquatic ecosystems from large-scale exploitation (190,000 Mg/day) of the Chattanooga Shale Formation, an immense reserve of oil shale and uranium in Kentucky, Tennessee, and Alabama. Using existing data on regional ecology, hydrology, mining operations, and raw and spent shale chemistry, we identified two major, related environmental issues: (1) the potential for extensive adverse effects on aquatic communities through degradation of water quality and habitat; and (2) the potential conflict between the requirements for shale exploitation, and the habitat and water quality needs of threatened or endangered species. Specific hazards to aquatic ecosystems include erosion, sedimentation, acid mine drainage, raw and spent shale leachates, and surface disposal of immense quantities of solid wastes. Twelve of 19 federally designated, threatened or endangered fish and mollusks in the shale-bearing region were identified as known or recent inhabitants of the counties believed to be most favorable for the exploitation of shale. Of these, five species occur as single populations or are limited to a single river system. The potential for adverse effects on these species is greatest in the counties near the Tennessee-Alabama state line. Future research needs include physical, chemical, and toxicological characterizations of shale leachates and studies of the transport and fate of leachable contaminants. Such research can provide the guidance necessary to minimize impacts on aquatic communities resulting from extraction, retorting, and disposal of shale. 相似文献
994.
分布在剑川县城西侧的一系列碱性浅成斑岩-深成岩体,不是彼此孤立而是一个具有成因联系的杂岩体.该杂岩体可分为四次岩浆侵入,其中第Ⅱ次剑川粗面斑岩并不是过去认为的粗面岩,而是一个超浅成侵入体,从中心到边部可分为两个岩相带,岩石以碱性系列为主,岩浆是深熔作用形成的. 相似文献
995.
Tommy Gärling 《Journal of environmental psychology》1982,2(3):233-251
Environmental psychology research in Sweden is reviewed beginning with studies in the 1960s. The traditional main foci of the Swedish research are the visual perception of form, space, colour, and texture, the meaning of social and physical environments; and the effects of the indoor and outdoor ambient environment (noise, air quality and temperature). More recent research foci include environmental cognition (perceptual categorization, cognitive mapping, orientation, planning), affective reactions to the environment, and systems applications. It is concluded that the Swedish research is integrated with environmental psychology research in other countries in terms of a common data base and methodology, despite the fact that the problems investigated are to some extent national in tone. It is also pointed out that the Swedish research appears to have the potential of theoretical contributions to environmental psychology, which is badly needed within the field as a whole. 相似文献
996.
William E. Sharpe 《Journal of the American Water Resources Association》1975,11(3):546-550
ABSTRACT: Recent watershed research indicates that many timber management practices have profound effects on the water quality of small headwater streams. These streams often support fisheries of high value. Current knowledge seems to indicate that a definite potential exists for a symbiotic relationship between timber and fisheries management. Maximum development of both resources is attainable only if further research efforts recognize the mutually benefiting aspects of these heretofore separate disciplines. Future research should carefully examine the complex interrelationships between small headwater aquatic ecosystems and the riparian forest environment. 相似文献
997.
Marshall Gysi 《Journal of the American Water Resources Association》1975,11(3):551-558
ABSTRACT: The present energy and environmental crises are due to increasing per capita demands as well as increasing populations. The role that traditional pricing policies have played in promoting these demands is discussed. The reduction or stabilizing of per capita demands is advocated through the use of Conservational Pricing mechanisms which charge higher average prices for high consumption. An example of the effect of Conservational Pricing in the water supply industry is given. 相似文献
998.
基于12个微量元素、10个稀土元素和24个同位素分析结果,作者认为本区钾质火山岩系中超基性岩和极大多数基性岩有接近原生岩浆的成分,岩浆都是地幔岩石低程度部分熔融形成的,其源岩成分为受流体交代的金云母石榴石二辉橄榄岩。综地球化学、地球物理及地质三方面资料分析,论证本区火山活动的构造背景是大陆裂谷。 相似文献
999.
A number of studies have observed differences in the evaluation of visual, aesthetic stimuli between those with and without professional training in art and design. If exposure to design training underlies such differences it follows that evidence of training effects should be observable when comparing subjects at different stages of design training, and not observable when comparing subjects at different stages of non-design training. In addition, this evidence should be consistent with directional predictions. The study reported in this paper investigated this question using a sample of 192 trained and untrained subjects in an evaluative task. Subjects were from two departments (Design and Computer Studies) of the same educational establishment and comprised balanced groups of lecturers, 1st, 2nd and 3rd year undergraduate students. The results obtained demonstrated evaluative differences and patterns of association both within and between the subject groups consistent with a training hypothesis. 相似文献
1000.