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11.
The appraisal of sustainability: Some problems and possible responses   总被引:1,自引:0,他引:1  
The development of 'indicators' and associated techniques for the appraisal of 'sustainability' requires efforts to systematically define, quantify and aggregate many disparate dimensions of social, environmental and economic performance. This necessarily raises a number of serious theoretical and methodological difficulties, including those relating to the selection and framing of 'problems' and 'options', the treatment of deep uncertainties and the 'impossibility' of aggregating in analysis the divergent social interests and value judgements which govern the prioritisation of the different dimensions of 'sustainability'. After exploring the depth and scope of some of these difficulties, this paper argues that they render futile any attempt to develop an 'analytical fix' for the problems of appraisal. In this light, systematic public participation is recognised not just as an issue of political efficacy and legitimacy, but also as a fundamental matter of analytical rigour. However, it is also concluded that once aspirations to the 'analytical fix' are renounced, there is much that might be contributed by transparent, straightforward quantitative analytical tools and the paper ends with some recommendations and an example in this regard.  相似文献   
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Juvenile bass, Dicentrarchus labrax (L.), fed ad libitum on trout pellets, the shore crab Carcinus maenas and filleted saithe, Gadus virens, did not differ significantly in proximate composition although the diets were absorbed with high efficiencies of 94 to 99% and differed greatly in composition. Compared with wild fish, the white muscle, dark muscle, liver and mesenteric fat bodies of laboratory-reared bass were lower in moisture and higher in lipid. Starvation caused a rapid initial decrease in carbohydrate and a progressive decline in lipid in all tissues, coupled with an increase in moisture and ash contents. The liver and fat body somatic indices also declined, indicating that these organs are the major lipid storage depots in bass, in contrast with the skeletal muscle which has this role in other active fishes such as salmonids and clupeids. Lipid and protein are inversely related to moisture content in whole specimens.  相似文献   
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Conservation science deals with crises and supports policy interventions devised to mitigate highly uncertain threats that pose irreversible harm. When conventional policy tools, such as quantitative risk assessments, are insufficient, the precautionary principle provides a practical framework and range of robust heuristics. Yet, precaution is often resisted in many policy arenas, especially those involving powerful self-interests, and this resistance is compounded by structures of privilege and competitive individualism in science. We describe key drivers and effects of such resistance in conservation science. These include a loss of rigor under uncertainty, an erosion of crisis response capabilities, and a further reinforcement of privileged interests in conservation politics. We recommend open acknowledgement of the pressures exerted by power inside science; greater recognition for the value of the precautionary principle under uncertainty; deliberate measures to resist competitive individualism; support for blind review, open science, and data sharing; and a shift from hierarchical multidisciplinarity toward more egalitarian transdisciplinarity to accelerate advances in conservation science. Article impact statement: Precautionary principle, privilege structures among disciplines, and culture of individualism link to effective conservation policy making.  相似文献   
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Hazardous waste remediation technologies are rapidly evolving, and it is a challenge for environmental consultants and those working in the government and public sectors to remain current with those technologies. Fortunately, the U.S. Environmental Protection Agency (EPA), through a variety of programs and initiatives, has been a leader in providing information on hazardous waste remediation technologies. This article provides an overview of EPA remediation programs and guides the reader through valuable EPA information sources including publications, databases, and on-line services.  相似文献   
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One-year-old rope-grown blue mussels (Mytilus edulis L.) were held in experimental lantern nets and cross-transplanted between two sea lochs (Lochs Etive and Leven) on the west coast of Scotland. Growth and mortality were monitored from May 1991 to May 1992, as well as shell morphology in native and transplanted mussels. There were highly significant differences (P0.001) in growth rates between lochs; both native and transplanted mussels performed better in all shell and tissue growth-parameters in Loch Etive than in Loch Leven. Stock also had a significant (P0.05) influence on shell length and live weight, but its contribution to total variance was considerable only in the latter case. Wet and ash-free dry meat weights were governed mainly by site and to some extent by site x stock interaction. Mortality rates were quite low (6 to 7% yr-1) and did not show any significant variation either between sites or stocks. There were significant morphological differences (ratios of shell length, height and width) between the Loch Etive and Loch Leven populations (P0.001) which persisted for one year after transfer. Stock appeared to be the main factor affecting shell morphology, as opposed to site. Linear regressions of shell height and width on length were significantly different between the native stocks, but became indistinguishable from those of the recipient populations one year after reciprocal transfer. This did not, however, conceal the effect of stock origin on dimensional ratios. It is concluded that site differences related to environmental factors, notably chlorophyll a levels and currents, and also possible stress caused by high levels of Zn and Cu, are major determinants of growth, which are of main interest to aquaculture, while morphological differences most probably result from genotypic variation.  相似文献   
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