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131.
Ecological economics is a field of enquiry that has had, with a few exceptions, an almost entirely terrestrial focus. Given the fundamental ecological and economic importance of oceanic and coastal ecosystems, and the accelerating deterioration of these ecosystems, we argue that there is an urgent case to redress this imbalance. In so doing, the scope of ecological economics will be extended and compelling insights developed and applied to better understand and govern marine systems. Although we acknowledge that there is no unequivocal or unitary view of what might constitute an ecological economics of the oceans and coasts, we assert that it should consist of at least ‘four cornerstones’: (1) sustainability as the normative goal; (2) an approach that sees the socio-economic system as a sub-system of the global ecological system; (3) a complex systems approach; and (4) transdisciplinarity and methodological pluralism. Using these four cornerstones, we identify a future research agenda for an ecological economics of the oceans and coasts. Specifically, we conclude that ecological economists must work with other disciplines, especially those involved in marine policy and practice, to move from a ‘frontier economics’ (which has dominated marine management) to entrench an ‘ecological economics’ of the oceans and coasts as the dominant paradigm.  相似文献   
132.
Over the past ten years, total mercury (THg) levels have been surveyed in Alaskan wildlife and fish as part of the Arctic Monitoring and Assessment (AMAP). Beyond these studies there is little historical data on THg levels in important subsistence species for people in Alaska. A survey of THg in caribou hair from archaeological deposits would provide data to develop temporal trends for this region of the Arctic. Caribou hair from a Western Thule settlement beneath the Alaska native village of Deering (ca. AD 1150) show variability in hair THg values, with a mean level (86 ng/g) which is in the range that is observed in modern Rangifer sp. (caribou and reindeer). Hair from House 1 had a THg mean level of 99.6 ng/g and hair from House 2 had a THg mean of 64.2 ng/g. This is the earliest reported record of mercury in caribou associated with human subsistence activities in the western North American Arctic, and is a first step toward compilation of a needed database through which to measure and evaluate exposure to mercury by people who rely heavily on caribou as a food source. We hypothesize that similarity in mercury values in archaeological samples of caribou and in contemporary samples would give an additional perspective on human exposure to mercury through caribou harvest and consumption today. Since this hypothesis will be more useful if evaluated at a regional rather than global scale, further studies will be needed at different archaeological sites across Alaska to determine the generality of this observation in relation to geographic scale.  相似文献   
133.
Summary. Leaf disc choice and oviposition bioassays were used to examine the effects of larval experience with a Hoodia gordonii latex on subsequent behaviors. The latex deterred feeding and oviposition by “naïve” cabbage looper (Trichoplusia ni, Noctuidae) larvae and moths with no previous exposure to the material. “Experienced” insects, reared on a diet with the H. gordonii latex (1000 ppm), exhibited lesser feeding deterrence relative to naïve insects. Experienced female moths actually preferred to lay eggs on treated rather than control leaves. There was no observed transfer of behavioral preferences from experienced parents to their offspring. Our results suggest that moths may be acquiring oviposition preferences from larval feeding experience as described by Hopkins’ host selection principal (HHSP) or through chemical legacy.  相似文献   
134.
Monitoring of the waters in the U.S. is a dynamic process, which has evolved with environmental legislation. In the past, water monitoring was directed at the conventional sanitary parameters. However, over the years, water monitoring has evolved to include various toxic compounds. Several federal agencies and States are now actually involved in monitoring and data are easily accessible through widely used data storage and retrieval systems. Recently, the U.S. Environmental Protection Agency published a Basic Water Monitoring Program, which gives new direction to the conduct of water monitoring at the State level.  相似文献   
135.
136.
Endocrine disrupting compounds(EDCs) and pharmaceuticals pose a challenge for water and wastewater treatment because they exist at very low concentrations in the presence of substances at much higher concentrations competing for adsorption sites.Sub-micron sized resin particles(approximately 300 nm in diameter)(SMR) were tested to evaluate their potential as a treatment for EDCs including:17-β estradiol(E2),17-α ethinylestradiol(EE2),estrone(E1),bisphenol A(BPA),and diethylstilbestrol(DES) as well as 12 pharmaceuticals.SMR were able to remove 98%of spiked E2,80%of EE2,87%of BPA,and up to 97%of DES from water.For a 0.5 ppm mixture of E2,EE2,E1,BPA and DES,the minimum removal was24%(E2) and the maximum was 49%(DES).They were also able to remove the pharmaceuticals from deionized water and wastewater.Overall,SMR are a promising advanced treatment for removal of both EDCs and pharmaceuticals.  相似文献   
137.
The substitution of biogas, an energy source derived from biological feedstock, for fossil natural gas (NG) can mitigate the build-up of greenhouse gases in the atmosphere, making it an attractive renewable energy source in a carbon-constrained future. Although upgraded, pipeline-quality biogas can augment the NG market supply in the United States of America (USA), researchers and energy industry experts have little studied its long-term potential. This report estimates (1) levelized costs of energy for biogas production facilities operating with landfill waste, animal manure, wastewater sludge, and biomass residue feedstocks, (2) feedstock and technology pathway-specific biogas supply functions, and (3) the aggregate national biogas supply potential for the USA by 2040. Under a range of specified assumptions, generation of biogas could be expanded to approximately 3–5 % of the total domestic NG market at projected prices of $5–6/MMBtu, with the largest potential source coming from thermal gasification of agriculture and forest residues and biomass. As market signals have not spurred widespread adoption of biogas in the USA, policy incentives, similar to those used in the European Union (E.U.), may be necessary to increase its production and use. Bioenergy policy in the E.U. and the resulting market penetration achieved there therefore provides important lessons for how biogas markets in the USA can overcome barriers to market expansion and, in doing so, provide substantial climate mitigation benefits.  相似文献   
138.
Using forests to mitigate climate change has gained much interest in science and policy discussions. We examine the evidence for carbon benefits, environmental and monetary costs, risks and trade-offs for a variety of activities in three general strategies: (1) land use change to increase forest area (afforestation) and avoid deforestation; (2) carbon management in existing forests; and (3) the use of wood as biomass energy, in place of other building materials, or in wood products for carbon storage. We found that many strategies can increase forest sector carbon mitigation above the current 162-256 Tg C/yr, and that many strategies have co-benefits such as biodiversity, water, and economic opportunities. Each strategy also has trade-offs, risks, and uncertainties including possible leakage, permanence, disturbances, and climate change effects. Because approximately 60% of the carbon lost through deforestation and harvesting from 1700 to 1935 has not yet been recovered and because some strategies store carbon in forest products or use biomass energy, the biological potential for forest sector carbon mitigation is large. Several studies suggest that using these strategies could offset as much as 10-20% of current U.S. fossil fuel emissions. To obtain such large offsets in the United States would require a combination of afforesting up to one-third of cropland or pastureland, using the equivalent of about one-half of the gross annual forest growth for biomass energy, or implementing more intensive management to increase forest growth on one-third of forestland. Such large offsets would require substantial trade-offs, such as lower agricultural production and non-carbon ecosystem services from forests. The effectiveness of activities could be diluted by negative leakage effects and increasing disturbance regimes. Because forest carbon loss contributes to increasing climate risk and because climate change may impede regeneration following disturbance, avoiding deforestation and promoting regeneration after disturbance should receive high priority as policy considerations. Policies to encourage programs or projects that influence forest carbon sequestration and offset fossil fuel emissions should also consider major items such as leakage, the cyclical nature of forest growth and regrowth, and the extensive demand for and movement of forest products globally, and other greenhouse gas effects, such as methane and nitrous oxide emissions, and recognize other environmental benefits of forests, such as biodiversity, nutrient management, and watershed protection. Activities that contribute to helping forests adapt to the effects of climate change, and which also complement forest carbon storage strategies, would be prudent.  相似文献   
139.
In Da Nang and Ha Long, Vietnam and in Vientiane, Laos, there was interest by local authorities in separating and composting waste in order to reduce environmental and health problems at the local landfills and to produce a soil conditioner for local agricultural use. To assist in the planning of composting projects, three studies were carried out to estimate waste quantities and composition. 1. A 9-day audit of waste from 45 vendors in a market in Vientiane, the capital of Laos. The total quantity of waste and the quantity in each of nine categories were estimated for each of six different types of vendors. 2. A 7-day audit of waste disposed by three hotels in the tourist area of Ha Long, Vietnam. Waste quantities were estimated in total, on a per guest basis, and in three main categories: compostables, recyclables and miscellaneous. 3. A 7-day audit of waste collected from 74 households in Da Nang, the fourth largest city in Vietnam. Waste from each household was separated into compostable and non-compostable waste. Over 60% of each waste source comprised compostable waste and this was considered significant enough to warrant further planning of composting operations.  相似文献   
140.
双盲测试是一种经典的测试方法,适用于测试结果依赖人的影响或解释的情况.本文记录Sandia国家实验室对MOLE可编程探测系统进行双盲测试的整个过程,包括测试准备、测试设计、测试参数设定、进行测试、测试结果分析和讨论.  相似文献   
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