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91.
Statistical prediction is a tool and aim in ecology and wildlife management and conservation. A prediction may either be supported by or contradicted by observations of an unknown set of observations. A contradiction occurs if the prediction is not included within the range of the unknown observations, i.e. the prediction misses the cloud of observations completely. Mixed-effects models, frequently used for statistical assessment of clustered data, carry information needed for calculating the probability of such contradictions. Here we present a new versatile statistic, the probability of contradiction (P (Contra)), that describes how often we would anticipate a new cluster of observations contradicting our predictions. Some benefits of P (Contra) are: (1) easy to calculate and intuitive interpretation, (2) comparability between datasets, (3) inclusion of residual correlation, (4) summary of the multitude of information from mixed models into one statistics, and (5) applicable to local mixed-effect models.  相似文献   
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93.
A newly constructed coastal revetment at Colhuw Beach in the Glamorgan Heritage Coast, Wales, UK, was analysed using a recently developed environmental risk assessment package (ERA). Conflict with Heritage Coast conservation objectives is apparent and the act of building such a structure is questioned for a location where maintenance ofnatural beauty is an axiom of the coastal management philosophy. The likelyhood of revetment related environmental consequences of significant magnitude was analysed using estimated probability values derived from Bayesian theory. The damaging impact of the structure on the natural environment is out of all proportion to the level of storm protection afforded to the site. Analyses, such as carried out via ERA, would have shown planners, engineers and environmentalists, the inadequacies of such an investment and management strategy. The ERA approach can help to introduce greater clarity and consistency into decision making processes.  相似文献   
94.
A newly constructed coastal revetment at Colhuw Beach in the Glamorgan Heritage Coast, Wales, UK, was analysed using a recently developed environmental risk assessment package (ERA). Conflict with Heritage Coast conservation objectives is apparent and the act of building such a structure is questioned for a location where maintenance ofnatural beauty is an axiom of the coastal management philosophy. The likelyhood of revetment related environmental consequences of significant magnitude was analysed using estimated probability values derived from Bavesian theory. The damaging impact of the structure on the natural environment is out of all proportion to the level of storm protection afforded to the site. Analyses, such as carried out via ERA, would have shown planners, engineers and environmentalists, the inadequacies of such an investment and management strategy. The ERA approach can help to introduce greater clarity and consistency into decision making processes.  相似文献   
95.
/ We identified and ranked 108 resident and migratory wildlife taxa on John F. Kennedy Space Center (KSC) that were vulnerable to local, regional, or global extinction. We ranked taxa based on their vulnerability to extinction, their potential role for maintaining faunal integrity, and the relevance of KSC for maintaining their populations in the United States and Florida. Several taxa, not listed by agencies, were vulnerable to regional or global extinction. Many taxa not vulnerable to global extinction were vulnerable to local and regional extinction. Top predators were vulnerable to extinction because of small population size, isolation from other populations, and road mortality. Many taxa were dependent on habitat conditions at different geographic locations so that conservation required greater collaboration among land owners, managers, and researchers at local, regional, and global scales.KEY WORDS: Biological diversity; Endangered species; Conservation  相似文献   
96.
Although climate change risks have been studied for a number of economic sectors, banking has received relatively little attention. The paper proposes a methodology and an associated decision-support tool for quantifying, in monetary terms, the risks for banks from the exposure of their loan recipients and/or applicants to climate change. The framework and tool are applied to a case study based on input from a Greek bank; results indicate that climate change risks for banks are considerable, and thus decision makers need to estimate their magnitude and possibly consider these within the credit management process, and in environmental planning.  相似文献   
97.
近年来,水文部门根据降水预报,探索流域洪水模拟预报,对密切监视暴雨洪水、做好防汛调度决策起到良好作用。文章在统计分析小凌河多年暴雨洪水的基础上,采用不同雨级平均24 h时段比率,进行凌河保护区洪水模拟预报成果编制研究。构建"以流域为单元、以干流为主线、以水库和河道水文站为控制节点"的流域河库联合模拟预报调度成果图表,实现流域水系河库模拟预报调度。通过科学的实时洪水调度可以调蓄洪水,减轻洪水灾害。同时,也可为流域洪水资源化提供保障和科学依据,实现流域的综合管理。  相似文献   
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99.
ABSTRACT: The Conservation Areas in South Florida have been considered as one of the major water storage areas to provide a water supply for the Everglades National Park and Lower East Coast (LEC). Due to the increasing water demands of the area, additional backpumping of the surplus runoff from the LEC area into the Conservation Areas has been considered as one of several alternative plans. The Receiving Water Quantity (EPA, 1971) model has been adapted and modified to be applicable in the Conservation Areas to investigate the possible impact of additional inflow under various backpumping cases. The modification of the model included Manning's roughness coefficient, depth of flow, width of hypothetical channels through marsh areas, rainfall input, seepage rate, etc. The use of the Monte Carlo technique for area computations was found to be easy and time saving both in area and weighting rainfall input to each node. Comparison of results generated by this modified model with the recorded values in Conservation Areas 1 and 2A indicated that the model not only can be a very good evaluation tool to simulate the hydraulic regime of the Conservation Areas system but also a proper tool for investigating the impact of additional inflow resulting from the backpumping related to the water use planning and management.  相似文献   
100.
This paper evaluates the impact of fluctuating electricity prices on the cost of five options to increase the water supply to urban areas in Southern California—new surface storage, water purchases, desalination, wastewater recycling, and conservation.We show that the price of electricity required to produce and transport water influences the cost of water supply options and may alter the decision makers economic ranking of these options. When electricity prices are low, water purchase is the cost effective option. When prices exceed US$ 86/MWh, conservation of electricity and water through installation of high efficiency clothes washers is the most effective option.  相似文献   
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