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211.
Coastal archaeological resources around the world often coincide with dense contemporary human populations and a rapidly changing physical environment. Projected sea level rise and urban expansion during the 21st century threaten to destroy much of our global coastal archaeological heritage. In this study, we adapt an environmental vulnerability analysis to quantify the threats of modern development and sea level rise on archaeological sites in California’s Santa Barbara Channel region. Using spatial and statistical techniques, we create a Cultural Resource Vulnerability Index that combines environmental factors, current and projected urban footprints, and archaeological site positioning. We illustrate the importance of this method for targeting threatened archaeological sites for mitigation and salvage research. In the process, we highlight the significance of coastal archaeological sites for helping better understand contemporary environmental and cultural issues, underscoring the need to preserve or salvage these sites for their significant research value.  相似文献   
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213.
Analyzing ecotones to predict biotic productivity   总被引:1,自引:0,他引:1  
A technique for predicting the potential biotic productivities of areas is presented. The simple method uses maps or other techniques of remote imagery in comparing adjacent terrestrial and/or littoral areas for investigations when ground reconnaissance is not feasible. Theedge index, the statistical basis for comparison, is calculated as the ratio of the length of a particular ecotone (for example, timberline or shoreline) that would be affected by a proposed development to the affected land area. In similar habitats an unbiased comparison results at the ordinal level of measurement. The method predicts that a higher edge index will correspond to a higher productivity. But because it is not established whether or not the relationship is somehow scalar, the method is not recommended for comparing greatly dissimilar or far distant areas.It has long been observed that ecotones (edges) where two biotic communities meet often produce more game than pure stands of either community. The reasons for this edge effect are reviewed. The demonstrably higher productivity of ecotones is partially explained in terms of the mechanisms that also account for diversity of species.An attempt is made to reconcile theoretical treatments of species diversity with the pragmatic methods for reaching conclusions, which are employed by specialists in resource management.  相似文献   
214.
This paper examines variation in local perceptions of risk in semi-arid Tanzania, identifying factors that influence local perceptions of problems and testing the feasibility of risk mapping as a technique. Twelve villages in six districts were visited between February and April 2001. Villagers were asked about their worries and concerns in providing for themselves and their families using a risk questionnaire. The responses were grouped into 21 categories of problem and incidence and severity indices were calculated for each category. Most problems were associated with the availability of natural resources on which livelihoods depend but others related to human and social capital assets. In addition to environmental factors, livelihood strategy and gender both influenced people's perceptions of risk. Problems of irrigation and weather, for example, were important for agricultural communities while problems relating to livestock diseases, access to land and hunger were more important in pastoral communities. The risks cited by men and women generally reflected their traditional roles in society. Very broadly, the risks associated with natural capital tended to be seen as higher by men while women mentioned more problems relating to human and social capital. However, this was not always the case. Problems linked to finance, traditionally the concern of men, were ranked similarly by men and women. In projects designed to facilitate community management and control over common pool resources, the identification of common interests is particularly important. Risk mapping can provide a cost-effective way of gaining insights to help improve research design and to inform policy development.  相似文献   
215.
ABSTRACT: Riparian buffers are considered important management options for protecting water quality. Land costs and buffer performance, which are functions of local environmental characteristics, are likely to be key attributes in the selection process, especially when budgets are limited. In this article we demonstrate how a framework involving hydrologic models and binary optimization can be used to find the optimal buffer subject to a budget constraint. Two hydrologic models, SWAT and REMM, were used to predict the loads from different source areas with and without riparian buffers. These loads provided inputs for a binary optimization model to select the most cost efficient parcels to form a riparian buffer. This methodology was applied in a watershed in Delaware County, New York. The models were parameterized using readily available digital databases and were later compared against observed flow and water quality data available for the site. As a result of the application of this method, the marginal utility of incremental increases in buffer widths along the stream channel and the set of parcels to form the best affordable riparian buffer were obtained.  相似文献   
216.
Several hypotheses suggested by the theoretical literature on burnout were empirically tested in an attempt to identify the organizational conditions associated with employee burnout. Public service lawyers in the U.S. (N= 391) completed a survey designed to assess (a) three components of burnout, namely, emotional exhaustion, depersonalization, and feelings of low personal accomplishment; (b) perceptions of several job conditions predicted to be associated these three components of burnout, including workload, role conflict, social support, decision-making policies, and autonomy; and (c) organizational commitment. Results indicate that emotional exhaustion is most strongly associated with role conflict and quantitative workload. Feelings of personal accomplishment were associated with supervisory social support and job level. Depersonalization was associated with role conflict and decision-making policies. Finally, each burnout component is significantly related to organizational commitment.  相似文献   
217.
218.
The Application of IUCN Red List Criteria at Regional Levels   总被引:13,自引:1,他引:12  
This paper represents a work in progress by the World Conservation Union (IUCN). Earlier drafts of the work have appeared in IUCN publications, but the "International Issues" section of Conservation Biology seems an appropriate and important place to publish the penultimate version of the document. Comments on this issue in general or on the approach taken by the IUCN should be sent to the authors directly.
Joshua Ginsburg  相似文献   
219.
Ecosystem services (ES) is a valuable concept to be used in the planning and management of social–ecological landscapes. However, the understanding of the determinant factors affecting the interaction between services in the form of synergies or trade-offs is still limited. We assessed the production of 16 ES across 62 municipalities in the Norrström drainage basin in Sweden. We combined GIS data with publically available information for quantifying and mapping the distribution of services. Additionally, we calculated the diversity of ES for each municipality and used correlations and k-means clustering analyses to assess the existence of ES bundles. We found five distinct types of bundles of ES spatially agglomerated in the landscape that could be explained by regional social and ecological gradients. Human-dominated landscapes were highly multifunctional in our study area and urban densely populated areas were hotspots of cultural services.  相似文献   
220.
Horne JS  Garton EO 《Ecology》2006,87(5):1146-1152
Choosing an appropriate home range model is important for describing space use by animals and understanding the ecological processes affecting animal movement. Traditional approaches for choosing among home range models have not resulted in general, consistent, and unambiguous criteria that can be applied to individual data sets. We present a new application of information-theoretic model selection that overcomes many of the limitations of traditional approaches, as follows. (1) It alleviates the need to know the true home range to assess home range models, thus allowing performance to be evaluated with data on individual animals. (2) The best model can be chosen from a set of candidate models with the proper balance between fit and complexity. (3) If candidate home range models are based on underlying ecological processes, researchers can use the selected model not only to describe the home range, but also to infer the importance of various ecological processes affecting animal movements within the home range.  相似文献   
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