全文获取类型
收费全文 | 276篇 |
免费 | 17篇 |
国内免费 | 1篇 |
专业分类
安全科学 | 11篇 |
废物处理 | 3篇 |
环保管理 | 96篇 |
综合类 | 17篇 |
基础理论 | 115篇 |
环境理论 | 1篇 |
污染及防治 | 27篇 |
评价与监测 | 12篇 |
社会与环境 | 8篇 |
灾害及防治 | 4篇 |
出版年
2023年 | 4篇 |
2022年 | 5篇 |
2021年 | 6篇 |
2020年 | 9篇 |
2019年 | 4篇 |
2018年 | 6篇 |
2017年 | 8篇 |
2016年 | 8篇 |
2015年 | 10篇 |
2014年 | 5篇 |
2013年 | 13篇 |
2012年 | 11篇 |
2011年 | 7篇 |
2010年 | 10篇 |
2009年 | 9篇 |
2008年 | 7篇 |
2007年 | 16篇 |
2006年 | 11篇 |
2005年 | 9篇 |
2004年 | 4篇 |
2003年 | 11篇 |
2002年 | 6篇 |
2001年 | 3篇 |
2000年 | 5篇 |
1999年 | 2篇 |
1998年 | 8篇 |
1997年 | 6篇 |
1996年 | 6篇 |
1995年 | 5篇 |
1994年 | 8篇 |
1993年 | 2篇 |
1991年 | 4篇 |
1990年 | 3篇 |
1989年 | 12篇 |
1988年 | 7篇 |
1987年 | 6篇 |
1986年 | 3篇 |
1984年 | 4篇 |
1982年 | 5篇 |
1981年 | 5篇 |
1980年 | 3篇 |
1979年 | 2篇 |
1975年 | 2篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1970年 | 1篇 |
1968年 | 1篇 |
1962年 | 1篇 |
1957年 | 3篇 |
1955年 | 2篇 |
排序方式: 共有294条查询结果,搜索用时 15 毫秒
271.
The Nottingham Cycle Friendly Employers Project studied the effectiveness of measures to promote cycling to work by eight large city employers under the 1995 governmentfunded Cycle Challenge. Progress was monitored by 'before' and 'after' surveys, by examination of the measures, and by discussions with the employers. Overall cycling awareness and activity were increased by the project: 42% of employees said their cycle commuting had increased. The main influences, about equally, were providing workplace cycling facilities, a house or job move making cycling more attractive, and heightened awareness of the importance of regular exercise for health. The most welcomed and best used measures were secure cycle parking, showering and changing facilities, and cycle purchase loans. 相似文献
272.
273.
Hugh Lehman E. Ann Clark Stephan F. Weise 《Journal of Agricultural and Environmental Ethics》1993,6(2):127-143
A number of distinct definitions ofsustainable agriculture have been proposed. In this paper we criticize two such definitions, primarily for conflating sustainability with other objectives such as economic viability and ecological integrity. Finally, we propose and defend a definition which avoids our objections to the other definitions. 相似文献
274.
Hugh Clout 《Journal of Environmental Planning and Management》1989,32(1):23-34
Reims was in the direct line of fire throughout the First World War and suffered almost complete destruction. Planning for reconstruction proved controversial and grand designs were only implemented in part, with the help of government funds, important reconstruction cooperatives and American aid. The new Reims involved additional and wider thoroughfares, an enormous array of new public and private buildings in the city centre, and almost a dozen highly distinctive garden suburbs, built by private and municipal housing authorities. By 1926 the city had virtually regained its 1911 population level, but painstaking reconstruction of many historic buildings was not to be completed until well into the 1930s. The architectural legacy of the interwar period, especially that of the Art Deco movement, has been analysed thoroughly and appreciated more positively in recent years. 相似文献
275.
276.
277.
WICKED WATER PROBLEMS: SOCIOLOGY AND LOCAL WATER ORGANIZATIONS IN ADDRESSING WATER RESOURCES POLICY1
David M. Freeman 《Journal of the American Water Resources Association》2000,36(3):483-491
ABSTRACT: Water policy problems are wicked, not in an ethically deplorable sense, but in the sense that they present us with especially difficult challenges of becoming more effective in our interdisciplinary collaboration, of integrating two very different types of knowledge, of working across several socio‐political units of analysis simultaneously, and of better organizing water as a common property resource. Sociology, as a discipline, does not have a particularly rich history of successful interdisciplinary collaboration on water resources research and teaching, but it potentially has a most useful contribution to make by focusing on the analysis of local common property resource organizations that operate in the interface between individual resource users and State‐Federal entities. These organizations (e.g., water user associations, mutual companies, irrigation districts, acequias, conservancy districts) have been the orphans of water policy discourse but their operations are critical to undertaking more effective 21st century social analysis, research work, and action programs. Sociologists who work to better comprehend the operations of, and constraints upon, these organizations build a sociology that can better collaborate with other water‐related disciplines in addressing the challenges posed by the wickedness of our water problems. 相似文献
278.
Edward T Game Matthew E Watts Scott Wooldridge Hugh P Possingham 《Ecological applications》2008,18(3):670-680
Large-scale catastrophic events, although rare, lie generally beyond the control of local management and can prevent marine reserves from achieving biodiversity outcomes. We formulate a new conservation planning problem that aims to minimize the probability of missing conservation targets as a result of catastrophic events. To illustrate this approach we formulate and solve the problem of minimizing the impact of large-scale coral bleaching events on a reserve system for the Great Barrier Reef, Australia. We show that by considering the threat of catastrophic events as part of the reserve design problem it is possible to substantially improve the likely persistence of conservation features within reserve networks for a negligible increase in cost. In the case of the Great Barrier Reef, a 2% increase in overall reserve cost was enough to improve the long-run performance of our reserve network by >60%. Our results also demonstrate that simply aiming to protect the reefs at lowest risk of catastrophic bleaching does not necessarily lead to the best conservation outcomes, and enormous gains in overall persistence can be made by removing the requirement to represent all bioregions in the reserve network. We provide an explicit and well-defined method that allows the probability of catastrophic disturbances to be included in the site selection problem without creating additional conservation targets or imposing arbitrary presence/absence thresholds on existing data. This research has implications for reserve design in a changing climate. 相似文献
279.
Hugh Lehman 《Journal of Agricultural and Environmental Ethics》2000,12(3):305-317
Some writers have suggested that it would be desirable to assess the state of the Earth'senvironments by making use of a concept of ecosystem health. We subject this suggestion toscrutiny first by calling attention to obscurities inthe notion of an ecosystem and then by callingattention to obscurities in and objections to someviews about ecosystem health. Finally, we note, thateven if ecosystem health can be adequately clarified, there are reasons for saying that whetherwe are morally obligated to protect the health ofsome ecosystem depends on other circumstances. In many possible circumstances we would not beobligated to protect the health of a particularecosystem. 相似文献
280.
We develop regional-scale eutrophication models for lakes, ponds, and reservoirs to investigate the link between nutrients and chlorophyll-a. The Bayesian TREED (BTREED) model approach allows association of multiple environmental stressors with biological responses, and quantification of uncertainty sources in the empirical water quality model. Nutrient data for lakes, ponds, and reservoirs across the United States were obtained from the Environmental Protection Agency (EPA) National Nutrient Criteria Database. The nutrient data consist of measurements for both stressor variables (such as total nitrogen and total phosphorus), and response variables (such as chlorophyll-a), used in the BTREED model. Markov chain Monte Carlo (McMC) posterior exploration guides a stochastic search through a rich suite of candidate trees toward models that better fit the data. The Bayes factor provides a goodness of fit criterion for comparison of resultant models. We randomly split the data into training and test sets; the training data were used in model estimation, and the test data were used to evaluate out-of-sample predictive performance of the model. An average relative efficiency of 1.02 between the training and test data for the four highest log-likelihood models suggests good out-of-sample predictive performance. Reduced model uncertainty relative to over-parameterized alternative models makes the BTREED models useful for nutrient criteria development, providing the link between nutrient stressors and meaningful eutrophication response. 相似文献