首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   268篇
  免费   4篇
  国内免费   7篇
废物处理   1篇
环保管理   97篇
综合类   62篇
基础理论   47篇
污染及防治   53篇
评价与监测   13篇
社会与环境   6篇
  2023年   4篇
  2022年   10篇
  2021年   17篇
  2019年   1篇
  2018年   2篇
  2017年   11篇
  2016年   15篇
  2015年   19篇
  2014年   8篇
  2013年   12篇
  2012年   8篇
  2011年   22篇
  2010年   7篇
  2009年   20篇
  2008年   18篇
  2007年   18篇
  2006年   8篇
  2005年   4篇
  2004年   9篇
  2003年   5篇
  2002年   7篇
  2001年   1篇
  2000年   14篇
  1999年   4篇
  1998年   3篇
  1997年   2篇
  1996年   16篇
  1995年   7篇
  1994年   3篇
  1993年   1篇
  1992年   1篇
  1988年   2篇
排序方式: 共有279条查询结果,搜索用时 31 毫秒
121.
Biodiversity policies in the European Union (EU) are mainly implemented through the Birds and Habitats Directives as well as the establishment of Natura 2000, a network of protected areas throughout the EU. Considerable resources must be allocated for fulfilling the Directives and the question of optimal allocation is as important as it is difficult. In general, economic evaluations of conservation targets at most consider the costs and seldom the welfare economic benefits. In the present study, we use welfare economic benefit estimates concerning the willingness-to-pay for preserving endangered species and for the aggregate area of heathland preserved in Denmark. Similarly, we obtain estimates of the welfare economic cost of habitat restoration and maintenance. Combining these welfare economic measures with expected species coverage, we are able to estimate the potential welfare economic contribution of a conservation network. We compare three simple nonprobabilistic strategies likely to be used in day-to-day policy implementation: i) a maximum selected area strategy, ii) a hotspot selection strategy, and iii) a minimizing cost strategy, and two more advanced and informed probabilistic strategies: i) a maximum expected coverage strategy and ii) a strategy for maximum expected welfare economic gain. We show that the welfare economic performance of the strategies differ considerably. The comparison between the expected coverage and expected welfare shows that for the case considered, one may identify an optimal protection level above which additional coverage only comes at increasing welfare economic loss.  相似文献   
122.
This paper develops a comprehensive and objective picture of bird distributions relative to habitats across Britain. Bird species presence/absence data from an extensive field survey and habitat data from the remotely sensed UK Land Cover Map 2000 were analysed in 36,920 tetrads (2 kmx2 km) across Britain (a 65% sample of Britain's c. 240,000 km2). Cluster analysis linked birds to generalised landscapes based on distinctive habitat assemblages. Maps of the clusters showed strong regional patterns associated with the habitat assemblages. Cluster centroid coordinates for each bird species and each habitat were combined across clusters to derive individualised bird-habitat preference indices and examine the importance of individual habitats for each bird species. Even rare species and scarce habitats showed successful linkages. Results were assessed against published accounts of bird-habitat relations. Objective corroboration strongly supported the associations. Relatively scarce coastal and wetland habitats proved particularly important for many birds. However, extensive arable farmland and woodland habitats were also favoured by many species, despite reported declines in bird numbers in these habitats. The fact that habitat-specialists do not or cannot move habitat is perhaps a reason for declining numbers where habitats have become unsuitable. This study showed that there are unifying principles determining bird-habitat relations which apply and can be quantified at the national scale, and which corroborate and complement the cumulative knowledge of many and varied surveys and ecological studies. This 'generality' suggests that we may be able, reliably and objectively, to integrate and scale up such disparate studies to the national scale, using this generalised framework. It also suggests the potential for a landscape ecology approach to bird-habitat analyses. Such developments will be important steps in building models to develop and test the sustainable management of landscapes for birds.  相似文献   
123.
Ecosystem services provided by the landscapes of regions and cities are critical to human and environmental health, quality of life, environmental justice, biodiversity and climate mitigation and adaptation. In the Pacific Northwest region of the US, a team led by the University of Washington Green Futures Lab is working to identify, conserve and enhance regionally-significant landscapes and to evaluate their contributions as ecosystem or “open space” services. This paper outlines the goals and planning methods of the ongoing Regional Open Space Strategy for Central Puget Sound (ROSS) project, and the frameworks and processes being developed to evaluate ecosystem and open space services in order to inform and influence local and regional governance structures and decisions.  相似文献   
124.
This paper uses GIS-based mapping tools and economic valuation of ecosystem goods and services to explore the social dimension of biodiversity policy. We investigate the linkages between biodiversity, ecosystem service values, and socio-economic vulnerability indicators in a spatially explicit framework and at different geographic scales. Our focus is on Europe, where biodiversity and ecosystem benefits have been well studied for many ecosystems, such as forests, coastal ecosystems and freshwater wetlands. The analysis focuses in particular on rural agricultural areas and remote mountainous regions accounting for the differences across various income groups, both at national and regional levels. The results of the study provide useful insights for EU policymakers in designing policy instruments that can promote biodiversity conservation and prevent natural resource degradation, on the one hand, while contributing to social stability and human livelihoods, on the other hand.  相似文献   
125.
Market-based instruments along with conceptualizing the environment as a collection of ‘ecosystem services’ has become increasingly common within environmental and conservation policy. This kind of thinking is also increasingly prominent in the public discourse surrounding environment and conservation policy, particularly in the context of communicating the importance of policy measures. Language used in public discourse can have a powerful influence on how people engage with policy issues, and changes within the biodiversity and conservation discourse may have consequences for public engagement in conservation. We explored how these factors are changing with time by documenting the use of the terms ‘bio’ and the prevalence of economic language in the text of 3553 media releases between 2003 and 2014 from the Australian Government environment portfolio, and 1064 media releases from the Australian Conservation Foundation (ACF). Results show that in the last decade, the term ‘biodiversity’ has become less prevalent whilst economic language has increased in both Australian Government and ACF communication. A further content analysis in a subsample of 745 media releases explored the prevalence of ecosystem services framing, results indicating that it has become a mainstream concept. While this may reflect a strategic response by these agencies to better engage with both the general public and decision makers within what is an increasingly dominant neoliberal paradigm, we argue it may also have unintended (possibly adverse) impacts on how people think about and engage with biodiversity conservation.  相似文献   
126.
The aim of this study was to assess spider diversity among habitats that are typically used for afforestation in Ireland, and to identify habitat parameters which could potentially be used as indicators of their biodiversity value. Ground-dwelling spiders were surveyed in 24 sites across Ireland, with eight sites of each of the following habitat types: improved grassland, wet grassland and peatland. The spiders were sampled using pitfall traps which were located within the major vegetation types present in each site as well as within supplementary habitat features which may add to biodiversity value of the whole site such as hedgerows, flushes and the edges of ditches and streams.Each habitat supported distinct spider assemblages that reflect major differences in both environmental conditions and management regime. The improved grasslands had low spider species richness and low variation in assemblage structure which is probably related to the intensive management of this habitat. In this case hedgerows maybe an important aspect of the spider diversity within agricultural landscapes. The peatlands, and to a lesser extent wet grasslands, supported a diverse and specialist spider fauna, including a number of rare species; this may be due to differences in soil moisture and plant architecture. Indicators of biodiversity value identified included wet flushes in the peatlands and low grazing pressure in the wet grasslands. This study suggests that in terms of biodiversity value improved grassland is the preferable habitat for afforestation, because of the poor baseline spider diversity. However, it may be unrealistic to expect land owners to afforest their most productive agricultural land, so the management and habitat indicators identified in this study may be of use for assessing habitat quality among the wet grassland and peatlands to allow sites with lower biodiversity value to be identified.  相似文献   
127.
对铁岭凡河8个样点进行了大型底栖无脊椎动物多样性调查研究,共发现类群3门6纲11目28科63属75种。按照BI指数进行评价结果:孤家子、腰寨子、榛子岭水库入口、抚安堡、张搂子样点水体最清洁至清洁;新屯大桥样点清洁至轻污染;榛子岭水库出口、黄河子样点轻污染至中污染。  相似文献   
128.
监测分析云龙湖底栖动物种类变化、密度变化,底质组成与变化及生物多样性指数的变化来研究云龙湖水质的变化趋势。研究表明:近5年,云龙湖东湖水质有所改善,西湖富营养化有加重趋势。  相似文献   
129.
Tropical montane cloud forests (TMCF) are among the most threatened ecosystems globally in spite of their high strategic value for sustainable development due to the key role played by these forests in hydrological cycle maintenance and as reservoirs of endemic biodiversity. Resources for effective conservation and management programs are rarely sufficient, and criteria must be applied to prioritize TMCF for conservation action. This paper reports a priority analysis of the 13 main regions of TMCF distribution in Mexico, based on four criteria: (1) forest quality, (2) threats to forest permanence, (3) threats to forest integrity, and (4) opportunities for conservation. Due to the diverse socio-environmental conditions of the local communities living in Mexican TMCF regions, their associated social characteristics were also evaluated to provide a background for the planning of conservation actions. A set of indicators was defined for the measurement of each criterion. To assign priority values for subregions within each main region, an international team of 40 participants evaluated all the indicators using multicriteria decision-making analysis. This procedure enabled the identification of 15 subregions of critical priority, 17 of high priority, and 10 of medium priority; three more were not analysed due to lack of information. The evaluation revealed a number of subjects that had hitherto been undetected and that may prove useful for prioritization efforts in other regions where TMCF is similarly documented and faces equally severe threats. Based on this analysis, key recommendations are outlined to advance conservation objectives in those TMCF areas that are subjected to high pressure on forest resources.  相似文献   
130.
Despite a growing body of literature on public views on biodiversity and nature, our understanding of public attitudes towards animal and plant species is still rudimentary. This study investigates mental representations, constituted by beliefs, of three types of species (a large mammal, a spider and a non-native plant), and explores their links with cultural factors such as value orientations and cultural capital, in order to better understand attitudes towards these species.We conducted a survey in eight sites across Europe (n = 2378) and found strong relationships between beliefs about species, in particular with regard to their harmlessness, value and previous population change, and the desirability of an increase in this species. Other beliefs, such as perceived nativeness, were less influential. We discuss how respondents combined beliefs to mental representations of species, and show how representations are related to species-independent factors that tap respondents’ cultural context, such as socially shared value orientations and education.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号