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   79篇
  免费   3篇
安全科学   1篇
废物处理   4篇
环保管理   7篇
综合类   28篇
基础理论   18篇
环境理论   1篇
污染及防治   17篇
评价与监测   2篇
社会与环境   4篇
  2022年   1篇
  2021年   3篇
  2020年   1篇
  2019年   1篇
  2018年   3篇
  2016年   5篇
  2015年   4篇
  2014年   4篇
  2013年   3篇
  2012年   4篇
  2011年   4篇
  2010年   5篇
  2009年   5篇
  2006年   4篇
  2005年   3篇
  2004年   1篇
  2003年   1篇
  2002年   1篇
  2001年   4篇
  1998年   1篇
  1994年   1篇
  1984年   1篇
  1983年   1篇
  1982年   1篇
  1979年   1篇
  1977年   2篇
  1974年   1篇
  1972年   2篇
  1966年   1篇
  1963年   1篇
  1962年   3篇
  1960年   1篇
  1957年   1篇
  1955年   2篇
  1954年   2篇
  1953年   1篇
  1951年   1篇
  1938年   1篇
排序方式: 共有82条查询结果,搜索用时 15 毫秒
61.
62.
Assessing past impacts of observed climate change on natural, human and managed systems requires detailed knowledge about the effects of both climatic and other drivers of change, and their respective interaction. Resulting requirements with regard to system understanding and long-term observational data can be prohibitive for quantitative detection and attribution methods, especially in the case of human systems and in regions with poor monitoring records. To enable a structured examination of past impacts in such cases, we follow the logic of quantitative attribution assessments, however, allowing for qualitative methods and different types of evidence. We demonstrate how multiple lines of evidence can be integrated in support of attribution exercises for human and managed systems. Results show that careful analysis can allow for attribution statements without explicit end-to-end modeling of the whole climate-impact system. However, care must be taken not to overstate or generalize the results and to avoid bias when the analysis is motivated by and limited to observations considered consistent with climate change impacts.  相似文献   
63.
Redevelopment of large contaminated brownfields (megasites) is often hampered by a lack of communication and harmonization among diverse stakeholders with potentially conflicting interests. Decision support is required to provide integrative yet transparent evaluation of often complex spatial information to stakeholders with different areas of expertise. It is considered crucial for successful redevelopment to identify a shared vision of how the respective contaminated site could be remediated and redeveloped. We describe a framework of assessment methods and models that analyzes and visualizes site- and land use-specific spatial information at the screening level, with the aim to support the derivation of recommendable land use layouts and to initiate further and more detailed planning. The framework integrates a GIS-based identification of areas to be remediated, an estimation of associated clean-up costs, a spatially explicit market value appraisal, and an assessment of the planned future land use's contribution to sustainable urban and regional development. Case study results show that derived options are potentially favorable in both a sustainability and an economic sense and that iterative re-planning is facilitated by the evaluation and visualization of economic, ecological and socio-economic aspects. The framework supports an efficient early judgment about whether and how abandoned land may be assigned a sustainable and marketable land use.  相似文献   
64.
Critical loads are widely used in the effects-based assessment of emission reduction policies. While the impacts of acidification have diminished, there is increasing concern regarding the effects of nitrogen deposition on terrestrial ecosystems. In this context much attention has been focussed on empirical critical loads as well as simulations with linked geochemistry-vegetation models. Surprisingly little attention has been paid to adapt the widely used simple mass balance approach. This approach has the well-established benefit of easy regional applicability, while incorporating specified critical chemical criteria to protect specified receptors. As plant occurrence/biodiversity is related to both the nutrient and acidity status of an ecosystem, a single abiotic factor (chemical criterion) is not sufficient. Rather than an upper limit for deposition (i.e., critical load), linked nutrient nitrogen and acidity chemical criteria for plant occurrence result in an ‘optimal’ nitrogen and sulphur deposition envelope.  相似文献   
65.
66.
Formal engagement of indigenous peoples in conservation is increasing globally and leads to multiple benefits to communities while contributing to national and international biodiversity goals and obligations. This and ongoing declines in biodiversity have led to calls to increase opportunities for indigenous people to engage in managing their estates. However, there is no overarching understanding of indigenous peoples’ involvement in conservation, which limits the identification of new opportunities. We amalgamated information across governments and large nongovernmental organizations in the megadiverse country of Australia to quantify the involvement of indigenous people in management of threatened species. We identified 153 Australian‐based projects undertaken by different indigenous groups around the nation in 2015 and 2016 that included explicit funds for management of threatened species or threatened ecosystems. Most were in remote parts of western and northern Australia. Almost one‐quarter of all threatened animals and 2% of threatened plants were the subject of some formal conservation action by indigenous people. Occurrence records for 1574 threatened species showed that 823 (89.2%) of 923 species recorded on indigenous peoples’ lands were not listed in management projects. This gap may represent new opportunities for conservation initiatives. Because at least 59.5% of Australia's threatened species occur on indigenous peoples’ lands, efforts to build appropriate and effective indigenous conservation alliances are vital. However, it is also important to recognize that threatened species are part of complex social, ecological, economic and cultural systems, and to achieve successful outcomes requires consideration of indigenous peoples’ priorities, rights, and obligations and relationships with their traditionally owned land and sea.  相似文献   
67.
68.
While it is developing rapidly throughout Germany, bioenergy provision is open to different development opportunities. To understand the cause–effect relationships that drive bioenergy development and explore different development options and their effects on regional development, qualitative scenarios have been drafted using the Görlitz district as an example. The paper introduces the scenario method, with scenarios that are expressed in storylines. Driving forces and their relationships are thereupon reflected. The results show that the relation of the Common Agricultural Policy and Renewable Energy Act is of particular importance for future development in general. For the specific type of development in particular in rural regions, technologies are equally important, as they allow for both strongly central and highly decentralised developments. Due to an increasing diversity of options, the decision between central and decentral developments is, however, less technologically determined, but rather dependent on stakeholders’ decisions. Such stakeholders not only include stakeholders from the production sector, but also include consumers and affected parties, particularly the inhabitants whose living environment is changing rapidly. Both the landscape and society are subject to change. As a major driving force and an impacted system under change itself, social constellations must be taken into account to ensure a sustainable development under the signs of renewable energy expansion. Management tools should consider the interlinkage between landscape, energy, and social systems.  相似文献   
69.
If agro-ecological systems are to realize their potential as sustainable alternatives to conventional agricultural systems, innovation diffusion needs to be enhanced. We conducted surveys among 214 small-scale vegetable farmers in Benin, a food-deficit country in West Africa, on how they perceived the different attributes of eco-friendly nets (EFNs). The nets act as physical barriers against insects in vegetable production and so reduce pesticide use. Understanding farmer perceptions about new technologies helps reveal farmers’ propensity to adopt them. Intensity of attitude was measured on a Likert scale, and an ordered probit model was used to determine which characteristics of nets were most influential. Eighteen percent of farmers thought that EFNs would benefit them, but almost half preferred not to adopt this technology at all. The main reason for rejecting the nets was the perceived high labor requirement, particularly on larger plots of land. This largely negative perception was strongest among farmers with large areas cultivated with vegetables, farmers who had little or no experience in a trial, and those living far from extension services. We recommend expanded trials that engage a higher proportion of farmers, strengthening of external support for those wanting to use the nets and further technological development to reduce labor costs, improved access to finance and increased education about the negative impacts of insecticides abuse.  相似文献   
70.
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