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   22篇
  免费   1篇
安全科学   5篇
环保管理   1篇
综合类   3篇
基础理论   7篇
污染及防治   6篇
社会与环境   1篇
  2023年   1篇
  2018年   1篇
  2015年   2篇
  2012年   2篇
  2011年   1篇
  2010年   3篇
  2009年   2篇
  2008年   1篇
  2007年   2篇
  2006年   1篇
  2000年   1篇
  1998年   1篇
  1996年   1篇
  1991年   1篇
  1987年   1篇
  1982年   1篇
  1978年   1篇
排序方式: 共有23条查询结果,搜索用时 15 毫秒
21.
Species persistence in human‐altered landscapes can depend on factors operating at multiple spatial scales. To understand anthropogenic impacts on biodiversity, it is useful to examine relationships between species traits and their responses to land‐use change. A key knowledge gap concerns whether these relationships vary depending on the scale of response under consideration. We examined how local‐ and large‐scale habitat variables influence the occupancy dynamics of a bird community in cloud forest zones in the Colombian Chocó‐Andes. Using data collected across a continuum of forest and agriculture, we examined which traits best predict species responses to local variation in farmland and which traits best predict species responses to isolation from contiguous forest. Global range size was a strong predictor of species responses to agriculture at both scales; widespread species were less likely to decline as local habitat cover decreased and as distance from forest increased. Habitat specialization was a strong predictor of species responses only at the local scale. Open‐habitat species were particularly likely to increase as pasture increased, but they were relatively insensitive to variation in distance to forest. Foraging plasticity and flocking behavior were strong predictors of species responses to distance from forest, but not their responses to local habitat. Species with lower plasticity in foraging behaviors and obligate flock‐following species were more likely to decline as distance from contiguous forest increased. For species exhibiting these latter traits, persistence in tropical landscapes may depend on the protection of larger contiguous blocks of forest, rather than the integration of smaller‐scale woodland areas within farmland. Species listed as threatened or near threatened on the International Union for Conservation of Nature Red List were also more likely to decline in response to both local habitat quality and isolation from forest relative to least‐concern species, underlining the importance of contiguous forests for threatened taxa.  相似文献   
22.
The core aim of the present study is to examine cultural differences in risk perception and attitudes towards traffic safety and risk, taking behaviour in the Norwegian and the Ghanaian public. An additional aim is to discuss the applicability of various traffic measures, suited for low and middle income countries in Africa.Sample: The results of the present study are based on two self-completion questionnaire surveys carried out in February and March 2006. The first was a representative sample of the Norwegian public above 18 years of age (N = 247). The second was a stratified sample of Ghanaian respondents (N = 299). In Ghana the data was collected in Accra and Cape Coast.The results showed that there is potential for further improvement of safety attitudes and risk behaviour among Ghanaians as well as Norwegians. There were also differences in the respondents’ evaluation of attitudes, risk perception and behaviour. Perceived risk and attitudes also significantly predicted risk behaviour and accidents/collisions. The implications of these results for traffic safety will be discussed.  相似文献   
23.
Investigations of polluted brownfield sites and sample analyses are expensive, and the resulting data are often of poor quality. Efforts are needed, therefore, to improve the methods used in investigations of brownfield sites to both reduce costs and improve the quality of the results. One approach that could be useful for both of these purposes is the triad strategy, developed by the US Environmental Protection Agency, in which managing uncertainty is a central feature. In the investigations reported here, a field study was conducted to identify possible ways in which uncertainties could be managed in practice. One example considered involves optimizing the uncertainty by adjusting the sizes of samples and the efforts expended in analytical work according to the specific aims of the project. In addition, the potential utility of several toxicity assessment methods for screening sites was evaluated. As well as presenting the results of these assessments, in this contribution we discuss ways in which a flexible work strategy and screening methods inspired of the triad philosophy could be incorporated into the Swedish approach to remediate brownfield sites. A tiered approach taking advantage of field and screening methods is proposed to assess brownfield sites focusing on the response and acceptable uncertainty that are required for the task.  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