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   2078篇
  免费   34篇
  国内免费   15篇
安全科学   69篇
废物处理   74篇
环保管理   378篇
综合类   336篇
基础理论   483篇
环境理论   4篇
污染及防治   529篇
评价与监测   151篇
社会与环境   91篇
灾害及防治   12篇
  2023年   22篇
  2022年   23篇
  2021年   28篇
  2020年   25篇
  2019年   30篇
  2018年   41篇
  2017年   55篇
  2016年   50篇
  2015年   53篇
  2014年   56篇
  2013年   155篇
  2012年   80篇
  2011年   122篇
  2010年   85篇
  2009年   99篇
  2008年   109篇
  2007年   131篇
  2006年   94篇
  2005年   81篇
  2004年   81篇
  2003年   77篇
  2002年   83篇
  2001年   42篇
  2000年   34篇
  1999年   28篇
  1998年   28篇
  1997年   27篇
  1996年   22篇
  1995年   27篇
  1994年   26篇
  1993年   13篇
  1992年   17篇
  1991年   18篇
  1990年   14篇
  1989年   17篇
  1988年   18篇
  1987年   14篇
  1986年   18篇
  1985年   9篇
  1984年   11篇
  1983年   11篇
  1982年   12篇
  1981年   9篇
  1980年   8篇
  1979年   14篇
  1978年   8篇
  1977年   9篇
  1975年   8篇
  1974年   8篇
  1954年   8篇
排序方式: 共有2127条查询结果,搜索用时 417 毫秒
21.
22.
23.
The relationship between land-use induced changes in production ecology and avifauna diversity was analysed using a GIS land cover dataset on a 0.25 km × 0.25 km grid covering Austria's national territory. Considering only aboveground processes, the “human appropriation of net primary production” (HANPP = potential NPP − NPPt), actual NPP (NPPact), harvest (NPPh) and NPPt (= NPPact − harvest) were recalculated based on existing datasets. Elevation as well as indicators of land cover heterogeneity and landscape heterogeneity were also considered. Correlation analyses were performed between these potential determinants of avifauna diversity and breeding bird species richness data as well as the percentage of endangered breeding birds included in the Austrian red list. Four spatial scales—0.25 km × 0.25 km, 1 km × 1 km, 4 km × 4 km and 16 × 16 km, were analysed. It was shown that breeding bird species richness was more strongly correlated with production ecological indicators and elevation than with heterogeneity indicators. A residual analysis in which the effect of elevation (a proxy for climate) on species richness and its potential determinants was removed confirmed the importance of the availability of trophic energy (NPP) for bird diversity patterns. The results support the species-energy hypothesis, thus confirming the notion that HANPP could be a useful pressure indicator for biodiversity loss.  相似文献   
24.
25.
26.
27.
28.
29.
In situ chemical fixation represents a promising and potentially cost‐effective treatment alternative for metal‐contaminated soils. This article presents the findings of the use of iron‐bearing soil amendments to reduce the leachability and bioaccessibility of arsenic in soils impacted by stack fallout from a zinc smelter. The focus of this investigation was to reduce the lead bioaccessibility of the soils through addition with phosphorus‐bearing amendments. However, as phosphorus addition was expected to increase arsenic mobility, the fixation strategy also incorporated use of iron‐bearing amendments to offset or reverse these effects. The findings of this investigation demonstrated that inclusion of iron‐bearing chemicals in the amendment formulation reduced arsenic leachability and bioaccessibility without compromising amendment effectiveness for reducing lead bioaccessibility. These results suggest that in situ chemical fixation has the potential to be an effective strategy for treatment of the impacted soils. © 2003 Wiley Periodicals, Inc.  相似文献   
30.
Water disputes in the Middle East are not a new phenomenon. For the first time, however, three parties in the region, Jordan, Israel, and the PLO for the benefit of the Palestinian Authority have concluded a "regional water agreement" within the framework of the Multilateral Peace talks. For the first time, the rationale behind the agreement is being made public by the author, who was the "neutral" facilitator of the negotiations. The article discusses some of the main elements, including issues related to water scarcity as a driving force of conflicts; application of a "track-two diplomatic" approach; some lessons learned; as well as some ethical questions related to international negotiation.  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