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   26410篇
  免费   183篇
  国内免费   135篇
安全科学   399篇
废物处理   1480篇
环保管理   3183篇
综合类   3547篇
基础理论   7765篇
环境理论   4篇
污染及防治   5809篇
评价与监测   2082篇
社会与环境   2358篇
灾害及防治   101篇
  2022年   140篇
  2021年   117篇
  2020年   118篇
  2019年   120篇
  2018年   1735篇
  2017年   1677篇
  2016年   1540篇
  2015年   404篇
  2014年   488篇
  2013年   1243篇
  2012年   980篇
  2011年   2099篇
  2010年   1409篇
  2009年   1258篇
  2008年   1659篇
  2007年   2083篇
  2006年   612篇
  2005年   618篇
  2004年   580篇
  2003年   656篇
  2002年   673篇
  2001年   675篇
  2000年   497篇
  1999年   269篇
  1998年   201篇
  1997年   213篇
  1996年   208篇
  1995年   243篇
  1994年   239篇
  1993年   184篇
  1992年   199篇
  1991年   185篇
  1990年   207篇
  1989年   191篇
  1988年   152篇
  1987年   165篇
  1986年   154篇
  1985年   157篇
  1984年   166篇
  1983年   153篇
  1982年   128篇
  1981年   120篇
  1980年   118篇
  1979年   126篇
  1978年   100篇
  1977年   114篇
  1975年   87篇
  1974年   87篇
  1973年   96篇
  1972年   86篇
排序方式: 共有10000条查询结果,搜索用时 359 毫秒
241.
242.
Mitigation and adaptation synergy in forest sector   总被引:1,自引:1,他引:1  
Mitigation and adaptation are the two main strategies to address climate change. Mitigation and adaptation have been considered separately in the global negotiations as well as literature. There is a realization on the need to explore and promote synergy between mitigation and adaptation while addressing climate change. In this paper, an attempt is made to explore the synergy between mitigation and adaptation by considering forest sector, which on the one hand is projected to be adversely impacted under the projected climate change scenarios and on the other provide opportunities to mitigate climate change. Thus, the potential and need for incorporating adaptation strategies and practices in mitigation projects is presented with a few examples. Firstly, there is a need to ensure that mitigation programs or projects do not increase the vulnerability of forest ecosystems and plantations. Secondly, several adaptation practices could be incorporated into mitigation projects to reduce vulnerability. Further, many of the mitigation projects indeed reduce vulnerability and promote adaptation, for example; forest and biodiversity conservation, protected area management and sustainable forestry. Also, many adaptation options such as urban forestry, soil and water conservation and drought resistant varieties also contribute to mitigation of climate change. Thus, there is need for research and field demonstration of synergy between mitigation and adaptation, so that the cost of addressing climate change impacts can be reduced and co-benefits increased.  相似文献   
243.
In 1964, Walter Rothenbuhler proposed a two-gene model to explain phenotypic variance in the remarkable behavior in which honey bee workers remove dead brood from their colonies. Rothenbuhler's model proposed that one locus controls the uncapping of brood cells containing dead pupae, while a second controls the removal of the cell contents. We show here, through molecular techniques and quantitative trait loci (QTL) linkage mapping, that the genetic basis of hygienic behavior is more complex, and that many genes are likely to contribute to the behavior. In our cross, we detected seven suggestive QTLs associated with hygienic behavior. Each detected QTL controlled only 9-15% of the observed phenotypic variance in the character.  相似文献   
244.
The possible effects of landscape structure on starling roost distribution were investigated in western France using GIS analysis at different radii (2, 4, 8 and 10 km). Composition (11 land use classes) and configuration (patch size, diversity index) of the landscapes surrounding 97 roost sites used by starlings from 1981 to 2002 and surrounding 50 random points not used as roost sites were compared. Significant results suggested that starling roosts were established preferentially in the centre of an agricultural landscape where large units of pastures and arable land predominated and where natural areas were lacking both in large patches (forests or wetland classes) and in small patches such as woods in the mixed land class. A varied farmland landscape with natural areas and small patches should be promoted to limit the starling damage in wintering regions and also to favour their reproduction in regions where it has declined.  相似文献   
245.
246.
247.
248.
Haase-Wessel  W.  Ohmasa  M.  Süsse  P. 《Die Naturwissenschaften》1977,64(8):435-435
The Science of Nature -  相似文献   
249.
Hurler's disease was excluded in a fetus at 23 weeks' gestation by demonstrating normal iduronidase activity in fetal leucocytes following failure of amniotic cell culture after amnic-centesis at 16 and 19 weeks' gestation. The diagnosis was confirmed in the neonate.  相似文献   
250.
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