全文获取类型
收费全文 | 540篇 |
免费 | 3篇 |
国内免费 | 3篇 |
专业分类
安全科学 | 16篇 |
废物处理 | 15篇 |
环保管理 | 64篇 |
综合类 | 295篇 |
基础理论 | 48篇 |
污染及防治 | 84篇 |
评价与监测 | 16篇 |
社会与环境 | 8篇 |
出版年
2021年 | 5篇 |
2018年 | 6篇 |
2017年 | 7篇 |
2015年 | 15篇 |
2014年 | 11篇 |
2013年 | 18篇 |
2012年 | 9篇 |
2011年 | 14篇 |
2010年 | 17篇 |
2009年 | 15篇 |
2008年 | 15篇 |
2007年 | 19篇 |
2006年 | 17篇 |
2005年 | 21篇 |
2004年 | 10篇 |
2003年 | 13篇 |
2002年 | 11篇 |
2001年 | 5篇 |
2000年 | 6篇 |
1999年 | 11篇 |
1995年 | 7篇 |
1984年 | 5篇 |
1967年 | 7篇 |
1966年 | 6篇 |
1965年 | 5篇 |
1963年 | 9篇 |
1962年 | 4篇 |
1961年 | 7篇 |
1959年 | 6篇 |
1958年 | 8篇 |
1957年 | 5篇 |
1956年 | 10篇 |
1955年 | 12篇 |
1954年 | 10篇 |
1947年 | 4篇 |
1942年 | 4篇 |
1939年 | 10篇 |
1938年 | 8篇 |
1937年 | 5篇 |
1936年 | 4篇 |
1934年 | 4篇 |
1933年 | 6篇 |
1932年 | 6篇 |
1929年 | 5篇 |
1928年 | 4篇 |
1927年 | 4篇 |
1926年 | 5篇 |
1925年 | 4篇 |
1914年 | 5篇 |
1913年 | 4篇 |
排序方式: 共有546条查询结果,搜索用时 31 毫秒
301.
Moir ML Vesk PA Brennan KE Poulin R Hughes L Keith DA McCarthy MA Coates DJ 《Conservation biology》2012,26(2):199-207
Translocation, introduction, reintroduction, and assisted migrations are species conservation strategies that are attracting increasing attention, especially in the face of climate change. However, preventing the extinction of the suite of dependent species whose host species are threatened is seldom considered, and the effects on dependent species of moving threatened hosts are unclear. There is no published guidance on how to decide whether to move species, given this uncertainty. We examined the dependent-host system of 4 disparate taxonomic groups: insects on the feather-leaf banksia (Banksia brownii), montane banksia (B. montana), and Stirling Range beard heath (Leucopogon gnaphalioides); parasites of wild cats; mites and ticks on Duvaucel's gecko (Hoplodactylus duvaucelii) and tuatara (Sphenodon punctatus); and internal coccidian parasites of Cirl Bunting (Emberiza cirlus) and Hihi (Notiomystis cincta). We used these case studies to demonstrate a simple process for use in species- and community-level assessments of efforts to conserve dependents with their hosts. The insects dependent on Stirling Range beard heath and parasites on tigers (Panthera tigris) appeared to represent assemblages that would not be conserved by ex situ host conservation. In contrast, for the cases of dependent species we examined involving a single dependent species (internal parasites of birds and the mite Geckobia naultina on Duvaucel's gecko), ex situ conservation of the host species would also conserve the dependent species. However, moving dependent species with their hosts may be insufficient to maintain viable populations of the dependent species, and additional conservation strategies such as supplementing populations may be needed. 相似文献
302.
303.
304.
305.
306.
Ming T. Lee Karl L. Guntermann 《Journal of the American Water Resources Association》1976,12(3):561-576
ABSTRACT This paper reports on research to develop a methodology for estimating agricultural off-site sediment damage costs and includes an empirical estimate of such damages for a watershed. The economics of off-site sediment damage costs are discussed as a theoretical basis for the procedures developed. A detailed methodology is described for estimating five different types of off-site sediment damages commonly associated with rural watersheds. The methodology is then applied to a central Illinois watershed and estimates of individual types of damage are made. The estimates are combined into an off-site sediment damage function for the watershed, and the usefulness of the damage function for analyzing off-site sediment damages and achieving a reduction in those costs is discussed. 相似文献
307.
308.
309.
310.