全文获取类型
收费全文 | 99篇 |
免费 | 3篇 |
国内免费 | 1篇 |
专业分类
安全科学 | 6篇 |
环保管理 | 33篇 |
综合类 | 38篇 |
基础理论 | 11篇 |
污染及防治 | 9篇 |
评价与监测 | 2篇 |
社会与环境 | 4篇 |
出版年
2019年 | 4篇 |
2018年 | 2篇 |
2015年 | 1篇 |
2014年 | 1篇 |
2013年 | 2篇 |
2012年 | 1篇 |
2011年 | 5篇 |
2010年 | 1篇 |
2009年 | 2篇 |
2008年 | 1篇 |
2007年 | 2篇 |
2006年 | 3篇 |
2005年 | 6篇 |
2004年 | 1篇 |
2003年 | 3篇 |
2002年 | 1篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 3篇 |
1993年 | 1篇 |
1991年 | 4篇 |
1988年 | 2篇 |
1987年 | 7篇 |
1986年 | 1篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1980年 | 1篇 |
1970年 | 1篇 |
1969年 | 2篇 |
1968年 | 5篇 |
1967年 | 3篇 |
1965年 | 1篇 |
1962年 | 1篇 |
1959年 | 1篇 |
1957年 | 2篇 |
1956年 | 1篇 |
1955年 | 3篇 |
1954年 | 4篇 |
1953年 | 2篇 |
1952年 | 1篇 |
1951年 | 1篇 |
1942年 | 2篇 |
1938年 | 1篇 |
1935年 | 1篇 |
1930年 | 1篇 |
1929年 | 1篇 |
排序方式: 共有103条查询结果,搜索用时 0 毫秒
1.
2.
3.
4.
F. Steiner 《Die Naturwissenschaften》1935,23(26-28):489-490
5.
6.
Agricultural land evaluation and site assessment in the United States: An introduction 总被引:2,自引:0,他引:2
Frederick Steiner 《Environmental management》1987,11(3):375-377
The US Soil Conservation Service has developed an agricultural land evaluation and site assessment (LESA) system. The LESA system is being used by the US Department of Agriculture and other federal agencies to implement the Farmland Protection Policy Act of 1981. The LESA system and three case studies from the Pacific North-west are introduced in this article.Scientific Paper no. 7166, College of Agriculture and Home Economics Research Paper. Washington State University, Pullman, Washington. Project no. 0010. 相似文献
7.
9.
10.
Lee JC Skelly JM Steiner KC Zhang JW Savage JE 《Environmental pollution (Barking, Essex : 1987)》1999,105(3):325-331
During late summer of 1996 and 1997 we examined ozone-induced foliar injury in a plantation of 111 black cherry trees (ramets) comprising 15 clones originating from wild ortets growing in the Allegheny National Forest, Pennsylvania, and the Monongahela National Forest, West Virginia. The experimental plantation was a clonal seed orchard in Centre County, Pennsylvania, started in 1971 using ortet buds grafted onto seedling rootstocks of mixed origin. Clones differed significantly in severity of foliar injury symptoms (F=31.83, p<0.001). One clone (R-12) had significantly more foliar injury with >50% leaf area affected than other clones during both years. In contrast, clone R-14, which is from the same area in northcentral Pennsylvania as R-12, exhibited significantly less injury (LAA<6%). Although ambient O(3) concentrations were similar in both years, foliar injury was significantly greater (15.7%) in 1996 than in 1997 (9.9%). This is probably explained by lower stomatal conductance in 1997 caused by drier and hotter weather patterns in June and July of that year. Despite very different weather patterns and overall levels of injury in 1996 and 1997, mean clonal injury was significantly correlated between both years of assessment (r=0.92, p<0.001). Within tree crowns, foliage in lower and inner crown positions was significantly more injured than foliage in upper and exterior crown positions. There was no evidence of geographically based population differences in sensitivity to foliar O(3) injury. On the contrary, results demonstrate that wild genotypes of proximal geographic origin may differ greatly in sensitivity. 相似文献