全文获取类型
收费全文 | 173篇 |
免费 | 6篇 |
国内免费 | 3篇 |
专业分类
安全科学 | 9篇 |
废物处理 | 4篇 |
环保管理 | 53篇 |
综合类 | 44篇 |
基础理论 | 38篇 |
环境理论 | 2篇 |
污染及防治 | 24篇 |
评价与监测 | 5篇 |
社会与环境 | 2篇 |
灾害及防治 | 1篇 |
出版年
2022年 | 5篇 |
2021年 | 3篇 |
2020年 | 10篇 |
2019年 | 6篇 |
2018年 | 2篇 |
2017年 | 10篇 |
2016年 | 11篇 |
2015年 | 2篇 |
2014年 | 5篇 |
2013年 | 20篇 |
2012年 | 8篇 |
2011年 | 11篇 |
2010年 | 4篇 |
2009年 | 3篇 |
2008年 | 6篇 |
2007年 | 6篇 |
2004年 | 3篇 |
2003年 | 3篇 |
2002年 | 3篇 |
2001年 | 4篇 |
1999年 | 4篇 |
1996年 | 2篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1988年 | 2篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1972年 | 1篇 |
1966年 | 2篇 |
1961年 | 1篇 |
1954年 | 1篇 |
1953年 | 1篇 |
1946年 | 1篇 |
1942年 | 1篇 |
1940年 | 1篇 |
1938年 | 2篇 |
1937年 | 3篇 |
1936年 | 1篇 |
1935年 | 1篇 |
1934年 | 2篇 |
1933年 | 2篇 |
1931年 | 2篇 |
1930年 | 1篇 |
1929年 | 3篇 |
1928年 | 2篇 |
1927年 | 1篇 |
1926年 | 1篇 |
1925年 | 1篇 |
1913年 | 1篇 |
排序方式: 共有182条查询结果,搜索用时 109 毫秒
81.
The consumption of bitter cassava by root boring, leaf chewing and leaf sucking insects was measured on a slash and burn agricultural site in the Amazon Territory of Venezuela. Chewing and boring insects consumed less than 3% of the tissue, possibly because of the presence of cyanogenic glucosides in the cassava plants. In contrast to the boring and chewing insects, leaf sucking insects were more effective herbivores. They may be able to consume the phloem sap without activating the hydrocyanic acid. However, even sucking insects consumed only about 14% of the phosphorus uptake of the plants. We conclude that insect herbivory did not play a major role in the decline of productivity on the slash and burn agricultural site. 相似文献
82.
83.
84.
Fendick EA Stevens GL Brown RJ Jordan WP 《Environmental pollution (Barking, Essex : 1987)》1989,58(2-3):155-178
Liver and kidney tissue samples from four rodent species collected in the Geysers geothermal steamfield of northern California were analyzed for content of 28 elements. Element concentrations in samples from the developed region of the Geysers were compared with samples from undeveloped reference regions to determine the influence of geothermal power development on element content in small mammal tissues. Eight elements (B, Ca, Cu, Mg, Mn, P, Sr, Ti) were enriched in samples from the Geysers, 12 (Ag, Al, Co, Cr, Fe, K, Mo, Na, Ni, Pb, Si, Zn) were decreased within the Geysers, Ba and Li were inconclusive, and six (As, Be, Cd, Hg, Sn, V) were below the minimum analytical limits. The longest-lived species (Neotoma fuscipes) had the greatest occurrence of statistically significant differences in element content. Sites in grassland habitat produced more significant differences in element content than either chaparral or streamside habitats for samples from Peromyscus maniculatus. Peromyscus boylii and P. truei provided additional data, but no distinct advantages for element monitoring. The data indicate regional influences from geothermal power development on element levels in rodent tissues. 相似文献
85.
86.
87.
88.
89.
90.