全文获取类型
收费全文 | 736篇 |
免费 | 57篇 |
出版年
2023年 | 3篇 |
2022年 | 5篇 |
2021年 | 7篇 |
2020年 | 5篇 |
2019年 | 4篇 |
2018年 | 11篇 |
2017年 | 7篇 |
2016年 | 11篇 |
2015年 | 14篇 |
2014年 | 28篇 |
2013年 | 43篇 |
2012年 | 47篇 |
2011年 | 45篇 |
2010年 | 35篇 |
2009年 | 21篇 |
2008年 | 47篇 |
2007年 | 34篇 |
2006年 | 42篇 |
2005年 | 59篇 |
2004年 | 55篇 |
2003年 | 48篇 |
2002年 | 27篇 |
2001年 | 18篇 |
2000年 | 13篇 |
1999年 | 22篇 |
1998年 | 11篇 |
1997年 | 6篇 |
1996年 | 5篇 |
1995年 | 4篇 |
1994年 | 5篇 |
1993年 | 4篇 |
1992年 | 10篇 |
1991年 | 8篇 |
1990年 | 7篇 |
1989年 | 8篇 |
1988年 | 10篇 |
1987年 | 6篇 |
1986年 | 9篇 |
1984年 | 4篇 |
1983年 | 6篇 |
1981年 | 6篇 |
1980年 | 3篇 |
1979年 | 4篇 |
1975年 | 2篇 |
1974年 | 3篇 |
1973年 | 3篇 |
1972年 | 4篇 |
1970年 | 2篇 |
1969年 | 2篇 |
1967年 | 3篇 |
排序方式: 共有793条查询结果,搜索用时 31 毫秒
791.
Bodyweight, breast girth and hind-foot length were compared in sika deer fawns (Cervus nippon Temminck) that were shot or had died naturally. The study site was Mount Goyo, in northern Japan. Samples were collected in January and February every year from 1982 to 1991 for the dead fawns and from 1990 to 1992 for the living fawns. The average bodyweight and the variation in bodyweight was significantly smaller in the dead fawns than in the living ones, suggesting a higher mortality rate in smaller fawns. The mean breast girth and hind-foot length were also significantly smaller in the dead fawns. Two possibilities are suggested: (i) the smaller fawns were born later than the larger fawns and grew at normal rates; or (ii) the smaller and larger fawns were born in a similar period but grew at different rates thereafter. 相似文献
792.
Akira Haraguchi 《Ecological Research》1992,7(3):205-212
A relationship was sought between species distribution and seasonal change in the redox property of peat in a floating mat
in Mizorogaike Pond, central Japan. The mat surface experienced an annual submergence-emergence cycle due to its sinking-rising
movement. Redox potential (Eh) of the surface peat showed little difference between communities in the mat in the submergence
season (January–June) and early emergence season (July–August). However variation in Eh among communities was clear in the
late emergence season (September–December). Among seven communities in the floating mat, theMenyanthes trifoliata-Rhynchospora fauriei, M. trifoliata-Eriocaulon sikokianum-E. bondoense f.pilosum, Sphagnum cuspidatum andM. trifoliata-Carex thunbergii communities had high Eh (400–600 mV) in the late emergence season, while theMenyanthes trifoliata andPhragmites australis-M. trifoliata communities had lower Eh (200–400 mV). TheM. trifoliata-Isachné globosa community was intermediate (300–500 mV). The earlier the emergence of the peat surface began, the higher the Eh became in
the late emergence season. 相似文献
793.