全文获取类型
收费全文 | 32727篇 |
免费 | 308篇 |
国内免费 | 252篇 |
专业分类
安全科学 | 756篇 |
废物处理 | 1360篇 |
环保管理 | 3741篇 |
综合类 | 6318篇 |
基础理论 | 8183篇 |
环境理论 | 15篇 |
污染及防治 | 8546篇 |
评价与监测 | 2212篇 |
社会与环境 | 2007篇 |
灾害及防治 | 149篇 |
出版年
2022年 | 320篇 |
2021年 | 326篇 |
2020年 | 205篇 |
2019年 | 265篇 |
2018年 | 519篇 |
2017年 | 568篇 |
2016年 | 800篇 |
2015年 | 618篇 |
2014年 | 924篇 |
2013年 | 2443篇 |
2012年 | 1062篇 |
2011年 | 1441篇 |
2010年 | 1155篇 |
2009年 | 1172篇 |
2008年 | 1422篇 |
2007年 | 1466篇 |
2006年 | 1278篇 |
2005年 | 1068篇 |
2004年 | 1072篇 |
2003年 | 1036篇 |
2002年 | 964篇 |
2001年 | 1171篇 |
2000年 | 794篇 |
1999年 | 531篇 |
1998年 | 339篇 |
1997年 | 387篇 |
1996年 | 395篇 |
1995年 | 435篇 |
1994年 | 435篇 |
1993年 | 370篇 |
1992年 | 379篇 |
1991年 | 370篇 |
1990年 | 369篇 |
1989年 | 345篇 |
1988年 | 306篇 |
1987年 | 293篇 |
1986年 | 288篇 |
1985年 | 289篇 |
1984年 | 301篇 |
1983年 | 297篇 |
1982年 | 292篇 |
1981年 | 253篇 |
1980年 | 239篇 |
1979年 | 237篇 |
1978年 | 214篇 |
1977年 | 215篇 |
1975年 | 181篇 |
1974年 | 195篇 |
1973年 | 177篇 |
1972年 | 168篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
111.
As a consequence of decreases in the emission rate of sulphur in eastern North America in the late 1970s and early 1980s, sulphate deposition in central Ontario declined by about 40%, but has remained constant for about six years. Plastic Lake, a small, dilute lake on the Precambrian shield that the authors have studied since 1979, acidified between the start of the study and about 1986, but since then has not changed. The authors also monitored the chemistry of streamwater draining the Plastic Lake catchment. Water quality of runoff from an upland site improved rapidly (pH and alkalinity increased, SO4(2-) and Al decreased), but two factors offset these improvements. A small wetland area downstream reversed most of these changes, resulting in a constant output of strong acid from the catchment. In addition, in extremely dry years (1983, 1987, 1989) there were very high concentrations of SO4(2-) in the streamwater, suggesting substantial re-oxidation of reduced S in the catchment. 相似文献
112.
Khan Syed Abdul Rehman Mathew Manoj Dominic P. D. D. Umar Muhammad 《Environment, Development and Sustainability》2022,24(9):10633-10665
Environment, Development and Sustainability - Environmental deterioration and global warming has created a substantial impact on international companies to incorporate eco-friendly, green supply... 相似文献
113.
Biaou Séverin Gouwakinnou Gerard Nounagnon Biaou Honoré Samadori Sorotori Tovihessi Marc Sèwanou Awessou Beranger Kohomlan Ahononga Fiacre Codjo Houéto Felix Ogoubiyi 《Environment, Development and Sustainability》2022,24(8):9885-9905
Environment, Development and Sustainability - Land use and land cover change (LULCC) is one of the problems that the world has been facing for the last few decades despite political attention.... 相似文献
114.
Environment, Development and Sustainability - This study describes the results of groundwater table variation in Thanjavur District before and after the monsoon seasons. Groundwater-level data... 相似文献
115.
Russian Journal of Ecology - Abstract—We tested a hypothesis about the different abilities of alien and native plants to form arbuscular mycorrhizae. The studies were carried out in the... 相似文献
116.
Rate-temperature responses in scyphozoan medusae and polyps 总被引:1,自引:0,他引:1
The effects of temperature on oxygen consumption and spontaneous rhythmic activity have been investigated in various stages of the life histories of 3 species of jellyfish from the Chesapeake Bay, USA. All 3 species clearly show the ability to acclimate positively to temperature change. Thermal sensitivity of metabolism in the winter medusa Cyanea capillata fulva is fairly low at temperature intervals which are experienced in nature. Polyps of the two summer medusae, Chrysaora quinquecirrha and Aurelia aurita, show reduced metabolic sensitivity at temperatures normally accompanying high developmental activity and the onset of strobilation. 相似文献
117.
118.
119.
120.