首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   90277篇
  免费   1239篇
  国内免费   1109篇
安全科学   3579篇
废物处理   3276篇
环保管理   14068篇
综合类   21214篇
基础理论   26367篇
环境理论   74篇
污染及防治   14404篇
评价与监测   5466篇
社会与环境   3626篇
灾害及防治   551篇
  2022年   745篇
  2021年   812篇
  2020年   655篇
  2019年   865篇
  2018年   1040篇
  2017年   1184篇
  2016年   2179篇
  2015年   1839篇
  2014年   2603篇
  2013年   9316篇
  2012年   2221篇
  2011年   2486篇
  2010年   3304篇
  2009年   3425篇
  2008年   1990篇
  2007年   1816篇
  2006年   2300篇
  2005年   2256篇
  2004年   2562篇
  2003年   2427篇
  2002年   1954篇
  2001年   2225篇
  2000年   1869篇
  1999年   1489篇
  1998年   1344篇
  1997年   1332篇
  1996年   1447篇
  1995年   1573篇
  1994年   1483篇
  1993年   1316篇
  1992年   1322篇
  1991年   1287篇
  1990年   1240篇
  1989年   1202篇
  1988年   1053篇
  1987年   972篇
  1986年   1000篇
  1985年   1071篇
  1984年   1163篇
  1983年   1175篇
  1982年   1178篇
  1981年   1098篇
  1980年   950篇
  1979年   919篇
  1978年   819篇
  1977年   708篇
  1976年   638篇
  1975年   601篇
  1973年   627篇
  1972年   622篇
排序方式: 共有10000条查询结果,搜索用时 316 毫秒
1.
2.
Russian Journal of Ecology - In this paper, Ellenberg’s indicator values were estimated in order to soil nitrogen (N), pH (R) and soil moisture (M) in different subalpine grassland...  相似文献   
3.
Environmental Science and Pollution Research - This study aims to re-examine the impacts of monetary and fiscal policy on environmental quality in ASEAN countries from 1990 to 2019. We utilized the...  相似文献   
4.
Russian Journal of Ecology - A new method for assessing the response of biota to climatic changes in the ecosystem has been tested. In the Central Forest Natural Biosphere Reserve, the average...  相似文献   
5.
Environment, Development and Sustainability - Sugarcane is an industrial crop globally used for producing biofuels and bioproducts and is the only source of white sugar in Bangladesh. However,...  相似文献   
6.
Environmental Science and Pollution Research - Organic contaminants are known to affect a suite of physiological processes across vertebrate clades. However, despite their ancient lineage and...  相似文献   
7.
•Bacterially-mediated coupled N and Fe processes examined in incubation experiments. •NO3 reduction was considerably inhibited as initial Fe/N ratio increased. •The maximum production of N2 occurred at an initial Fe/N molar ratio of 6. •Fe minerals produced at Fe/N ratios of 1–2 were mainly easily reducible oxides. The Fe/N ratio is an important control on nitrate-reducing Fe(II) oxidation processes that occur both in the aquatic environment and in wastewater treatment systems. The response of nitrate reduction, Fe oxidation, and mineral production to different initial Fe/N molar ratios in the presence of Paracoccus denitrificans was investigated in 132 h incubation experiments. A decrease in the nitrate reduction rate at 12 h occurred as the Fe/N ratio increased. Accumulated nitrite concentration at Fe/N ratios of 2–10 peaked at 12–84 h, and then decreased continuously to less than 0.1 mmol/L at the end of incubation. N2O emission was promoted by high Fe/N ratios. Maximum production of N2 occurred at a Fe/N ratio of 6, in parallel with the highest mole proportion of N2 resulting from the reduction of nitrate (81.2%). XRD analysis and sequential extraction demonstrated that the main Fe minerals obtained from Fe(II) oxidation were easily reducible oxides such as ferrihydrite (at Fe/N ratios of 1–2), and easily reducible oxides and reducible oxides (at Fe/N ratios of 3–10). The results suggest that Fe/N ratio potentially plays a critical role in regulating N2, N2O emissions and Fe mineral formation in nitrate-reducing Fe(II) oxidation processes.  相似文献   
8.
Environment, Development and Sustainability - Globally, traditional knowledge is at stake, notwithstanding intentions recorded in international policy conventions. Egypt has accepted and ratified...  相似文献   
9.
Russian Journal of Ecology - Climate change entails shifts in the ranges of woody plants along both latitudinal and altitudinal gradients in the boreal forest biome. In this study,...  相似文献   
10.
Environmental Science and Pollution Research - Lake Mariut Main Basin (MB) is not only one of the three basins composing Lake Mariut (LM) but is also the main source of the popular tilapia fish to...  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号