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   1728篇
  免费   118篇
  国内免费   503篇
安全科学   167篇
废物处理   67篇
环保管理   129篇
综合类   993篇
基础理论   273篇
污染及防治   335篇
评价与监测   143篇
社会与环境   154篇
灾害及防治   88篇
  2024年   8篇
  2023年   35篇
  2022年   106篇
  2021年   79篇
  2020年   83篇
  2019年   59篇
  2018年   84篇
  2017年   90篇
  2016年   80篇
  2015年   93篇
  2014年   102篇
  2013年   157篇
  2012年   112篇
  2011年   116篇
  2010年   88篇
  2009年   137篇
  2008年   111篇
  2007年   95篇
  2006年   113篇
  2005年   59篇
  2004年   73篇
  2003年   75篇
  2002年   88篇
  2001年   66篇
  2000年   72篇
  1999年   41篇
  1998年   28篇
  1997年   19篇
  1996年   21篇
  1995年   12篇
  1994年   15篇
  1993年   6篇
  1992年   6篇
  1991年   10篇
  1990年   4篇
  1988年   2篇
  1986年   1篇
  1984年   3篇
排序方式: 共有2349条查询结果,搜索用时 218 毫秒
61.
传统的基坑支护结构设计具有相当的模糊性和不确定性 ,可能危及基坑和周围环境的安全。笔者利用深基坑支护体系的监测数据 ,采用灰色系统理论建立了基坑工程变形的GM(1 ,1 )预测模型 ,其模型的两个参数可识别基坑变形发展势态 ,并由此讨论了模型的适用范围。最后 ,运用该模型预测分析实际基坑工程支护结构变形 ,表明其预测模型可用于基坑动态设计与信息化施工  相似文献   
62.
我国公共场所禁烟现状及对策分析   总被引:1,自引:0,他引:1  
张菊英  吴涛  马骁  文雯 《四川环境》2004,23(3):90-92
分析目前我国公共场所禁烟现状,探讨进一步加强公共场所禁烟工作的对策。方法:对四川、贵州、浙江、广西等地区的疾病控制中心、卫生监督所以及健康教育所的工作人员进行定性访谈,并结合文献综述。结果:尽管我国公共场所的禁烟工作取得了一些成绩,但仍存在很多不足之处。结论:公共场所彻底禁烟不仅需要烟民的自觉禁烟,也需要政府有关法令的力行实施,更需要全社会广大群众的共同参与。  相似文献   
63.
针对影响水源热泵系统运行效能的地下水水质和回灌过程中井堵塞的问题,提出相应的水质处理方法和水源热泵用地下水水质参考标准.  相似文献   
64.
Water eutrophication in subtropical regions of southern China threatens watershed health and is of major concern. However, annual phosphorus (P) loading and its dominant causes are still unclear, especially at the watershed scale. In this study, we investigated dynamic P loadings and associated factors (e.g., land use, livestock production, and runoff depth) in ten watersheds that varied in area from 9 to 5,212 ha in a hilly area of Hunan Province, China. A flowmeter was installed at the outlet of each watershed, and total P (TP) and soluble P (SP) concentrations were monitored periodically from June 2010 to October 2012. The results showed that annual P loadings (APLs) in the ten watersheds ranged from 22.8 to 247.8 kg P/km2 and that P loss primarily occurred from April to June of each year during the main rainfall season in the study area. In addition, the average eutrophication (>0.05 mg P/L) ratio for stream waters was 86.7 % during the study period, which was indicative of a potentially serious condition for the local water environments. Annual P loadings were linearly related to livestock density (LD; R?=?0.92, p?<?0.01), whereas the eutrophication ratio of stream water was significantly (p?<?0.05) correlated with LD (R?=?0.61), percentage cropland (R?=?0.71), and percentage forest cover (R?=??0.68). Thus, it is concluded that the control of livestock production has the greatest potential for reducing P loadings in watersheds in this subtropical area. This will be beneficial to the amelioration and protection of local environment.  相似文献   
65.
Conservation and development practitioners increasingly promote community forestry as a way to conserve ecosystem services, consolidate resource rights, and reduce poverty. However, outcomes of community forestry have been mixed; many initiatives failed to achieve intended objectives. There is a rich literature on institutional arrangements of community forestry, but there has been little effort to examine the role of socioeconomic, market, and biophysical factors in shaping both land‐cover change dynamics and individual and collective livelihood outcomes. We systematically reviewed the peer‐reviewed literature on community forestry to examine and quantify existing knowledge gaps in the community‐forestry literature relative to these factors. In examining 697 cases of community forest management (CFM), extracted from 267 peer‐reviewed publications, we found 3 key trends that limit understanding of community forestry. First, we found substantial data gaps linking population dynamics, market forces, and biophysical characteristics to both environmental and livelihood outcomes. Second, most studies focused on environmental outcomes, and the majority of studies that assessed socioeconomic outcomes relied on qualitative data, making comparisons across cases difficult. Finally, there was a heavy bias toward studies on South Asian forests, indicating that the literature on community forestry may not be representative of decentralization policies and CFM globally.  相似文献   
66.
Environmental Science and Pollution Research - It is of great significance for the coordinated development of the environment and the economy to study the impact of the human driving factors of...  相似文献   
67.
Environmental Science and Pollution Research - The livestock manure nitrogen load on farmland (LMNLF) is often used to assess the potential environmental pollution risk of livestock manure nitrogen...  相似文献   
68.
Environmental Science and Pollution Research - Paspalum distichum L. was tested to evaluate their phytoremediation capacity for Hg contaminated soil through analyzing the dissipation of Hg in soil...  相似文献   
69.
Environmental Science and Pollution Research - Soil erosion threatens environmental sustainability worldwide. Exploring the trajectories of soil erosion and associated drivers is of great...  相似文献   
70.
Environmental Science and Pollution Research - In the process of coal gangue surface accumulation and underground filling disposal, the heavy metals contained in coal gangue will inevitably...  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