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   105248篇
  免费   2194篇
  国内免费   6584篇
安全科学   4937篇
废物处理   4221篇
环保管理   15198篇
综合类   30509篇
基础理论   28531篇
环境理论   74篇
污染及防治   19034篇
评价与监测   6063篇
社会与环境   4225篇
灾害及防治   1234篇
  2023年   657篇
  2022年   1496篇
  2021年   1516篇
  2020年   1254篇
  2019年   1332篇
  2018年   1694篇
  2017年   1852篇
  2016年   2804篇
  2015年   2682篇
  2014年   3845篇
  2013年   10819篇
  2012年   3566篇
  2011年   3911篇
  2010年   4427篇
  2009年   4553篇
  2008年   3246篇
  2007年   2893篇
  2006年   3250篇
  2005年   2856篇
  2004年   3008篇
  2003年   2864篇
  2002年   2379篇
  2001年   2507篇
  2000年   2397篇
  1999年   1866篇
  1998年   1656篇
  1997年   1680篇
  1996年   1713篇
  1995年   1790篇
  1994年   1628篇
  1993年   1449篇
  1992年   1427篇
  1991年   1342篇
  1990年   1300篇
  1989年   1214篇
  1988年   1065篇
  1987年   991篇
  1986年   999篇
  1985年   1075篇
  1984年   1168篇
  1983年   1168篇
  1982年   1185篇
  1981年   1102篇
  1980年   942篇
  1979年   925篇
  1978年   817篇
  1977年   716篇
  1976年   638篇
  1973年   632篇
  1972年   636篇
排序方式: 共有10000条查询结果,搜索用时 533 毫秒
51.
随着遥感数据源的不断丰富,遥感技术不断提高,可以解决越来越多的水环境问题。指出了当前水生态环境管理方面的主要需求,结合目前遥感技术的发展,对国内外的水环境遥感研究进展进行综述。以湖泊富营养化监测与评估、核电站温排水遥感监测及城市黑臭水体遥感监测为案例,具体阐述遥感在水环境管理中的应用方法及成效。未来水生态环境管理发展趋势将以水污染防治为主向水污染防治和水生态修复与保护并重发展。基于此趋势,提出遥感在水生态修复的应用潜力,利于更多地方部门积极有效应用遥感技术,解决水生态环境问题。  相似文献   
52.
Climate change poses water resource challenges for many already water stressed watersheds throughout the world. One such watershed is the Upper Neuse Watershed in North Carolina, which serves as a water source for the large and growing Research Triangle Park region. The aim of this study was to quantify possible changes in the watershed’s water balance due to climate change. To do this, we used the Soil and Water Assessment Tool (SWAT) model forced with different climate scenarios for baseline, mid‐century, and end‐century time periods using five different downscaled General Circulation Models. Before running these scenarios, the SWAT model was calibrated and validated using daily streamflow records within the watershed. The study results suggest that, even under a mitigation scenario, precipitation will increase by 7.7% from the baseline to mid‐century time period and by 9.8% between the baseline and end‐century time period. Over the same periods, evapotranspiration (ET) would decrease by 5.5 and 7.6%, water yield would increase by 25.1% and 33.2%, and soil water would increase by 1.4% and 1.9%. Perhaps most importantly, the model results show, under a high emission scenario, large seasonal differences with ET estimated to decrease by up to 42% and water yield to increase by up to 157% in late summer and fall. Planning for the wetter predicted future and corresponding seasonal changes will be critical for mitigating the impacts of climate change on water resources.  相似文献   
53.
54.
55.
56.
Environmental Science and Pollution Research - China is the most populous country in the world, and the pollution caused by the excessive population should not be underestimated. In recent years,...  相似文献   
57.
58.
Research suggests that encouraging motivated residents to reach out to others in their social network is an effective strategy for increasing the scale and speed of conservation action adoption. However, little is known about how to effectively encourage large numbers of residents to reach out to others about conservation causes. We examined the influence of normative and efficacy-based messaging at motivating residents to engage in and to encourage others to participate in native plant gardening in their community. To do so, we conducted a field experiment with messages on mailings and tracked native plant vouchers used. Efficacy messages tended to be more effective than normative messages at increasing residents’ willingness to reach out to others to encourage conservation action, as indicated by a several percentage point increase in native plant voucher use by residents’ friends and neighbors. Messages sometimes had different impacts on residents based on past behaviors and perceptions related to native plant gardening. Among these subgroups, efficacy and combined efficacy and norm messages most effectively encouraged individual and collective actions, as indicated by increased voucher usage. Our findings suggest that interventions that build residents’ efficacy for engaging in a conservation behavior and for reaching out to others may be a promising path forward for outreach. However, given our results were significant at a false discovery rate cutoff of 0.25 but not 0.05, more experimental trials are needed to determine the robustness of these trends.  相似文献   
59.
Environmental Science and Pollution Research - Pesticides might increase the production of reactive oxygen species (ROS). Dicamba (DIC) and 2,4-dichlorophenoxyacetic acid (2,4-D) are auxinic...  相似文献   
60.
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