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   1034篇
  免费   80篇
  国内免费   96篇
安全科学   115篇
废物处理   8篇
环保管理   207篇
综合类   457篇
基础理论   175篇
环境理论   2篇
污染及防治   23篇
评价与监测   30篇
社会与环境   134篇
灾害及防治   59篇
  2023年   12篇
  2022年   22篇
  2021年   31篇
  2020年   27篇
  2019年   26篇
  2018年   21篇
  2017年   49篇
  2016年   38篇
  2015年   35篇
  2014年   37篇
  2013年   82篇
  2012年   59篇
  2011年   68篇
  2010年   56篇
  2009年   59篇
  2008年   42篇
  2007年   85篇
  2006年   60篇
  2005年   59篇
  2004年   48篇
  2003年   45篇
  2002年   37篇
  2001年   35篇
  2000年   36篇
  1999年   19篇
  1998年   17篇
  1997年   14篇
  1996年   13篇
  1995年   15篇
  1994年   8篇
  1993年   9篇
  1992年   7篇
  1991年   5篇
  1990年   1篇
  1989年   5篇
  1988年   4篇
  1987年   1篇
  1986年   1篇
  1985年   3篇
  1984年   1篇
  1982年   3篇
  1981年   2篇
  1980年   3篇
  1979年   2篇
  1978年   1篇
  1977年   2篇
  1973年   1篇
  1972年   1篇
  1971年   1篇
  1970年   1篇
排序方式: 共有1210条查询结果,搜索用时 31 毫秒
91.
ABSTRACT: The potential for hydroelectric power development at existing dams is great in oil dependent New England where there are over 10,000 dams presently in existence. Over 400 developments have been proposed in the region, the majority of which are small scale, and do not have major environmental impacts. Nevertheless, a variety of constraints may hinder development. A study of three efforts by municipalities in unique positions to develop hydropower reveals that organizational and political considerations are significant factors affecting development. Successful hydropower development requires: (1) the cooperation and interaction of citizens, government, and the private sector; (2) community interest and education; and (3) strong resolve.  相似文献   
92.
Climate governance in Small Island developing States (SIDS) is a pressing priority to preserve livelihoods, biodiversity and ecosystems for the next generations. Understanding the dynamics of climate change policy integration is becoming more crucial as we try to measure the success of environmental governance efforts and chart new goals for sustainable development. At the international level, climate change policy has evolved from single issue to integrated approaches towards achieving sustainable development. New actors, new mechanisms and institutions of governance with greater fragmentation in governance across sectors and levels (Biermann and Pattberg, 2008) make integration of policy in the area of climate change governance even more of a challenge today. What is the Caribbean reality regarding policy coherence in climate change governance? Are the same climate change policy coherence frameworks useful or indeed applicable for environmental governance in developing states more generally and for SIDS in particular? What are the best triggers to achieve successful climate change policy integration in environmental governance—especially as the complex interconnectivity of new actors, institutions and mechanisms make the process of integration even more challenging? What facilitates and what hampers climate policy integration in the regional Caribbean context? This article reviews the debates around policy coherence for climate change governance, creates a framework to test or measure policy coherence and examines how relevant this has been to regional climate change governance processes in Commonwealth Caribbean States. The study found that though at the regional level, there is substantial recognition of the importance of and mechanics involved in climate policy coherence, this has not translated to policy coherence at the regional and national levels. There is a large degree of fragmentation in the application of climate policy in each Caribbean Island with no mechanism to breach the gap. Silos in public environmental governance architectures, unwillingness to share data, insufficient political will; unsustainable project-based funding and lack of accountability among actors are the main challenges to climate policy coherence. The findings fill a gap in the literature on the elements of climate policy coherence from a SIDS perspective.  相似文献   
93.
94.
发达与欠发达地区耕地保护行为中的利益机制分析   总被引:6,自引:0,他引:6  
本文从当前发达与欠发达地区耕地保护上的利益矛盾入手,以它们之间的内在经济关系为基础,运用局部均衡分析方法,构建了一个简单的经济模型,对上述矛盾“零和博弈”的长期效应进行了揭示,并讨论了消除这种不良影响的政策或制度安排。  相似文献   
95.
96.
97.
基准地价评估及更新是目前土地管理的一项重要和经常性的工作。针对小城镇的土地利用特点,对小城镇土地定级估价更新中的地价样本祷点、土地级别调整、基准地价更新评估等方面进行了研究,选择级别界线修订法更新小城镇土地级别,并在此基础上探索出适合小城镇特点的基准地价更新方法。  相似文献   
98.
99.
Over the past few years, the eco-industrial park (EIP) concept has been emerging as a significant driving force for sustainable industrialisation. Accumulating evidence indicates that the transition of existing industries into eco-industrial networking through industrial ecology (IE) principles would provide an excellent opportunity for facilitating such innovative industrialisation. A SWOT analysis was carried out to identify the potential and constraints for the successful implementation of an eco-industrial park in the ecologically fragile coastal zone of Puducherry. The results indicated significant potential for EIP development with few challenges. The lessons learnt can be used to provide broad guidelines for facilitating EIP development in the Puducherry region and similar scenarios found elsewhere across the world, especially in developing countries.  相似文献   
100.
亚热带丘陵小流域土壤有效磷空间变异与淋失风险研究   总被引:7,自引:1,他引:6  
肥料过施导致的土壤磷素累积和淋失是农业面源污染的重要方面.以湖南省长沙县金井镇脱甲河小流域(52 km2)为研究区,采用高密度布点采样、Arc GIS软件和属性相似反距离加权插值法研究了亚热带丘陵小流域表层(0~20 cm)土壤有效磷(Olsen-P)含量(以P计,下同)的空间分布特征与磷素的淋失风险.结果表明,菜地、果园、稻田和茶园土壤Olsen-P平均含量为62.0、16.1、14.4和13.7 mg·kg-1,是林地(平均含量为2.36 mg·kg-1)的5.8~26.3倍.5个土地利用类型土壤Olsen-P含量均具有高等变异水平和中等程度的空间自相关性(块基比C0/(C0+C)=50%),这与区内地形地貌、土壤母质、人工施肥等具有密切关系.根据土壤0.01 mol·L-1Ca Cl2浸提态P和Olsen-P的非线性关系可确定区内红壤和水稻土P的淋失风险临界值分别为69.97和98.40 mg·kg-1,并据此对脱甲河小流域土壤磷素淋失的风险进行了定量评价,结果表明旱地土壤具有明显较高的淋失风险,其中中等以上的比例占36.4%,而稻田土壤仅有0.2%,为中等以上淋失风险.因此,控制旱地(尤其是菜地)磷肥的投入是降低亚热带丘陵小流域土壤P淋失风险和减轻农业面源污染的关键.  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