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   108篇
  免费   3篇
安全科学   14篇
废物处理   1篇
环保管理   27篇
综合类   36篇
基础理论   10篇
污染及防治   7篇
评价与监测   6篇
社会与环境   5篇
灾害及防治   5篇
  2020年   2篇
  2017年   1篇
  2016年   5篇
  2015年   1篇
  2014年   3篇
  2013年   6篇
  2012年   4篇
  2011年   5篇
  2010年   2篇
  2009年   8篇
  2008年   5篇
  2007年   3篇
  2006年   3篇
  2005年   2篇
  2004年   6篇
  2003年   2篇
  2002年   4篇
  2001年   5篇
  2000年   2篇
  1999年   6篇
  1998年   7篇
  1997年   6篇
  1996年   4篇
  1995年   8篇
  1994年   7篇
  1993年   2篇
  1987年   1篇
  1985年   1篇
排序方式: 共有111条查询结果,搜索用时 15 毫秒
81.
This article aims to highlight the current status of compliance to Machinery Directive 98/37/EC (transposed to Spanish regulation as RD 56/1995, of 20th January) (a new directive numbered as 2006/42/EC [Directive 2006/42/EC of the European Parliament and of the Council of 17 may 2006 on machinery, and amending Directive 95/16/EC (recast). OJ L157/24-86, 9.6.2006.], that recasts and replaced 98/37/ED directive and its amendments, came into force on 29 June 2006; it will not be applied until 29th December 2009. European Member States have a lead-time of two years to adopt and publish the national laws and regulations transposing the provisions of the new Directive into national law. Latest 10th October, Spain transposed Machinery Directive 2006/42/EC to national regulation as Real Decreto 1644/2008 [Real Decreto 1644/2008, de 10 de octubre, por el que se establecen las normas para la comercialización y puesta en servicio de las máquinas. BOE 246/2008, de 11 octubre 2008. Páginas 40995–41030]) of a particular family of machinery (hand-held, medium and small-size, deeply introduced in the market, of low-medium cost), that any user, professional or non-professional, can acquire as first-hand in any of the sales points (whether or not experts in these kind of products).At the same time, it emphasises the most significant shortcomings and non-conformities found, after analyzing the results of five consecutive Campaigns of Control of Industrial Products performed by one of the labs (placed in Spain) involved in the market surveillance European Program.  相似文献   
82.
The Expansion of Farm-Based Plantation Forestry in Vietnam   总被引:2,自引:0,他引:2  
This study targets plantation forestry by farm households (small holders), which is increasing globally and most rapidly in China and Vietnam. By use of an interdisciplinary approach on three study sites in Vietnam, we examined the trends in farmers’ tree planting over time, the various pre-requisites for farm-based plantation forestry and its impact on rural people’s livelihood strategies, socio-economic status, income and security. The findings indicated a change from subsistence to cash-based household economy, diversification of farmers’ incomes and a transformation of the landscape from mainly natural forests, via deforestation and shifting cultivation, to a landscape dominated by farm-based plantations. The trend of transformation, over a period of some 30 years, towards cash crops and forestry was induced by a combination of policy, market, institutional, infrastructural and other conditions and the existence of professional farming communities, and was most rapid close to the industrial market.  相似文献   
83.
Research on the benefits of local ecological knowledge for conservation lacks empirical data on the pathways through which local knowledge might affect natural resources management. We test whether ethnobotanical skills, a proxy for local ecological knowledge, are associated to the clearance of forest through their interaction with agricultural labor. We collected information from men in a society of gatherers–horticulturalist, the Tsimane’ (Bolivia). Data included a baseline survey, a survey of ethnobotanical skills (n = 190 men), and two surveys on agricultural labor inputs (n = 466 plots). We find a direct effect of ethnobotanical skills in lowering the extent of forest cleared in fallow but not in old-growth forest. We also find that the interaction between ethnobotanical skills and labor invested in shifting cultivation has opposite effects depending on whether the clearing is done in old-growth or fallow forest. We explain the finding in the context of Tsimane’ increasing integration to the market economy.  相似文献   
84.
As in other mountain regions of Asia, agricultural lands in the Chittagong Hill Tracts (CHT) of Bangladesh are undergoing degradation due primarily to environmentally incompatible land-use systems such as shifting cultivation (jhum) and annual cash crops. The suitable land-use systems such as agroforestry and timber tree plantation provide benefit to the society at large, but they might not provide attractive economic benefits to farmers, eventually constraining a wide-scale adoption of such land-use systems. Therefore, it is essential to evaluate agricultural land-use systems from both societal and private perspectives in the pursuit of promoting particularly environmentally sustainable systems. This article evaluated five major land-use systems being practiced in CHT, namely jhum, annual cash crops, horticulture, agroforestry, and timber plantation. The results of the financial analysis revealed the annual cash crops as the most attractive land use and jhum as the least attractive of the five land-use systems considered under the study. Horticulture, timber plantation, and agroforestry, considered to be suitable land-use systems particularly for mountainous areas, held the middle ground between these two systems. Annual cash crops provided the highest financial return at the cost of a very high rate of soil erosion. When the societal cost of soil erosion is considered, annual cash crops appear to be the most costly land-use system, followed by jhum and horticulture. Although financially less attractive compared to annual cash crops and horticulture, agroforestry and timber plantation are the socially most beneficial land-use systems. Findings of the alternative policy analyses indicate that there is a good prospect for making environmentally sustainable land-use systems, such as agroforestry and timber plantation, attractive for the farmers by eliminating existing legal and institutional barriers, combined with the provision of necessary support services and facilities.
Golam RasulEmail:
  相似文献   
85.
Current “business as usual” projections suggest greenhouse gas emissions from industrialized nations will grow substantially over the next decade. However, if it comes into force, the Kyoto Protocol will require industrialized nations to reduce emissions to an average of 5% below 1990 levels in the 2008–2012 period. Taking early action to close this gap has a number of advantages. It reduces the risks of passing thresholds that trigger climate change “surprises.” Early action also increases future generations' ability to choose greater levels of climate protection, and it leads to faster reductions of other pollutants. From an economic sense, early action is important because it allows shifts to less carbon-intensive technologies during the course of normal capital stock turnover. Moreover, many options for emission reduction have negative costs, and thus are economically worthwhile, because of paybacks in energy costs, healthcare costs, and other benefits. Finally, early emission reductions enhance the probability of successful ratification and lower the risk of noncompliance with the protocol. We discuss policy approaches for the period prior to 2008. Disadvantages of the current proposals for Credit for Early Action are the possibility of adverse selection due to problematic baseline calculation methods as well as the distributionary impacts of allocating a part of the emissions budget already before 2008. One simple policy without drawbacks is the so-called baseline protection, which removes the disincentive to early action due to the expectation that businesses may, in the future, receive emission rights in proportion to past emissions. It is particularly important to adopt policies that shift investment in long-lived capital stock towards less carbon-intensive technologies and to encourage innovation and technology development that will reduce future compliance costs.  相似文献   
86.
本文分别从市场准入、价格、服务质量以及风险等方面,对城市环境基础设施市场化运营中的政府规制进行了具体分析。  相似文献   
87.
本文首先对我国环保投入的现状及存在的问题进行了分析,然后提出了确定环保投入的三项原则,在此基础上,对我国未来的环保投入运行机制进行了较为深入的分析。  相似文献   
88.
从跨世纪前夕的角度,论述了我国环境科技的主要任务及其改革重点,展望了环境科技机构在市场经济中新的发展模式,并分析了为推动环境科技发展的主要资金渠道的可能性。  相似文献   
89.
乡镇企业发展中的环境问题及法律对策   总被引:2,自引:0,他引:2  
杨国胜 《上海环境科学》1997,16(8):11-12,25
文章提出了乡镇企业在迅速发展的同时,带来的严重的环境问题,从企业的外部不经济性、布局和产业结构的不合理性、生产手段的落后、立法的不完善及执法的不力等几个方面论述了产生问题的背景原因,探讨了相应的法律对策,要求加强建立我国乡镇企业环境管理地方性立法工作,并在立法中明确排污费的使用,企业产权关系,排污交易制度及环境损害责任保险制度等内容。  相似文献   
90.
对沈阳市秋白菜上市引发的环境污染作了调查、测试、并对净菜上市的环境效益进行了分析研究。  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