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   804篇
  免费   14篇
  国内免费   13篇
安全科学   68篇
废物处理   3篇
环保管理   230篇
综合类   213篇
基础理论   150篇
污染及防治   79篇
评价与监测   32篇
社会与环境   39篇
灾害及防治   17篇
  2024年   1篇
  2023年   4篇
  2022年   9篇
  2021年   14篇
  2020年   16篇
  2019年   9篇
  2018年   5篇
  2017年   21篇
  2016年   22篇
  2015年   9篇
  2014年   21篇
  2013年   33篇
  2012年   17篇
  2011年   67篇
  2010年   32篇
  2009年   81篇
  2008年   67篇
  2007年   49篇
  2006年   39篇
  2005年   31篇
  2004年   37篇
  2003年   26篇
  2002年   27篇
  2001年   15篇
  2000年   19篇
  1999年   24篇
  1998年   20篇
  1997年   13篇
  1996年   24篇
  1995年   6篇
  1994年   11篇
  1993年   14篇
  1992年   8篇
  1991年   6篇
  1990年   2篇
  1989年   2篇
  1988年   1篇
  1987年   3篇
  1986年   2篇
  1985年   7篇
  1984年   2篇
  1983年   2篇
  1982年   2篇
  1980年   6篇
  1979年   2篇
  1978年   2篇
  1968年   1篇
排序方式: 共有831条查询结果,搜索用时 31 毫秒
811.
面对国际社会知识与经济的迅猛发展,特别是伴随我国自主创新、努力掌握环境保护核心与关键技术以及知识产权保护战略决策的实施,国际环境技术转移的知识产权保护法律调整问题也不断扩大其内涵。针对我国运用知识产权参与国际竞争的能力与经验的欠缺,本文从多方位关注和介绍国际环境技术转移中知识产权保护的有关法律规制,以对我国重构国际环境技术转移知识产权保护体系有所裨益。  相似文献   
812.
硝酸盐污染饮用水的去除技术研究进展   总被引:2,自引:0,他引:2  
近年来,世界上许多地区的饮用水硝酸盐污染日益严重,因为饮用水中的硝酸盐易导致"蓝婴综合症"而使其倍受关注。本文阐述了地下水硝酸盐氮的化学、物理及生物去除技术的最新研究进展,探讨了其今后的研究方向。  相似文献   
813.
重金属污染水体的高效环保处理技术及研究进展   总被引:2,自引:0,他引:2  
重金属污染作为影响环境的严重问题之一,不仅因其毒性大、易积累,而且处理后难以回收,对于重金属污染水体的处理技术,大部分仍存在成本高,易造成二次污染等问题。本文综述目前在处理工业废水中重金属离子的多种工艺技术,从环境保护、经济效益角度分析碳黑泥、矿物材料、树脂等的优缺点,提出发展高效环保型的处理技术,包括天然处理剂的应用,如竹炭,壳聚糖,微生物等,为去除重金属、净化水质提供新思路。  相似文献   
814.
介绍了在RS的支持下,以Landsat TM和CBERS卫星影像为主要的数据来源,采用栅格数据、遥感数据与统计数据相结合的技术路线,通过目视解译、人机交互解译、计算机自动识别等遥感信息提取技术和遥感影像处理方法,得出近20a三北防护林地区林地面积的变化情况。结果表明:三北防护林地区的林地面积1986—1995年有所减小,1995年以后呈逐年增加的趋势。  相似文献   
815.
Institutions play an important role in the adaptive capacity of a system in responding to climate change. This review paper characterizes the status of the collective institutional response (government, industry, First Nation, community, civil society) to climate change in the forest sector of the Canadian province of Ontario, and highlights the presence and nature of inter-institutional networks as part of the response. Based on a synthesis of the commonalities in the public administration and policy literature on tackling wicked problems, and the resilience literature, inter-institutional networks, which foster exchange of different types of knowledge, are an important aspect of enhancing the adaptive capacity of social–ecological systems such as the forest sector. Based on a content analysis of publicly available documents and insights gained from representatives of government, community members and non-governmental organizations, mitigation and adaptations strategies are described. At the provincial level there have been some new innovations in inter-institutional networks, but expansion of the forest stakeholders involved in such networks would further enhance adaptive capacity. In particular, it is important to network with First Nations and other forest-dependent communities who have a heightened vulnerability to climate change. The presence of a collaborative capacity builder could foster the transfer, receipt and integration of knowledge across the networks, and ultimately build long-term collaborative problem-solving capacity in the Ontario forest sector.
H. Carolyn Peach BrownEmail:
  相似文献   
816.
Recent interest in sustainable forest management planning in the Yukon has coincided with growing public awareness of climate change, providing an opportunity to explore how forestry plans are incorporating climate change. In this paper, the Strategic Forest Management Plans for the Champagne and Aishihik First Nations Traditional Territory (CATT) and the Teslin Tlingit Traditional Territory (TTTT) are examined for evidence of adaptation to climate change. For each plan, management policies and practices that are also recognized as ways to adapt to climate change are identified to provide information on the incremental costs and benefits of additional adaptation efforts. A typology for classifying sustainable forest management plans according to how they address climate change is proposed and applied to the CATT and TTTT plans. This typology, which may be useful to any future retrospective assessments on how successful these or other sustainable forest management plans have been in addressing and managing the risks posed by climate change, consists of a matrix that categorizes plans into one of four types; (1) proactive-direct, (2) proactive-indirect, (3) reactive-direct, and (4) reactive-indirect. Neither of the plans available for the southern Yukon explicitly identifies climate change vulnerabilities and actions that will be taken to reduce those vulnerabilities and manage risks. However, both plans have incorporated some examples of ‘best management practices’ for sustainable forest management that are also consistent with appropriate climate adaptation responses. Even in a jurisdiction facing rapid ecological changes driven by climate change, where there is a relatively high level of awareness of climate change and its implications, forestry planning processes have yet to grapple directly with the risks that climate change may pose to the ability of forest managers to achieve the stated goals and objectives of sustainable forest management plans.
J. L. InnesEmail:
  相似文献   
817.
While greenhouse gas (GHG) emissions are projected to rise primarily in the developing countries, the potential for developing new GHG mitigation technologies exists primarily in the industrialized countries. It is thus important, not only for predictions about future emission paths but also for climate change mitigation policies, to understand how the international diffusion of such technologies takes place and how it affects the energy infrastructure and GHG emissions in developing countries. This paper provides an overview of the channels through which these technologies diffuse and focuses on the empirical evidence pertaining to the effects these technologies have on GHG emissions in developing countries.
Sonja PetersonEmail:
  相似文献   
818.
Sex ratios of ants have been shown to vary with food resource levels in several studies, but it is not known whether forest clear-cutting has any effect on sex ratio of aphid-tending forest-dwelling ants. We investigated whether the offspring sex ratio of the forest dwelling ant Formica aquilonia varied as a response to clear-cutting. We found that the proportion of males was smaller in clear-cuts than in adjacent forests. Our results are among the first showing that anthropogenic changes in forest structures may have a potential to modify sex ratios of social insects and other forest-dwelling animals.  相似文献   
819.
我国再生锌行业二噁英污染有效控制技术探讨   总被引:1,自引:0,他引:1  
分析了我国再生锌行业产生二噁英污染的概况,为我国再生锌行业二噁英污染控制提供了基本依据;在对我国再生锌行业二噁英污染节点分析基础上,阐述了我国再生锌行业二噁英污染的控制方法;并提出了再生锌二噁英污染控制的有效技术途径.  相似文献   
820.
• Earthworms increase CO2 and N2O emissions in agricultural and forest soil. • 10% biochar suppresses CO2 and N2O emissions in forest soil. • Biochar interacted with earthworm to significant affect CO2 and N2O emissions. The application of manure-derived biochar offers an alternative to avoid the direct application of manure to soil causing greenhouse gas emission. Soil fauna, especially earthworms, can markedly stimulate carbon dioxide (CO2) and nitrous oxide (N2O) emissions from soil. This study therefore investigated the effect of cattle manure biochar (added at rates of 0, 2%, or 10%, coded as BC0, BC2 and BC10, respectively) application, with or without earthworm Aporrectodea turgida, on emissions of CO2 and N2O and changes of physic-chemical properties of agricultural and forest soils in a laboratory incubation experiment. The BC10 treatment significantly enhanced cumulative CO2 emissions by 27.9% relative to the untreated control in the agricultural soil. On the contrary, the BC2 and BC10 treatments significantly reduced cumulative CO2 emissions by 16.3%–61.1% and N2O emissions by 92.9%–95.1% compared to the untreated control in the forest soil. The addition of earthworm alone significantly enhanced the cumulative CO2 and N2O fluxes in agricultural and forest soils. Cumulative CO2 and N2O fluxes were significantly increased when BC2 and BC10 were applied with earthworm in the agricultural soil, but were significantly reduced when BC10 was applied with earthworm in the forest soil. Our study demonstrated that biochar application interacted with earthworm to affect CO2 and N2O emissions, which were also dependent on the soil type involved. Our study suggests that manure biochar application rate and use of earthworm need to be carefully studied for specific soil types to maximize the climate change mitigation potential of such management practices.  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