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   1936篇
  免费   164篇
  国内免费   49篇
安全科学   38篇
废物处理   27篇
环保管理   913篇
综合类   451篇
基础理论   291篇
环境理论   44篇
污染及防治   49篇
评价与监测   33篇
社会与环境   231篇
灾害及防治   72篇
  2024年   8篇
  2023年   35篇
  2022年   23篇
  2021年   50篇
  2020年   55篇
  2019年   92篇
  2018年   79篇
  2017年   152篇
  2016年   113篇
  2015年   85篇
  2014年   66篇
  2013年   121篇
  2012年   85篇
  2011年   109篇
  2010年   60篇
  2009年   101篇
  2008年   82篇
  2007年   70篇
  2006年   77篇
  2005年   75篇
  2004年   54篇
  2003年   48篇
  2002年   64篇
  2001年   55篇
  2000年   58篇
  1999年   45篇
  1998年   31篇
  1997年   26篇
  1996年   25篇
  1995年   31篇
  1994年   19篇
  1993年   19篇
  1992年   12篇
  1991年   8篇
  1990年   15篇
  1989年   9篇
  1988年   7篇
  1987年   7篇
  1986年   9篇
  1985年   17篇
  1984年   8篇
  1983年   9篇
  1982年   6篇
  1981年   5篇
  1979年   4篇
  1978年   4篇
  1977年   5篇
  1973年   2篇
  1972年   2篇
  1971年   3篇
排序方式: 共有2149条查询结果,搜索用时 171 毫秒
331.
A carbon tax on fuel would penalize carbon intensive fuels like gasoline and shift fuel consumption to less carbon intensive alternatives like biofuels. Since biofuel production competes for land with agricultural production, a carbon tax could increase land rents and raise food prices. This paper analyzes the welfare effect of a carbon tax on fuel consisting of gasoline and biofuel in the presence of a labor tax, with and without a biofuel subsidy. The market impacts of a carbon tax are also compared with that of a subsidy. Findings show that if a carbon tax increases biofuel demand, the tax interaction effect due to higher fuel prices is exacerbated by higher land rent and food prices and greater erosion of the carbon tax base. Thus, the second best optimal carbon tax for fuel is lower with biofuel in the fuel mix, especially if biofuel is subsidized.  相似文献   
332.
国家水污染防治“十二五”战略与政策框架   总被引:5,自引:0,他引:5       下载免费PDF全文
为对我国"十二五"水污染防治工作的宏观部署提供支持,在剖析水污染防治内涵的基础上,深入分析了"十二五"形势,明确了"十二五"总体定位,提出了包含水污染物排放总量、水环境质量和水生态在内的目标指标体系,以"削减总量-改善质量-防范风险"为主线,设计了加强饮用水水源保护等6项战略任务,制定了基于"流域-控制区-控制单元"三级分区体系实施分级防治和分类指导的空间战略,较全面地列出了保障水污染防治工作有序开展的政策、法规和制度,从而描绘出我国"十二五"水污染防治的战略与政策框架,可为"十二五"水污染防治规划编制等工作及相关管理决策提供参考.  相似文献   
333.
Over the past several decades a growing interest has emerged in the relationship between forest dependent communities and their use of non-timber forest resources (NTFR—i.e. berries, roots, barks). Motivated in large part by international concerns over the loss of biological and cultural diversity, efforts are now being made to conserve the world's remaining forests by repositioning NTFR to the forefront of the forest management process. Together with the Little Salmon Carmacks First Nation, we have undertaken an assessment that: 1) addresses the role of NTFR in fulfilling basic human necessities and well-being of community members, and 2) identifies the perceptual differences that exist among First Nation and non-First Nation community members regarding the security and future availability of forest resources. Based on our findings, we argue that if the true value of the forest is to be understood, and thus sustained, those involved in management must consider the full array of products and services the forest provides. Thus the conventional and over-simplified view that the forest is to provide primarily for commercial timber must be challenged in light of the multiplicity of values community members gain from forest use.  相似文献   
334.
SUMMARY

Whilst the world economy is developed, the life and development of human beings have been threatened by the imbalance between environmental and ecological aspects. Thus, sustainability is becoming increasingly the focus of various social fields. For most developing countries, a strategy with good sustainability for social development is of long-term significance to keep the economy in expansion. This paper first reviews the conceptual framework and up-to-date development of sustainability. Second, it reviews the current transport situation of China and its future demands. Third, the paper analyses transport policy from the viewpoints of energy consumption and environment pollution caused by transportation. It finally summarises suggestions for transport policy that China should consider in the future.  相似文献   
335.

India and Canada share a common heritage in natural resources management. Both have a colonial background, settlers and indigenous peoples; there is a history of management agencies with utilitarian attitudes, and a history of treating public lands as commodities for commerce rather than as resources for local livelihoods. This historical context guided the overall goal of this study, which was policy development for the sustainable use of mountain environments. Interviews, workshops and seminars were held with local people and resource management professionals in a comparative case study in two regions; the Kullu area in Himachal Pradesh, India and the Arrow Lakes area in British Columbia, Canada. The paper is organized around two main objectives of the work relating to the successes and failures of mountain environment resource management policies and the development of criteria for assessing and monitoring sustainability in mountain environments, in particular, criteria for examining relevant crosscultural dimensions of sustainable development in these environments. By way of conclusion the paper considers further ways in which traditional resource policy development and implementation is being challenged by changing values and priorities; ecosystems management with people; and co-management and public participation.  相似文献   
336.
This article presents a system dynamics (SD) method to examine the problem of forest degradation. The model developed takes a system-oriented view of forest management, embracing both social and biophysical factors affecting deforestation. Social factors examined are socio-economic variables or elements that influence behaviour and decision-making choices at the household level. Biophysical factors are four sub-components that are considered major land uses namely, the paddy field component, rattan plantations, coffee plantations and forest stands. The model was applied in a case study located in Pasir District of East Kalimantan, Indonesia. The site covers an area that includes a protected forest and a privately allocated timber license concession. Three village communities are examined in the case study. The SD model developed was applied to the case study focusing on three management policies or scenarios, which are based on access rights to the forest resources within the study area. Specifically, the property arrangements examined in each scenario are: Policy 1 – status quo (i.e. continue present property rights arrangements); Policy 2 – local communities manage the forest exclusively; and Policy 3 – collaborative management involving both local communities and a private company. Results from the model show that the third policy is the most viable option, and also lead to a win–win solution.  相似文献   
337.
This study aims to identify services provided by forest ecosystems based on locals’ perceptions in the northern part of Jordan. By better understanding preferences of locals and by understanding why they value certain services more heavily, policy-makers and planning managers can make more effective decisions regarding development and conservation. Three hundred respondents were interviewed in order to collect information about forest ecosystem services (ES). Data collection was conducted using a structured questionnaire regarding ES provided by three forest types situated in northern Jordan. ES trade-offs and socio-ecological bundles were identified by analyzing respondents’ socioeconomic demographics and preferences of forest ES through multivariate canonical corresponding analysis (CCA). The statistical analysis indicated that the socioeconomic factors and forest type have an effect on social preferences toward ES. Results displayed a clear trade-off between provisioning services and regulating and cultural services. CCA demonstrated that 73% of the variation in ES value is explained by social factors (i.e. education level, income level, and gender), while 26% of perception variation was attributable to categories of ES supplied by each forest ecosystem. These findings imply that involving people in the place-specific management of public forests using the ES approach gives managers a clearer understanding of the benefits people recognize and value, as well as those they either are not aware of or do not value. Such information is useful in forest management and in public outreach. Although direct policy applications are limited by the research’s nature, the paper provides a starting point for incorporating forest users’ voices into policy discussions and management design.  相似文献   
338.
Some conservation initiatives provoke intense conflict among stakeholders. The need for action, the nature of the conservation measures, and the effects of these measures on human interests may be disputed. Tools are needed to depolarize such situations, foster understanding of the perspectives of people involved, and find common ground. We used Q methodology to explore stakeholders' perspectives on conservation and management of grizzly bears (Ursus arctos horribilis) in Banff National Park and the Bow River watershed of Alberta, Canada. Twenty-nine stakeholders participated in the study, including local residents, scientists, agency employees, and representatives of nongovernmental conservation organizations and other interest groups. Participants rank ordered a set of statements to express their opinions on the problems of grizzly bear management (I-IV) and a second set of statements on possible solutions to the problems (A-C). Factor analysis revealed that participants held 4 distinct views of the problems: individuals associated with factor I emphasized deficiencies in goals and plans; those associated with factor II believed that problems had been exaggerated; those associated with factor III blamed institutional flaws such as disjointed management and inadequate resources; and individuals associated with factor IV blamed politicized decision making. There were 3 distinct views about the best solutions to the problems: individuals associated with factor A called for increased conservation efforts; those associated with factor B wanted reforms in decision-making processes; and individuals associated with factor C supported active landscape management. We connected people's definitions of the problem with their preferred solutions to form 5 overall problem narratives espoused by groups in the study: the problem is deficient goals and plans, the solution is to prioritize conservation efforts (planning-oriented conservation advocates); the problem is flawed institutions, the solution is to prioritize conservation efforts (institutionally-oriented conservation advocates); the problems have been exaggerated, but there is a need to improve decision-making processes (optimistic decision-process reformers); the problems have been exaggerated, but managers should more actively manage the landscape (optimistic landscape managers); and the problem is politicized decision making, solutions vary (democratizers). Although these 5 groups differed on many issues, they agreed that the population of grizzly bears is vulnerable to extirpation, human use of the area should be designed around ecological constraints, and more inclusive decision-making processes are needed. We used our results to inform a series of workshops in which stakeholders developed and agreed on new management strategies that were implemented by Parks Canada. Our research demonstrates the usefulness of Q method to illuminate people's perspectives and identify common ground in settings where conservation is contested.  相似文献   
339.
Policy advocacy is an issue regularly debated among conservation scientists. These debates have focused on intentional policy advocacy by scientists, but advocacy can also be unintentional. I define inadvertent policy advocacy as the act of unintentionally expressing personal policy preferences or ethical judgments in a way that is nearly indistinguishable from scientific judgments. A scientist may be well intentioned and intellectually honest but still inadvertently engage in policy advocacy. There are two ways to inadvertently engage in policy advocacy. First, a scientist expresses an opinion that she or he believes is a scientific judgment but it is actually an ethical judgment or personal policy preference. Second, a scientist expresses an opinion that he or she knows is an ethical judgment or personal policy preference but inadvertently fails to effectively communicate the nature of the opinion to policy makers or the public. I illustrate inadvertent advocacy with three examples: recovery criteria in recovery plans for species listed under the U.S. Endangered Species Act, a scientific peer review of a recovery plan for the Northern Spotted Owl (Strix occidentalis caurina), and the International Union for Conservation of Nature's definition of threatened. In each example, scientists expressed ethical judgments or policy preferences, but their value judgments were not identified as such, and, hence, their value judgments were opaque to policy makers and the public. Circumstances suggest their advocacy was inadvertent. I believe conservation scientists must become acutely aware of the line between science and policy and avoid inadvertent policy advocacy because it is professional negligence, erodes trust in scientists and science, and perpetuates an ethical vacuum that undermines the rational political discourse necessary for the evolution of society's values. The principal remedy for inadvertent advocacy is education of conservation scientists in an effort to help them understand how science and values interact to fulfill the mission of conservation science.  相似文献   
340.
中国不断发生的重大环境突发事故使得环境风险管理提上了政府的议事日程,建立有效和实用的环境风险管理体系势在必行。近年来,风险地图已成为环境风险管理中迅速崛起的新领域。风险地图不但可以探讨污染物效应的空间特征,而且可作为风险可视化的重要工具。通过调研和分析大量文献,在描述了环境风险地图的功能、重要的风险地图类型基础上,以一个城市为例展示了风险图制作流程,最后,对环境风险地图在中国的应用和发展提出了建议。  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