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   173篇
  免费   2篇
  国内免费   9篇
安全科学   5篇
环保管理   92篇
综合类   27篇
基础理论   20篇
污染及防治   10篇
评价与监测   15篇
社会与环境   10篇
灾害及防治   5篇
  2022年   1篇
  2021年   2篇
  2020年   2篇
  2019年   3篇
  2018年   5篇
  2017年   7篇
  2016年   7篇
  2015年   6篇
  2014年   5篇
  2013年   16篇
  2012年   2篇
  2011年   10篇
  2010年   5篇
  2009年   11篇
  2008年   9篇
  2007年   8篇
  2006年   12篇
  2005年   4篇
  2004年   2篇
  2003年   4篇
  2002年   5篇
  2001年   3篇
  2000年   6篇
  1999年   1篇
  1998年   4篇
  1997年   3篇
  1995年   2篇
  1994年   2篇
  1993年   4篇
  1992年   1篇
  1991年   2篇
  1989年   1篇
  1988年   2篇
  1987年   1篇
  1986年   2篇
  1985年   1篇
  1984年   4篇
  1983年   3篇
  1982年   3篇
  1981年   3篇
  1980年   6篇
  1979年   1篇
  1978年   1篇
  1977年   1篇
  1973年   1篇
排序方式: 共有184条查询结果,搜索用时 31 毫秒
21.
加拿大在资源环境宏观管理的经验和成就是多方面的 ,最重要的是政府支持 ,坚持实施可持续发展战略 ,要求各部门围绕这个中心制订相关的支持和激励政策 ,推动清洁生产的实施。作者在借鉴加拿大经验基础上 ,对我国的资源环境管理提出若干建议。  相似文献   
22.
How do people think about the physical setting in the world around them? Part of the answer to this question may be in terms of the behaviors that occur there. To explore people's knowledge of behavior—place associations, twenty places (shown via color photographs) were assessed in five ways: (a) ratings of the place's suitability for each of eleven behaviors, (b) ratings of the expected frequency of occurrence of the eleven behaviors, (c) free listings of reasons for going to each place, (d) free listings of activities-while-there and (e) free listings of activities associated with the place. Results showed that people can distinguish places on the basis of behaviors, that the behavioral component of place meaning is composed of distinct aspects, and that knowledge of behavior is related to a global, overall representation of a place.  相似文献   
23.
Once the ‘risk’ of the industry is recognized, there are at least two sources of higher-than-normal returns to investment in mineral extraction: Ricardian rents to resources with different economic qualities and monopoly rents. An estimate of the relative importance of these sources in the Canadian nickel industry over the period 1961-74 is made and it is found that Ricardian rents and, for one firm, monopoly rents, were important.  相似文献   
24.
/ The paper investigates how the Canadian nonferrous sector is tackling the challenge of sustainable development. Although there is no consensus as to what sustainable development means in practice for management in the sector, at least three dimensions must be taken into account: (1) metals are recyclable, the availability of this resource is not a concern for the foreseeable future; (2) the need to minimize environmental impacts of metals exploration, extraction, transformation, consumption, and recycling; and (3) production activities should not be socially or culturally disruptive. The nonferrous mining industry faces several environmental problems. Some of the most significant are acid mine drainage, sulfur emissions, recycling, and metals toxicity. The industry has developed a number of responses to address these specific concerns as well as other more general challenges. Six strategies are described and analyzed: (1) research and development, (2) an effort of consensus building among stakeholders known as the Whitehorse Mining Initiative, (3) international networking, (4) active involvement in the development of environmental management standards, (5) management reorganization and (6) voluntary agreements. The importance of external factors in the shaping of corporate environmental management practices is discussed, in particular the role of government. Progress has been achieved in three areas: (1) managerial practices and organization, (2) reducing the impacts of ongoing operations and (3) minimizing future liabilities, but two significant fields of conflict remain, namely mining in wilderness areas and projects on aboriginal lands.KEY WORDS: Canada; Environmental management; Minerals industry; Nonferrous metals; Sustainable development; Whitehorse Mining Initiative  相似文献   
25.
西北冰洋海域表层沉积物中厌氧菌分布特征   总被引:1,自引:0,他引:1  
用逐步稀释法在4℃和25℃培养条件下测定了西北冰洋海域24个表层沉积物样品中厌氧菌(Anaerobic bacteria,AAB) 的检出率和含量.同时,分析了这两项指标的水平分布(纬度间、经度间)差异,以及在不同水深的变化特征.结果表明,在4℃和25℃培养条件下厌氧菌检出率高达100%,AAB含量范围分别为9.00×102~2.40×107cell·g-1和2.90×104~2.40×107cell·g-1,平均含量分别为4.54×106cell·g-1和3.99×106cell·g-1.AAB含量存在水平分布差异,随着纬度升高,或经度自西向东,或水深的加大,AAB的含量均呈现逐渐降低的趋势.  相似文献   
26.
In the spring and summer of 2017, communities along the Lake Ontario shoreline suffered from the worst flood event on record. In late May, daily water levels reached their highest point in over 100 years, and flooding continued throughout much of the summer as lake levels slowly declined, with inundation and erosion significantly impacting shoreline homes and businesses. In this work, we present results from a rapid response online survey of property owners along the New York Lake Ontario shoreline to quantify the perceived flood impacts of the 2017 extended high water event. The survey focused on the degree and spatial distribution of inundation and erosion; the duration and drivers of inundation; the associated damages to different property features, with an emphasis on shoreline protection; and the degree of disruption to business and other activities and services. Photographic documentation of inundation extent and property damage also was provided by survey respondents. We demonstrate the potential utility of this dataset by characterizing key features of inundation and erosion impacts across the shoreline, and by using classification and regression trees to explore the predictability of inundation and erosion based on property characteristics. This work is part of a larger effort to develop models of inundation and erosion that can support flood impact assessments across the shoreline and help communities better prepare for future extended high water events.  相似文献   
27.
Large crowds in parks can be a problem for park managers and visitors. However, perceptions of crowding are difficult to measure due to coping mechanisms deployed by park visitors. Furthermore, perceptions of crowding should not be measured in isolation, but rather as part of a suite of conditions that comprise the visitors’ outdoor experience. We used a dichotomous choice experiment with visual images and eight attributes to estimate park users’ utilities associated with their visitor experience in Garibaldi Provincial Park in British Columbia, Canada. Our visual method allowed us to control for background view and compare user preferences on hiking trails with preferences at final destinations. We find that utilities are more sensitive to crowding at viewpoints than to other aspects of the outdoor experience. Thus, visitor satisfaction and crowding perceptions are more likely to be defined by where visitors have these encounters rather than the total number of encounters.  相似文献   
28.

Recognizing the limitations common to both centralized and privatized management regimes, institutionalized resource management is beginning to incorporate the knowledge and skills of local resource users, coupled with the enabling policies and legislation of state systems, to arrive at cooperative approaches to resource management. These varying and dynamic approaches to resource management have been compelled largely through the recognition of the limited capabilities of existing management systems to adapt effectively to ecosystem change and the evolving needs of resource users. These cooperative approaches to management should not, however, be considered an institutional end-point, but rather a phase in the perpetual transition of a social system; each unique in character and individually variable depending on the resource being managed, the political climate in which management occurs, as well as the differing strategies employed by resource users to enact institutional change. Drawing from the experiences of the Whitefish Lake First Nation of Alberta, Canada, this paper presents a brief overview of the evolution of resource management theory, grounded in the real-world formation of the Whitefish Lake First Nation — Province of Alberta Cooperative Management Agreement.  相似文献   
29.
加拿大最佳管理措施流域评价项目评述   总被引:1,自引:0,他引:1  
可持续农业的目的是在保持良好环境质量的同时获得较高的农业生产率。最佳管理措施(BMPs)在世界范围内已得到广泛应用,以减少农业污染物对水环境的影响。自2004年以来,加拿大农业部实施了最佳管理措施流域评价(WEBs)项目,在全国各地选择了有代表性的9个小流域,对BMPs的环境和经济效益进行评价。笔者对过去几年来WEBs项目的进展、研究方法及主要成果进行简要的回顾,并对在中国开展类似项目的必要性和启示进行了探讨。  相似文献   
30.
Some scholars and activists have suggested that discourses of environmental sustainability do not include sufficient attention to social issues or environmental justice. Since social inclusion is a prevalent masterframe among activists and in social policy circles in Canada and elsewhere, our research explored the extent that English-speaking Canadian environmental non-governmental organisations (ENGOs) incorporate discursive aspects of social inclusion into their website communication. Social inclusion includes such issues as multiculturalism, gender inequality, low income and racialisation. We analysed mission statements, programmes and policy analysis presented by a sample of ENGOs drawn from the membership of the Canadian Environmental Network for evidence of a variety of indicators of attention to social inclusion. We conclude that environmental groups remain locked into an “environmentalist” frame that often ignores such issues. This has major implications for partnerships with other Canadian social movements.  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