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   111篇
  免费   3篇
  国内免费   1篇
安全科学   11篇
废物处理   1篇
环保管理   51篇
综合类   15篇
基础理论   24篇
污染及防治   4篇
评价与监测   4篇
社会与环境   4篇
灾害及防治   1篇
  2023年   2篇
  2022年   1篇
  2021年   2篇
  2020年   2篇
  2019年   1篇
  2018年   1篇
  2017年   2篇
  2016年   5篇
  2015年   1篇
  2014年   1篇
  2013年   3篇
  2012年   6篇
  2011年   17篇
  2010年   3篇
  2009年   11篇
  2008年   4篇
  2007年   2篇
  2006年   6篇
  2005年   4篇
  2004年   4篇
  2003年   5篇
  2002年   2篇
  2000年   3篇
  1999年   1篇
  1998年   2篇
  1997年   2篇
  1995年   2篇
  1994年   1篇
  1992年   1篇
  1990年   2篇
  1989年   2篇
  1987年   1篇
  1986年   1篇
  1985年   2篇
  1984年   2篇
  1983年   1篇
  1980年   2篇
  1977年   1篇
  1976年   1篇
  1975年   1篇
  1973年   1篇
  1971年   1篇
排序方式: 共有115条查询结果,搜索用时 15 毫秒
31.
There have been no published performance evaluations of nongovernmental, voluntary habitat stewardship programs. The Operation Burrowing Owl (OBO) stewardship program, initiated in 1987, was evaluated for its effectiveness in conservation of grassland habitat during 1986–1993. The 108 OBO sites from 1987 to 88 and 98 randomly selected non-OBO sites that were grassland in 1986 in the Regina-Weyburn, Saskatchewan study area were classified by size and agricultural soil suitability. By 1993, 41 (38%) of the 108 OBO sites had been withdrawn from the program. The 1986 area of grassland was compared with grassland area calculated from digitized 1993 LANDSAT imagery. A correction for satellite inaccuracies was determined. Grassland retention in 1993 was significantly higher at OBO sites (66%) than at random sites (49%), demonstrating that the OBO voluntary program effectively conserved habitat. Also, grassland retention was significantly lower on sites with better agricultural soils, and for sites <12 ha in size. Site type (OBO or random), size and their interaction, followed by agricultural soil suitability, had the greatest effects on grassland retention. During an era of accelerated grassland loss, OBO strongly and positively (statistically significant) affected conservation of grassland sites most at risk: sites <12 ha in size and with good to excellent agricultural soils. This suggests that grassland conservation efforts focus on vulnerable sites (small size and/or good agricultural soils) to provide nesting habitat for burrowing owls. Our study demonstrates that a voluntary stewardship program can significantly increase conservation of habitat.  相似文献   
32.
An econometric model was developed to measure the influence of several environmentally oriented variables and an ownership variable upon the average total residential water costs for New Hampshire water systems. The implementation of leak detection programs, localized institutional rules and regulations, and hazardous waste inspection programs were statistically significant in influencing residential water costs. The existence of a water conservation program did not statistically influence these per unit costs. Water systems that were privately owned resulted in per unit costs that were higher relative to firms that were publicly owned.  相似文献   
33.
Although various studies have shown thatfarmers believe there is the need for a producer-ledinitiative to address the environmental problems fromagriculture, farmers in several Canadian provinceshave been reluctant to widely participate inEnvironmental Farm Plan (EFP) programs. Few studieshave examined the key issues associated with adoptingEFP programs based on farmers', as opposed to policymakers', perspectives on why producers are reluctantto participate in the program. A study adapting VanRaaij's (1981) conceptual model of the decision-makingenvironment of the firm, and prospect theory on valuefunctions associated with the gains and losses fromrisky choices can be used to characterize how farmersperceive potential risks in environmental farmplanning. This framework can be used to assert thatfarmers are concerned about risks of public disclosureof potentially incriminating environmental informationfrom farms because the EFP program requirements foridentification and extensive documentation of farminformation is perceived by farmers as facilitatingthe accessibility of environmental information to thepublic, and public investigative efforts. Although theEFP program does not explicitly generate informationabout the environmental conditions of a farm nor thedisclosure of such information to the public, itcreates the possibility of generating and divulgingpotentially incriminating information that the farmermay want to treat as confidential. Yet, alone, theserisks of public disclosure concerns should not preventfarmers from participating in the EFP. Awareness ofand participation in environmental farm planning canbe increased if farmers and policy makers understandwhat the risks are, and how they arise. Aspects of theEFP process that have the potential to generate riskof public disclosure concerns relate to farm reviews,documentation and record keeping, and correctiveaction plans. There are legal and policy instrumentsthat can offer various forms of protection and helpminimize such risks, and these need to be assessed.  相似文献   
34.
Some countries, including Taiwan, have adopted strategic environmental assessment (SEA) to assess and modify proposed policies, plans, and programs (PPPs) in the planning phase for pursuing sustainable development. However, there were only some sketchy steps focusing on policy assessment in the system of Taiwan. This study aims to develop a methodology for SEA in Taiwan to enhance the effectiveness associated with PPPs. The proposed methodology comprises an SEA procedure involving PPP management and assessment in various phases, a sustainable assessment framework, and an SEA management system. The SEA procedure is devised based on the theoretical considerations by systems thinking and the regulative requirements in Taiwan. The positive and negative impacts on ecology, society, and economy are simultaneously considered in the planning (including policy generation and evaluation), implementation, and control phases of the procedure. This study used the analytic hierarchy process, Delphi technique, and systems analysis to develop a sustainable assessment framework. An SEA management system was built based on geographic information system software to process spatial, attribute, and satellite image data during the assessment procedure. The proposed methodology was applied in the SEA of golf course installation policy in 2001 as a case study, which was the first SEA in Taiwan. Most of the 82 existing golf courses in 2001 were installed on slope lands and caused a serious ecological impact. Assessment results indicated that 15 future golf courses installed on marginal lands (including buffer zones, remedied lands, and wastelands) were acceptable because the comprehensive environmental (ecological, social, and economic) assessment value was better based on environmental characteristics and management regulations of Taiwan. The SEA procedure in the planning phase for this policy was completed but the implementation phase of this policy was not begun because the related legislation procedure could not be arranged due to a few senators’ resistance. A self-review of the control phase was carried out in 2006 using this methodology. Installation permits for 12 courses on slope lands were terminated after 2001 and then 27 future courses could be installed on marginal lands. The assessment value of this policy using the data on ecological, social, and economic conditions from 2006 was higher than that using the data from 2001. The analytical results illustrate that the proposed methodology can be used to effectively and efficiently assist the related authorities for SEA.  相似文献   
35.
This study uses California data to compare redevelopment for properties subject to mandatory and voluntary cleanup. CalSites are subject to the CERCLA liability approach, while properties in the Voluntary Cleanup Program (VCP) are subject to a risk-based approach (RBA) that allows some contamination to remain for non-residential redevelopment. The expectation is that VCPs will show a greater proportion of industrial redevelopment, which has the least stringent standard, and a smaller proportion of residential redevelopment. The results show an overall trend toward more residential redevelopment of contaminated properties, but consistent with expectations, the trend is weaker for VCP properties than CalSites.  相似文献   
36.
PROBLEM: Safety belt use rates among front seat occupants of passenger vehicles are substantially lower at night than during the day despite the fact that night driving is more dangerous. METHOD: Recent advances in night vision equipment now make it possible to enforce belt use laws in darkness. Reading, Pennsylvania conducted a night belt use publicity and enforcement campaign during September 2004 using night vision equipment. RESULTS: Front seat occupant belt use at night increased significantly from 50% prior to the campaign to 56% just after the campaign. Daylight belt use also increased though to a lesser extent (56% to 59%). Survey data indicated that motorists had heard about the campaign in newspapers and on television. Belt use increases were not seen during the same time period in a comparison community.  相似文献   
37.
安全工程专业学历教育方案的中西对比研究   总被引:8,自引:12,他引:8  
根据学科研究对象的异同 ,对中外不同名称的安全科学技术学科领域间对应关系的分析表明 ,我国的安全科学技术学科与美国、英国等西方国家称为公共健康的学科 ,我国的安全工程与西方国家的职业安全健康学科分别在宽泛和具体的意义上基本对应 ,相应的学历教育方案具有可比性。以此为据 ,运用案例比较研究了安全工程与职业安全健康学科专业学历教育方案中课程设置的多方面差别 ,分析了通过改善学历教育方案、加强职业安全培训途径来提高我国安全管理水平的努力方向。  相似文献   
38.
Terrascope is a freshman learning community at the Massachusetts Institute of Technology (MIT) in which teams of students work to find solutions to large ‘unsolvable’ problems and to communicate about those problems with a wide variety of audiences in multiple formats. The program strongly promotes students’ autonomy in focusing and structuring their work, and student projects culminate in public presentations, both to general audiences and to panels of technical specialists. Students who have completed the program tend to show strong engagement with environmental and sustainability issues, as well as the skills and experience to work intensively on such issues within multidisciplinary teams. Here, we present the program as a case study, with some discussion of the factors that are key to its operation.
Ari W. EpsteinEmail:
  相似文献   
39.
The protection of wetlands and riparian areas has emerged as an important environmental planning issue. In the United States, several federal and state laws have been enacted to protect wetlands and riparian areas. Specifically, the federal Clean Water Act includes protection requirements in Sections 301 and 303 for state water quality standards, Section 401 for state certification of federal actions (projects, permits, and licenses), and Section 404 for dredge and fill permits. The Section 401 water quality state certification element has been called the “sleeping giant” of wetlands protection because it empowers state officials to veto or condition federally permitted or licensed activities that do not comply with state water quality standards. State officials have used this power infrequently. The purpose of this research was to analyze the effectiveness of state wetland and riparian programs. Contacts were established with officials in each state and in the national and regional offices of key federal agencies. Based on interviews and on a review of federal and state laws, state program effectiveness was analyzed. From this analysis, several problems and opportunities facing state wetland protection efforts are presented.  相似文献   
40.
Abstract:  Many endangered species depend on certain types of agricultural or other forms of human land use. To conserve such species, schemes are set up in which land users receive payments for voluntarily managing their land in a biodiversity-enhancing manner. We developed a model-based framework for designing cost-effective payment schemes that generate spatiotemporal habitat heterogeneity to maximize the survival of multiple species under budget constraints. The framework integrates ecological and economic knowledge and consists of the derivation of an ecological benefit function and a budget function that are then combined to determine the cost-effective degree of spatiotemporal habitat heterogeneity. The ecological benefit function considers the timing of conservation measures, the induced habitat dynamics, and different degrees of substitutability among species. The budget function considers that the conservation agency may lack information about land users' individual conservation costs and personal attitudes and that land users can choose among different conservation measures. We applied the framework to a case study of grassland management, where the survival of three endangered species protected by the EU Habitats Directive depends on different types of land use. The lack of information available to the agency and the choice options of land users reduced the amount of conservation that can be financed with a given budget. Neglecting such findings may lead to an overestimation of the benefits of conservation programs.  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