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   307篇
  免费   26篇
  国内免费   10篇
安全科学   6篇
废物处理   2篇
环保管理   111篇
综合类   97篇
基础理论   64篇
污染及防治   9篇
评价与监测   7篇
社会与环境   41篇
灾害及防治   6篇
  2023年   2篇
  2022年   1篇
  2021年   3篇
  2020年   1篇
  2019年   8篇
  2018年   9篇
  2017年   12篇
  2016年   18篇
  2015年   16篇
  2014年   10篇
  2013年   12篇
  2012年   21篇
  2011年   18篇
  2010年   13篇
  2009年   32篇
  2008年   21篇
  2007年   24篇
  2006年   18篇
  2005年   17篇
  2004年   14篇
  2003年   12篇
  2002年   8篇
  2001年   8篇
  2000年   6篇
  1999年   7篇
  1998年   9篇
  1997年   2篇
  1996年   5篇
  1995年   1篇
  1994年   2篇
  1993年   4篇
  1991年   4篇
  1990年   1篇
  1988年   1篇
  1985年   1篇
  1983年   1篇
  1979年   1篇
排序方式: 共有343条查询结果,搜索用时 234 毫秒
261.
This paper investigates the recreational economic value of bird watching in the Ku?cenneti National Park (KNP) at Lake Manyas, one of the Ramsar sites of Turkey and an important endangered species habitat. The lake and KNP provide considerable benefits for the region, although they have faced many environmental conflicts due to diverse stakeholders’ needs. An economic valuation for the benefits provided by the KNP is important data for stakeholders and local authorities. The travel cost method is used to estimate recreational demand for the KNP. The recreational value of the KNP is 103,320,074 USD annually. Results shed light on important policy issues and help to resolve conflicts among stakeholders. This calculated value is considerably higher than the annual investment and operation expenditures of the KNP. Sustainability of the important species around the lake could be achieved if the region's inhabitants are compensated by KNP visitors.  相似文献   
262.
This paper examines the issue of disproportionate costs of Water Framework Directive (WFD) implementation using public surveys as a means to inform policy and decision making. Public taxpayers are asked their opinion regarding the implementation of the WFD and its costs. Taxpayers are expected to bear a large share of the cost of WFD implementation, be it through national taxation, local water pollution charges or higher market prices for water related goods and services. The paper's main objective is to illustrate the role of stated preference research to elicit public opinions and perceptions towards socially acceptable levels of water quality and public willingness to pay (WTP) for the expected environmental benefits of the WFD. Stated preference research can be used as a way to assess the concept of disproportionate costs to those who are expected to bear a large share of the costs of WFD implementation, and at the same time address the issue of public participation in the WFD. The survey results are used as a public consultation tool to inform policy and decision makers about public willingness and ability to pay for the implementation of the WFD. This measure can be used as one of the benchmarks to define disproportionate costs in a cost-benefit context.  相似文献   
263.
The objectives of this study are twofold. First it aims to establish empirical grounds for pricing the services of a new environmental management initiative in Enugu state, Nigeria. A joint initiative of the UK Department for International Development (DfID), Enugu State Environmental Protection Agency (ENSEPA) and the State and Local Government Programme (SLGP). The second is to test the empirical performance of a new approach to the contingent valuation method (CVM) i.e., the Stochastic Payment Card (SPC) design proposed by Wang (Contingent valuation of environmental resources: A stochastic perspective, 1997a, Journal of Environmental Economics & Management, 32:219–232, 1997b). The SPC design unlike many of the conventional CVM elicitation formats, takes into account the stochastic nature of individuals’ valuation decisions. The data for the analysis were obtained from a random sample survey of a district in Enugu metropolis. The results show that, on average, households in this city are willing to pay (WTP) 215 Naira ($1.6) monthly as against 200 Naira ($1.5) currently charged for the service by ENSEPA. Analysis of individual’s valuation distribution function indicates that this amount is positively and significantly related to the gender of the respondent, household income and the respondent’s perception of environmental quality.
Abbi KedirEmail:
  相似文献   
264.
赵军  杨凯 《自然资源学报》2004,19(6):795-803
对自然资源产生的社会福利进行货币化计量是目前资源与环境经济学研究的焦点之一,条件估值法(CVM)在评估自然资源福利的研究方面具有独特的优势。1984年提出的基于线性效用差下福利计量的参数模型及相应的表征尺度在后来的CVM研究中得到了较多的应用,但已有研究多侧重于方法的应用,对模型和尺度的理论有效性缺乏实证性的探讨。基于随机效用最大化原理对消费者偏好函数模型及相应的福利计量尺度进行了较为详细的数学推导(以Logit模型为例)。以上海某城市河流资源CVM福利计量为例,在实证分析过程中结合国外已有研究,将线性模型与基于非线性效用差下的对数模型进行了比较,给出了在CVM研究中对自然资源进行福利计量建议采用的参数模型与表征尺度。  相似文献   
265.
条件价值法调查中会有相当比例的受访者不愿意支付费用,对这部分群体如果处理不当会影响到价值评估的可靠性和有效性。以南京市居民对长江流域生态补偿的支付意愿为例,采用双边界两分式问卷调查获取1 403份有效样本。分析了忽略零响应问题的传统模型所造成的支付意愿(Willingness to Pay,WTP)估算偏差,并采用Spike模型对WTP估算进行了校正。结果显示:若直接删除零响应样本,中位数WTP在359~396元/(户·a)之间;而将零响应的实际支付用接近零的正数进行替代,得到的中位数WTP在154~208元/(户·a)之间。根据Spike模型,将真实零响应样本纳入分析后,得到的WTP估算结果在259~288元/(户·a) 之间。表明直接删除零响应会明显高估WTP,而用零或接近零的正数替代零响应又会低估WTP。未来5 a内长江南京段的生态补偿总价值至少为24.4×108元。将决策过程划分为"加入决策"和"支付决策"两个阶段后,论文还发现,"加入决策"和"支付决策"是两种不同的机制,二者在影响因素上存在差异。此外,不同收入家庭的WTP存在明显异质性。  相似文献   
266.
生态系统服务价值研究进展   总被引:16,自引:4,他引:16  
生态系统服务价值评价结合了生态学、经济学、社会学、伦理学等学科的相关内容,是当前国际上科学研究的热点和前沿.本文论述了生态系统服务功能的内涵,就国内外生态系统服务价值评价研究的进展情况分别进行了回顾和总结,提出今后应重点关注生态系统服务价值的时空动态模型开发、时空变化驱动力分析、不确定性分析、评价指标体系与评价方法的标...  相似文献   
267.
中国自然草地生态系统服务价值   总被引:395,自引:15,他引:395  
文中参照Constaza等提出的方法,在对草地生态系统服务价格根据其生物量订正的基础上,逐项估计了各类草地生态系统的各项生态系统服务价值,得出全国草地生态系统每年的服务价值为14979×108US$。其中扰乱管理价值占1607%,水管理和水供应价值占1444%,侵蚀控制和沉积保存价值占908%,废物处理价值占4203%,授粉价值占783%,生物控制价值占72%,食物和原材料生产价值占2226%,娱乐和文化价值占578%,其它如气体管理价值、土壤形成价值和栖息地价值低于5%。受各类草地生物群落分布广度和单位面积生态服务功能强弱的综合影响,各类草地的生态服务价值贡献率有很大差异,其中,沼泽类对草地生态系统总服务价值的贡献率为5234%。温性草原类、热性草丛类、热性灌草丛类、低地草甸类和高寒草甸类对总服务价值的贡献分别在503%~774%之间,其余类型的草地生态服务价值贡献率在5%以下。  相似文献   
268.
长白山自然保护区生物多样性非使用价值评估   总被引:50,自引:0,他引:50       下载免费PDF全文
应用条件价值法(CVM),通过支付意愿(WT)调查,于1996年对长白山自然保护区生物多样性的存在价值、遗产价值和选择价值进行了实际的量化评估.调查表返回603份,反馈率64.56%,其中74.02%的反馈者愿意为保护长白山自然保护区支付费用,平均支付中位值为每人每年33.3元人民币.研究表明,该保护区生物多样性非使用价值达43.19亿元,其中存在价值为主要形式.  相似文献   
269.
山东省生态环境承载力评价指标体系探讨   总被引:3,自引:0,他引:3  
将生态环境承载力划分为资源承载力、环境承载力、循环经济水平和经济社会支持能力四部分,结合山东省生态环境现状,根据指标体系建立的原则,选用了57项评价指标,分层次构建了山东省生态环境承载力评价指标体系.其中,资源承载力选用生物资源、水资源等5大类共10项指标;环境承载力选用地表水、近岸海域等5大类共9项指标;循环经济水平选用资源产出水平、资源消耗水平等4大类共18项指标;经济社会支持能力选用人口数量与素质水平、经济发展水平等7大类共20项指标.  相似文献   
270.
Linking GIS-based models to value ecosystem services in an Alpine region   总被引:11,自引:1,他引:11  
Planning frequently fails to include the valuation of public goods and services. This can have long-term negative economic consequences for a region. This is especially the case in mountainous regions such as the Alps, which depend on tourism and where land-use changes can negatively impact key ecosystem services and hence the economy. In this study, we develop a semi-automatic procedure to value ecosystem goods and services. Several existing process-based models linked to economic valuation methods are integrated into a geographic information system (GIS) platform. The model requires the input of a digital elevation model, a land-cover map, and a spatially explicit temperature dataset. These datasets are available for most regions in Europe. We illustrate the approach by valuing four ecosystem services: avalanche protection, timber production, scenic beauty, and habitat, which are supplied by the “Landschaft Davos”, an administrative district in the Swiss Alps. We compare the impacts of a human development scenario and a climate scenario on the value of these ecosystem services. Urban expansion and tourist infrastructure developments have a negative impact on scenic beauty and habitats. These impacts outweigh the benefits of the developments in the long-term. Forest expansion, predictable under a climate change scenario, favours natural avalanche protection and habitats. In general, such non-marketed benefits provided by the case-study region more than compensate for the costs of forest maintenance. Finally, we discuss the advantages and disadvantages of the approach. Despite its limitations, we show how this approach could well help decision-makers balance the impacts of different planning options on the economic accounting of a region, and guide them in selecting sustainable and economically feasible development strategies.  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