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101.
The environment provides many necessary services for a plethora of human activities related to that are being acknowledged as our ecosystems degrade; therefore, ecosystem-based solutions are becoming increasingly more important. Hydrologic restorations (HRs) apply this type of ecosystem approach; there are multiple examples around the Mediterranean area executed since the beginning of the twentieth century. One good example of these restoration-type solutions can be seen in the badlands of Saldaña (Palencia, Spain). This case has been particularly successful in stopping gully erosion from badlands. Despite its importance for the well-being of the inhabitants of Saldaña and surroundings, the economic effects of these services which were put into place by this HR have never been assessed. In the present study, four different and compatible ecosystem restored services have been valued in monetary terms. For their aggregation, an innovative approach has been taken using the analytic hierarchy process methodology, so the weight of each ecosystem service (ES) can be determined. The economic flow of these ESs has been calculated in terms of annual income and updated values, from which natural capital increase in the population of Saldaña can be assessed. After analysing the results, it can be concluded that the village has earned more than seven million euros, which, in turn, generates important benefits to its inhabitants.  相似文献   
102.
Solid waste management in Nsukka town in Enugu state of Nigeria has remained a major challenge despite the efforts of the state government through the Enugu State Waste Management Agency (ESWAMA). The current method whereby households dump refuse at designated locations by the road side to be cleared later has not yielded much improved sanitation of the town. In this study we propose an alternative waste management method that is believed to be superior to the status quo if properly managed. This study applies Contingent Valuation Method (CVM) to estimate the households’ willingness to pay (WTP) for this new method in order to ascertain its applicability in Nsukka urban. Data were collected from a sample of 500 households stratified according to major streets in the town. The results show that the mean WTP using different specifications of the model varies from N527.50 (about 2.68) to N530.90 (about 2.68) per month. The policy implication is that if the waste management agency adopts the proposed scenario and manages it well the average revenue realizable per month would be about N13,750,516 (about $69,800). The authorities can compare this with the cost of providing the service and see if it is worth the effort.  相似文献   
103.
杨孟  钱新 《中国环境科学》2011,31(9):1563-1570
以滁州市黑洼水库的游憩价值为例,利用两边界二分式条件价值法,探讨了我国病险水库管理决策中的环境价值评估.利用收入限制的Logit模型,分析支付意愿均值和中值点估计和区间估计对其分布函数右尾变化的灵敏性.结果表明本研究中支付意愿的分布函数没有出现“大尾效应”,在最大投标值处,对分布函数进行简单截断的方法统计效率最高.滁州市公众对黑洼水库游憩功能提升的平均支付意愿为305元/户(95%置信区间265~351元/户);总价值为3782万元(95%置信区间3296~4355万元).表明即使是小型病险水库也可能具有极高的环境价值,病险水库管理决策必须考虑环境价值这一重要指标.  相似文献   
104.
污染土地价值评估问题探讨   总被引:1,自引:0,他引:1  
艾东  朱彤  乐小芳 《生态环境》2010,19(5):1253-1260
工业化和城市化为人类福利的改善作出极大的贡献,也带来了大量的污染土地。污染土地是指含有能对人身健康、环境或其它目标产生直接或间接危害的污染物的土地。污染会影响土地的价值,因此,污染土地价值评估问题近年来受到关注。文章总结了污染土地价值评估的研究进展,对关键概念进行探讨和界定,依据我国常用的几种传统土地价值评估方法,探讨如何进行修正以适应污染土地的价值评估,并对污染清理费用、环境责任费用、污名等一些关键问题进行讨论,提出污染土地的价值损失中必须考虑几个方面的不确定性:(1)与工程措施有关的清理费用的不确定性;(2)当前和未来管制要求的不确定性;(3)市场对污染损害反应的不确定性;(4)随着时间变化,市场对污染损害反应的变化。最后结合实际,说明污染土地价值评估不仅要探索新方法,也要在增加和完善环境方面的立法、进一步完善技术标准、促进学科的相互交流和发挥行业组织的主导作用等方面加强。  相似文献   
105.
我国境内石油行业总体呈现原油开采量上升的态势,为之付出的经济和生态成本也越来越大。开展我国境内石油资源资产负债表的编制工作对于摸清我国石油资源的家底、评估我国石油资源开采的经济—资源—环境综合成本、探讨我国石油开采战略的合理性具有重要的意义。本文首先探讨了石油资源资产负债表的编制方法和框架,构建了集"生态系统服务"、"环境污染"和"资源消耗"三位于一体的"生态负债"账户。其次,收集并整理了重要的污染物处理成本和生态系统服务的价值评估成果,构建了价值化因子数据表。最后,基于2012年数据尝试编制了目前我国的第一份石油资源资产负债表。结果显示,(1)2012年末,我国石油资源的资产总额为1.47×109万元,负债总额为9.03×107万元,所有者权益为1.38×109万元;(2)石油资源资产总额占到当年政府资产总额的14.43%,占政府资源性资产比重达31.12%;(3)石油行业的资产负债率为6.15%,负债权益比达到了6.56%;(4)"生态系统服务"构成了负债的最大比重,达到了98.16%。总的来说,我国石油开采行业整体处于"高资产、高负债、强生态压力和弱可持续性"的状态。从这份资产负债表我们可以看出,我国境内石油开采的生态成本不容忽视。随着资源的不断开发,石油开采的边际生态成本只会越来越大,因此,能指向经济和生态两方面的综合成本应该取代账面成本成为政府进行石油资源开发的决策依据之一。此外,要落实石油资源资产负债表对于生态保护的实际指导意义,我们建议应该将石油资源开采的资产负债率、负债权益比等指标纳入官员的绩效考核体系。  相似文献   
106.
Amenity values of private forests are implicit but play a critical role in decision and policy making. This study presents an innovative valuation approach integrating techniques of operations research and economic theory of pricing environmental goods. A forest planning problem was inversed through altering its reward function of timber values so that the observed harvesting behavior became optimal. The discrepancy between the original and new rewards uncovered amenities values which were linked to forest attributes via hedonic models. This method was applied to a case study of the U.S. southern pine region. Depending on forest conditions, total economic values of amenities varied from zero to just under one thousand dollar per ha. At a discount rate of 3%, a typically managed forest generated on average $243 ha−1 of amenities values per annum, more than twice of harvested timber values. Structural diversity and density of large pine trees were the key determinants to preserving forests for environmental amenities.  相似文献   
107.
Land reclamation significantly affects the ecological and environmental conditions of mining areas. However, quantifying the exact effects is difficult because of the lack of reliable data. The estimation of eco-environment benefit contributes to clarify the ecological and environmental changes caused by land reclamation and to provide useful information for policy-makers concerned with sustainable development. The aim of this study is to investigate variations in eco-environment benefit in response to land use changes during land reclamation. The West dump, one of the earliest regions to implement ecological restoration in Liaoning Province, is selected as the study area. The widely used methods for eco-environment benefits based on the land use change were proposed and applied to the West dump in 2004, 2009, and 2014. The total eco-environment benefits in study areas were 0.98 million dollars in 2004, 1.39 million dollars in 2009, and 1.43 million dollars in 2014, with an increase of 0.41 million dollars from 2004 to 2009 mainly because of the increasing areas of artificial woodland and reclaimed cropland. The combined eco-environment benefits of artificial woodland, improved grassland, and reclaimed cropland were over 90% of the total benefits. Soil formation and protection, biodiversity protection, and gas regulation were the top three functions with high eco-environment benefits, contributing about half of the total eco-environment benefits. The results suggest that future studies estimating eco-environment benefits should pay more attention to ecosystems in fragile ecological regions where various human interferences happen frequently. All of the abovementioned results made the techniques of estimation of the eco-environment benefit of land reclamation are more meaningful in guiding the future exploitation and reclamation of mining areas.  相似文献   
108.
Stream restoration is one of the most widely used interventions to mitigate urban stormwater impacts and improve water quality. Government agencies have typically focused urban stream restoration efforts on public lands that they already own, even though a substantial portion of stream miles in highly urbanized areas occur on privately owned land. Yet, limited research exists to distinguish household willingness to pay (WTP) for stream restoration occurring on private versus public land. In this study, we use a choice experiment to analyze how household WTP for stream restoration attributes vary by land ownership and distance to the restoration project. Our empirical results indicate that streambank stabilization approaches have positive WTP estimates that are substantially larger in magnitude than those related to riparian vegetation management for clearing or planting trees. In general, estimated total household WTP for each of the four restoration design scenarios on public land is higher than when the same restoration design is located on private land. Nonetheless, estimated household WTP for each restoration design scenario on private land is substantial, retaining the majority of the value found on public land in all cases.  相似文献   
109.
石油农业导致生态系统退化与环境受损.人们在寻找新的农业途径时,将目光转向传统农业,开始对传统农耕模式的价值进行挖掘.稻鱼共生是最为典型的中国传统生态农业模式之一,因其历史悠久、景观独特和效益显著而被联合国粮农组织列为首批全球重要农业文化遗产保护试点之一.在数千年的农耕文化演变过程中,同宗的青田县和从江县的传统农业系统,由于受到不同的自然、经济和文化的影响,分别形成了以养鱼为主和以种稻为主的稻鱼共生系统.本文采用市场价值法、造林成本法、替代价格法、大气污染治理成本法和水库工程费用法等,分别对青田县和从江县传统农业区生态系统服务功能的经济进行评估.结果表明,以养鱼为主的青田县直接经济价值比以种稻为主的从江县平均每公顷高近1.70万元,但其闻接价值却比后者低,从江县稻鱼共生系统的气体调节和养分保持价值分别是青田县的1.35和1.59倍.最后,本文提出了提高农民收入的途径,以更好地保护这一具有全球重要意义的农业文化遗产.  相似文献   
110.
Air quality assessment by contingent valuation in Ji'nan, China   总被引:1,自引:0,他引:1  
Along with urbanization and environmental deterioration within China, many residents' desire for improved air quality has increased. To address this topic, this study focuses on the relationship between poor air quality and residents' willingness to pay for improved air quality in the city of Ji'nan. As a means of quantifying an individual's willingness to pay (WTP) for improved air quality, a contingent valuation method (CVM) was employed. A sample of 1500 residents was chosen, based on the stratified sampling method. The respondents' WTP was then elicited through a series of face-to-face interviews, conducted using a range of hypothetical, open-ended scenario questions. The results showed that 59.7% of respondents were able to express a positive WTP, and that the average WTP was 100 Chinese Yuan (CNY) per person, per year. In order to establish the relationship between endogenous variables and WTP, both a Probit model on the probability of a positive WTP, and a stepwise regression model were constructed. Most parameters in the econometric analysis demonstrated the expected results. It was found that annual household income, expenditure on the treatment of respiratory diseases and workers in the family significantly influenced WTP. The rates of positive WTP and the monetary amount were also larger for men than for women. Unlike developed countries, most respondents regard air quality improvement as a government responsibility in that more than 40% of respondents had no incentive to bear the costs of attempting to achieve better air quality, indicating a relatively low environmental consciousness.  相似文献   
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