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51.
Opportunity costs can represent a significant portion of the costs associated with conservation projects and frequently outstrip other kinds of cost. They are typically understood to refer to the benefits someone would have obtained if conservation projects had not required them to give up current activities, such as farming or hunting or if the land had been available for uses other than conservation. This familiar way of identifying opportunity costs is flawed, however, because it threatens to condone, or take advantage of, the injustices that many people face that affect their opportunities. I integrated ideas from the political theory of global justice to examine how the analysis of opportunity costs illustrates the importance of considering conservation and issues of global justice together, rather than thinking about them in isolation. I distinguish four baselines for defining opportunity costs. A status quo baseline defines opportunity costs by asking what people would have earned had a conservation project not happened. A willingness to accept baseline defines them by asking people what it would take to make them indifferent to whether a conservation project takes place or not. An antipoverty baseline suggests that opportunity costs have been met when people affected by a project are not left in poverty. An egalitarian baseline suggests opportunity costs have been met when people are not left in relative disadvantage, with worse than average opportunities. I argue that the egalitarian baseline is the most acceptable from the point of view of justice. Such a baseline would suggest that, in practice, many of the world's poor are being unjustly treated, or even exploited, as a result of conservation activities.  相似文献   
52.
In cost-benefit analysis, natural resources, like other factors of production, should be costed as a mixture of marginal social cost of exploiting additional resources and lost marginal social benefit of forgone alternative uses, according to the way in which extra resources are made available to a project. For a nonrenewable resource, changes in future marginal social cost and marginal social benefit are likely to add significantly to the immediate elements of cost, as successively less tractable resource stocks are exploited. Of the several reasons given for ignoring these future costs, the most plausible is that technological advance justifies a heavy discount on the future. However, neither historical nor logical arguments demonstrate the inevitability of efficacious technological advance.  相似文献   
53.
One of the most pressing problems facing wilderness managers in the ecologically fragile Drakensberg Mountains, South Africa, is that of path erosion, since it detracts from the wilderness experience and is very costly to remediate. As increasing demand for wilderness and outdoor recreation places greater pressure on paths and trails, it will be necessary to increase path network size and capacity, and it is important that new paths are routed such that maintenance requirements are minimal. This study describes the development of a technique based on the site and environmental variables of rainfall, topographic slope, and lithology, which enables assessment of path erosion risk before paths are planned and constructed. The technique was tested on a path at the Drakensberg resort of Loteni, and showed good correlation with actual path degradation. When used as a tool in path network planning, it can aid in the selection of low-maintenance routes and also help in planning maintenance budgets.  相似文献   
54.
国际贸易中的环境要项   总被引:1,自引:0,他引:1  
环境要素在流动性决定了国际间环境与贸易的紧密联系。随着世界快速的经济一体化,将环境要项纳入国际贸易的规范、条款已势在必行。文章分析了环境成本内在化和ISO14000的实质,它们的内在联系及在国际贸易中的作用和影响,提出了将ISO14000作为实施环境成本内在化的参照规则的合理、可行性。  相似文献   
55.
OBJECTIVES: This work assesses the contribution to climate change resulting from emissions of the group of halogenated greenhouse gases. METHODS: A bottom-up emission model covering 22 technological sectors in four major regions is described. Emission estimates for 1996 and projection for 2010 and 2020 are presented. The costs for deep cuts into projected emission levels are calculated. RESULTS: The substances covered by this study have contributed emissions of 1100 +/- 800 MT CO2 equivalents per year in 1996. In terms of their relative contribution to emissions of CO2 equivalents, this corresponds to 3 +/- 2% of global emissions of all anthropogenic greenhouse gases. The wide range of uncertainty is due to the poorly quantified net global warming potential of the ozone depleting substances, which have an indirect cooling effect on climate through the destruction of stratospheric ozone. For annual emissions of HFCs, PFCs and SF6 (which are regulated under the Kyoto Protocol and for which global warming potentials are well defined), the relative contribution is projected to increase to 2% (600 MT CO2 eq.) of global greenhouse gas emissions by 2010. This trend is expected to continue, emissions are projected to grow to a contribution of roughly 3% (870 MT CO2 eq.) in 2020 compared to 0.9% (300 MT CO2 eq.) in 1996. For HFCs, PFCs and SF6, this study identifies global emission reduction potentials of 260 MT CO2 eq. per year in 2010 and 640 MT CO2 eq. per year in 2020 at below US$ 50 per ton. These values correspond to roughly 40% and 75% of projected emissions in 2010 and 2020, respectively.  相似文献   
56.
Adjustment costs from environmental change   总被引:4,自引:0,他引:4  
The paper is concerned with the case whereby the distribution of a firm's productivity shocks changes without the knowledge of the firm. Over time the firm learns about the nature and extent of the change in the distribution of the shock and adjusts, incurring adjustment costs in the process. The long-run loss in profits (±) due to the shift in the distribution we term the equilibrium response. The transitory loss in profits, incurred while the firm is learning about the distribution shift, is termed the adjustment cost. The theory is then applied to the problem of measuring adjustment costs in the face of imperfectly observed climate change in agriculture. The empirical part of the paper involves estimating a restricted profit function for agricultural land in a five-state region of the Midwest US as a function of prices, land characteristics, actual weather realizations and expected weather. We then simulate the effect of an unobserved climate shock, where learning about the climate shock is by observing the weather and updating prior knowledge using Bayes Rule. We find adjustment costs to climate change are 1.4% of annual land rents.  相似文献   
57.
交通噪声污染经济损失估算方法比较研究   总被引:3,自引:0,他引:3  
陈婷  陆雍森 《交通环保》2004,25(5):15-17,28
目前闷内外对于噪声污染经济损失的研究还相当有限,且采用的方法也存在很大的差别。运用环境经济学的观点和方法,提出了估算噪声污染损失的3种常用方法;损害费用法、意愿型调查评估法和防护费用法,并对其进行了比较研究。  相似文献   
58.
Objective: This study aimed to investigate the social and hospital costs of patients treated at a public hospital who were motorcycle crash victims.

Method: This prospective study was on 68 motorcycle riders (drivers or passengers), who were followed up from hospital admission to 6 months after the crash. A questionnaire covering quantitative and qualitative questions was administered.

Results: Motorcycle crash victims were responsible for 12% of the institution's hospital admissions; 54.4% were young (18–28 years of age); 92.6% were the drivers; 91.2% were male; and 50% used their motorcycles as daily means of transportation. Six months afterward, 94.1% needed help from someone; 83.8% had changed their family dynamics; and 73.5% had not returned to their professional activities. Among the injuries, 94.7% had some type of fracture, of which 53.5% were exposed fractures; 35.3% presented temporary sequelae; and 32.4% presented permanent sequelae. They used the surgical center 2.53 times on average, with a mean hospital stay of 18 days. The per capita hospital cost of these victims’ treatment was US$17,481.50.

Conclusion: The social and hospital costs were high, relative to the characteristics of a public institution. Temporary or permanent disability caused changes to family dynamics, as shown by the high numbers of patients who were still away from their professional activities more than 6 months afterward.  相似文献   

59.
通过分析国内外垃圾焚烧发电厂烟气净化系统的现状,基于燃煤电站和垃圾焚烧发电厂烟气物性之间的相似性及燃煤电站超低排放系统的先进性,提出了分别以循环流化床法脱硫和高效协同型湿法脱硫技术为核心的垃圾焚烧烟气超低排放改造可行技术路线,并分析了2种技术路线的初投资和运行成本.结果表明:2种技术路线的初投资相当,约为1.37万元/t,但以湿法脱硫为核心的技术运行费用较高,日运行成本约为16.46元/t;采用环保电价补贴政策时,2种烟气超低排放技术路线超过政策发电量部分的发电收入分别可以在3a和7a内弥补超低排放改造及运行带来的资金支出.  相似文献   
60.
目前,煤矿建设仍然存在绿色生态投入动力不足的问题。本文首先指出了绿色生态矿山建设的现状,并运用外部性理论分析煤矿绿色生态投入不足的经济机理;最后,基于外部成本内化深入分析了外部影响因素对绿色生态矿山建设的影响机理。  相似文献   
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