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191.
ABSTRACT: There are many factors, other than economic efficiency, which must be considered in judging the merits of proposed investments in the inland navigation system. No satisfactory formula exists for deciding the net worth of public investments in water resources projects. Such a measure would not be accepted because these investments can serve conflicting goals. Political, rather than technical, judgments are required to resolve these goal conflicts.  相似文献   
192.
ABSTRACT: A mathematical programming model is proposed to determine economically efficient urban water resource allocation and pricing policy by maximizing the sum of the consumer and producer surplus. The optimization of this nonlinear problem is accomplished by the use of linear programming algorithm. The feasibility of using recycled water for municipal purposes is examined in a planning context. The impact of higher water quality discharge standards on pricing and allocation of water is analyzed and the attractiveness of water reuse option is demonstrated.  相似文献   
193.
ABSTRACT: Participation in water-based recreation activities does not arise in random fashion nor simply as a result of having a water resource immediately available. Neither do individuals and groups engage in the same activities or a specific activity in the same way. The purpose of the present paper is to describe an alternative framework whereby differences among recreation users can be identified. Prior to this time, research directed toward understanding participation patterns at a recreational site have emphasized the activities while ignoring the human behavior factors which determine how participation arises. People consider recreation sites to be leisure settings in which the definition of such places has a broader socio-cultural meaning than that the site was designed. These definitions are reflected within the context of the social group and can be observed in the subsequent orientation to leisure and play. When activities are considered in the context of a human group, differences in participation patterns can be discovered.  相似文献   
194.
Abstract:  The traditional environmental Kuznets curve (EKC) hypothesis postulates that environmental degradation follows an inverted U-shaped relationship with gross domestic product (GDP) per capita. We tested the EKC hypothesis with bird populations in 5 different habitats as environmental quality indicators. Because birds are considered environmental goods, for them the EKC hypothesis would instead be associated with a U-shaped relationship between bird populations and GDP per capita. In keeping with the literature, we included other variables in the analysis—namely, human population density and time index variables (the latter variable captured the impact of persistent and exogenous climate and/or policy changes on bird populations over time). Using data from 9 Canadian provinces gathered over 37 years, we used a generalized least-squares regression for each bird habitat type, which accounted for the panel structure of the data, the cross-sectional dependence across provinces in the residuals, heteroskedasticity, and fixed- or random-effect specifications of the models. We found evidence that supports the EKC hypothesis for 3 of the 5 bird population habitat types. In addition, the relationship between human population density and the different bird populations varied, which emphasizes the complex nature of the impact that human populations have on the environment. The relationship between the time-index variable and the different bird populations also varied, which indicates there are other persistent and significant influences on bird populations over time. Overall our EKC results were consistent with those found for threatened bird species, indicating that economic prosperity does indeed act to benefit some bird populations.  相似文献   
195.
Abstract: The conflict between economic growth and biodiversity conservation is understood in portions of academia and sometimes acknowledged in political circles. Nevertheless, there is not a unified response. In political and policy circles, the environmental Kuznets curve (EKC) is posited to solve the conflict between economic growth and environmental protection. In academia, however, the EKC has been deemed fallacious in macroeconomic scenarios and largely irrelevant to biodiversity. A more compelling response to the conflict is that it may be resolved with technological progress. Herein I review the conflict between economic growth and biodiversity conservation in the absence of technological progress, explore the prospects for technological progress to reconcile that conflict, and provide linguistic suggestions for describing the relationships among economic growth, technological progress, and biodiversity conservation. The conflict between economic growth and biodiversity conservation is based on the first two laws of thermodynamics and principles of ecology such as trophic levels and competitive exclusion. In this biophysical context, the human economy grows at the competitive exclusion of nonhuman species in the aggregate. Reconciling the conflict via technological progress has not occurred and is infeasible because of the tight linkage between technological progress and economic growth at current levels of technology. Surplus production in existing economic sectors is required for conducting the research and development necessary for bringing new technologies to market. Technological regimes also reflect macroeconomic goals, and if the goal is economic growth, reconciliatory technologies are less likely to be developed. As the economy grows, the loss of biodiversity may be partly mitigated with end‐use innovation that increases technical efficiency, but this type of technological progress requires policies that are unlikely if the conflict between economic growth and biodiversity conservation (and other aspects of environmental protection) is not acknowledged.  相似文献   
196.
林业政策在对森林资源的培育、保护和利用方面起相当大的作用.在市场机制作用的框架下林业政策的作用更多的是通过影响市场机制传递的产品和生产要素的价格信号,进而影响生产经营主体的收益成本预期及其决策行为,最终影响到对森林资源的培育、保护和利用的效果,因此分析和认清林业政策对林业发展的作用机制和影响效果有重要的意义.本文基于市场机制.以林业经济福利为目标,把森林资源培育的第一产业环节和以森林资源为原料的第二产业发展结合一起作为完整的产业链,构建一个林业的政策模拟模型.利用该模型,对木材价格、林业税费、信贷利率和采伐限额等林业经济政策的影响进行了定量分析,着重比较了林业产权制度改革前后政策变化所产生的效应,以及所具有的激励效果,从而认识林业政策的变动和调整如何影响政策目标,为政策的制定和对合理政策进行选择提供参考的依据.  相似文献   
197.
This paper examines whether foreign aid, together with other economic, social and environmental factors, contributes to sustainable development. It starts with an illustrative theoretical growth model where foreign aid promotes sustainable development by protecting the environment. Using factor analysis and newly developed estimation methods for a dynamic panel data model with endogenous regressors, the empirical section of the paper finds evidence that foreign aid has had a significantly positive influence on sustainable development in aid recipient countries. This effect is very likely to go through channels related to growth and resources as well as a technology channel with respect to energy intensity. This research has important implications for a post‐2015 development framework on international collective action with regard to a sustainable future.  相似文献   
198.
Recreational horseback riding is an important, but less studied, component of human interaction with the natural environment and often occurs alongside other outdoor recreational activities. Using choice experiment data collected from a survey conducted in Kentucky, this study assesses rider preferences and economic values associated with various equestrian trail attributes for daylong horseback riding trips in rural trail systems. Results indicate that while individuals have different opinions, trail attributes such as length of trail, scenic views, and travel distance from home all have significant economic implications. In addition, riders prefer trails that are restricted for horse riding only. Willingness to pay estimates of all attributes increase substantially when the travel cost to reach the trail is also considered. Policy implications on maintaining current and creating new trails in a multi-user setting are given, such as the opportunities for separating horseback riders from other users while still providing other beneficial attributes like options for longer trails and scenic views to all groups.  相似文献   
199.
污染排放对经济发展的负面影响研究   总被引:1,自引:1,他引:0       下载免费PDF全文
以1998—2009 年各地区的数据为样本,利用联立方程模型检验污染排放对经济发展的负面影响,以及宏观经济结构对这种影响的调节作用.研究发现,经济发展与污染排放之间存在相互影响的关系,经济结构与污染排放之间也存在相互影响的关系.当期经济发展水平的提高必然会引起污染排放的增加,但当期污染排放的增加会对今后经济发展产生滞后的负面效应.投资和出口对污染排放的负面影响存在调节作用,即投资比重越高,出口比重越低,当期经济增长引起的污染排放越少,污染排放的负面影响也越小.不过,消费比重对污染排放负面影响不存在调节作用.  相似文献   
200.
赤潮灾害经济损失评估技术方法   总被引:3,自引:0,他引:3  
为有效应对赤潮灾害防灾减灾、灾后救援及管理的需求,在综合分析前人提出的赤潮灾害损失评估技术方法的基础上,参考赤潮灾害对受灾体的危害特点,结合实际工作的需求及在实际中可获取的业务数据,提出了赤潮灾害经济损失评估指标体系;根据灾害经济学理论,借鉴其他自然灾害经济损失评估的先进思想,采用市场价格法,分别建立了包括海水养殖业经济损失、滨海旅游业经济损失、赤潮灾害业务与应急监测费用和赤潮灾害处置费用的赤潮灾害经济损失评估模型;最后,提出了赤潮灾害损失评估的技术流程。  相似文献   
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