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211.
本文从可持续发展的思想出发 ,分别运用西方经济学和环境经济学方法对唐山开滦煤矿的复垦农业模式的特征及其可持续性进行了分析与比较 ,并据此为该区域的土地复垦提出了一种可行的方案建议。  相似文献   
212.
针对高职院校经济类专业校内实训基地建设中存在的基地建设欠缺、设施建设不完善和规划不合理等问题,经济类专业校内实训基地建设应该采取寻求社会支持、构建新型实践教学体系等措施,以提高整体实践教学水平,达到高职院校经济类专业能够重点培养学生职业能力的效果。  相似文献   
213.
    
In recent years valuations of cultural goods and services have been undertaken using the contingent valuation method, because of its flexibility and the advantages it affords over other methods of valuing non-market goods. Yet, in contingent valuation literature few studies have addressed the reliability of the outcomes. This is the goal of the current paper, which presents the results of anapplication of the contingent valuation method to a new museum of contemporary art (Museo Patio Herreriano de Arte Contemporáneo [Spanish Contemporary Art Museum] in Valladolid, Spain). The method was applied at two different times: prior to its opening and after some years. We thus aim to contrast the evolution of preferences and willingness to pay (WTP) estimates at different points in time using bootstrap techniques. Estimations were performed using non-parametric methods and the outcomes reflect stability for valuations made by visitors to the museum but not for the valuations given by residents of Valladolid.  相似文献   
214.
    
Over the course of Australia's Millennium Drought, urban water managers gained more appreciation of householders' willingness and capacities to respond to water shortages and restrictions, including by installing rainwater tanks (RWTs) for watering gardens. How urban water managers regard tanks and tank users gives insight into their understandings of social sustainability, as found in interviews conducted in 2006 and 2010. These also revealed a growing distance between policymakers and water providers pursuing a broader approach to sustainability in their communities. The RWT is considered here as a limit case for paradigms of urban water management: it challenges conventional distinctions (such as provider/consumer) and heralds a new hydropolitics. These challenges are discussed as seven kinds of trouble with tanks: (1) incompatibility with the management model and vision of modernity enshrined in the ideal of centralised provision in control of accredited water experts; (2) anxieties about control and risk aroused by these private on-site facilities and their non-expert users; (3) equivocation over their environmental effects, normally assessed in hydrological terms that downplay the benefits of green streetscapes; (4) inexplicability of their popularity within dominant economically rationalist models of customers; (5) educational effects that exceed rationalist, individualist models of learning and require more socially realistic, culturally intelligent and practice-oriented approaches; (6) generation of enthusiasms that are spurned as threats to rationality instead of harnessed to energise the sustainability journey and (7) community-building effects that are unthinkable within the neoliberal customer paradigm but graspable to water managers through lay concepts like “dinner table conversations”.  相似文献   
215.
ABSTRACT A mathematical programming model is structured to find the optimal time and capacity expansion path of desalination plants and storage tanks for a hypothetical community which depends on desalination as its sole, or major, water supply source. The objective is to determine the least costly combination of sues and times of installation (of both desalting plants and storage tanks) which can meet a rising water demand over a finite planning horizon. The optimality criterion used in the model is based on two major economic elements: the economies of scale inherent in such facilities and the time-value of money represented by the interest rate, the former favoring large capacities and the latter small capacities. The model is applied using three population growth patterns and two interest rates. The water demand components for every year in the planning period are computed using empirical formulas which are based on population and other basic data. The model is solved for each of the above cases with the aid of a computer program based on the method of feasible conjugate directions. The results clearly reflect the balance between the economies of scale and the time-value of money under every demand growth function.  相似文献   
216.
Stephenson, Kurt and Leonard Shabman, 2011. Rhetoric and Reality of Water Quality Trading and the Potential for Market‐Like Reform. Journal of the American Water Resources Association (JAWRA) 47(1):15‐28. DOI: 10.1111/j.1752‐1688.2010.00492.x Abstract: Many public interest groups, government agencies, and professional economists argue that current approaches to water quality trading are a cost‐effective, politically practical innovation for achieving water quality standards, in part by addressing one of the most difficult water quality improvement challenges – limiting the discharge from nonpoint sources. A critical analysis shows that these claims for current water quality trading programs are often unrealized. This rhetoric, without adherence to principles of market‐like reform, can undermine the support of regulated parties for meaningful water quality policy reform, contribute to missed opportunities to implement cost‐effective programs, and postpone successfully meeting the challenge of limiting nonpoint source discharges. A better understanding and application of market‐like principles can result in an improved design of trading as well as general water quality management programs.  相似文献   
217.
ABSTRACT: A model is developed for real-time operation of an irrigation reservoir with the objective of maximizing the value of multiple crop yields during a growing season. The model employs monthly additive and product forms of crop yield functions for dry matter and grain crops, respectively. The resulting nonlinear optimization model uses a log transform to reduce nonlinearities in the model. An application of the proposed model is compared to a common operating rule used in simulation models. The proposed model results were better in terms of net benefits from crop yields. The model uses GAMS (General Algebraic Modeling System) language. It requires an IBM-compatible microcomputer and is suitable for use by a reservoir manager.  相似文献   
218.
    
ABSTRACT: Preservation of the few remaining ecologically vital riparian areas in the southwestern United States is a significant policy concern. This article reports on two economic aspects of preserving a nationally renowned riparian birding area in Southern California. First, the article examines visitor willingness to pay (WTP) for habitat restoration and estimates an annual WTP of US $77 per visitor to preserve the habitat, about a half‐million dollars a year for estimated visitor numbers in 2000 and 2001. Second, it documents visitor expenditures in the local economy to be approximately three‐quarters of a million dollars per year. This direct visitor spending attributable to the riparian habitat generates around US $1.3 million in increased local business activity in this relatively remote rural area.  相似文献   
219.
High alpine peaks throughout the world are under increasing environmental pressure from hikers, trekkers, and climbers. Colorado's “Fourteeners”, peaks with summits above 14,000 feet are no exception. Most of these peaks have no entrance fees, and reach ecological and social carrying capacity on weekends. This paper illustrates how a series of dichotomous choice contingent valuation questions can be used to evaluate substitutability between different alpine peaks and quantify the price responsiveness to an entrance fee. Using this approach, we find that peak load pricing would decrease use of popular Fourteeners in Colorado by 22%. This reduction is due almost entirely to substitution, rather than income effects. There is also price inelastic demand, as 60% of the hikers find no substitution for their specific Fourteener at the varying cost increases posed in the survey. The no substitute group has a mean net benefit of $294 per hiker, per trip, considerably higher than visitor net benefits in most recreational use studies.  相似文献   
220.
    
ABSTRACT: This paper presents the results of cost effectiveness (CE) analysis of vegetative filter strips (VFS) and instream half‐logs as tools for recovering scores on a fish Index of Biotic Integrity (IBI) in the upper Wabash River watershed (UW) in Indiana. Three assumptions were made about recovery time for IBI scores (5,15, and 30 years) and social discount rates (1, 3, and 5 percent), which were tested for sensitivity of the estimated CE ratios. Effectiveness of VFS was estimated using fish IBIs and riparian forest cover from 49 first‐order to fifth‐order stream reaches. Half‐log structures had been installed for approximately two years in the UW prior to the study and provided a basis for estimates of cost and maintenance. Cost effectiveness ratios for VFS decreased from $387 to $277 per 100 m for a 1 percent increase in IBI scores from first‐to fifth‐order streams with 3 percent discount and 30‐year recovery. This cost weighted by proportion of stream orders was $360. The ratio decreased with decreasing time of recovery and discount rate. Based on installation costs and an assumption of equal recovery rates, half‐logs were two‐thirds to one‐half as cost‐effective as VFS. Half‐logs would be a cost‐effective supplement to VFS in low order streams if they can be proven to recover IBI scores faster than VFS do. This study provides baseline data and a framework for planning and determining the cost of stream restoration.  相似文献   
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