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41.
在国家相关政策的支持引导下,采用政府和社会资本合作(PPP)模式实施的水污染防治项目逐渐增多。合理的投资回报是社会资本参与PPP项目的关键所在。本文通过对水污染防治项目特点、不同付费方式及适用条件进行分析,对投资回报的内在机理进行了分析,提出水污染防治PPP项目投资回报机制设计原则,包括应符合市场配置特点,充分考虑项目风险影响,确保社会资本"盈利但不暴利"、以政府财政承受能力为底线、不以保底承诺、固定回报变相融资。在此基础上,从投资回报是社会资本方服务绩效的对价、合理设计保底需求和超额收益分享机制、合理设计服务价格及调整机制、合理拓宽可行性缺口补助投资回报方式等方面对投资回报机制要点进行了探讨,以期为同类项目的实施提供参考。  相似文献   
42.
ABSTRACT: As population growth occurs in regions of the eastern United States that do not have abundant water supplies, new transbasin diversions may be required. Such diversions are exceptionally politically divisive and are at the core of most of the interstate water conflicts that presently exist in the eastern states. This study examines alternative means by which these conflicts might be resolved. The strengths and weaknesses of these alternatives are examined. The study concludes that the federal-interstate compact should be the preferred alternative by which interstate water conflicts in the eastern United States are resolved.  相似文献   
43.
流域生态补偿支付方式研究   总被引:4,自引:0,他引:4  
通过对国内外流域生态补偿支付方式的系统研究,指出作为公共支付的重要补充,市场贸易支付在国外已经比较完善,但在中国,其所占份额少,尤其是开放式贸易支付方式尚未起步。建立和完善相关交易标准、法律和规章平台,充分发挥市场贸易支付的作用,对于改善流域生态补偿效果具有重要意义。同时,本文还对流域生态补偿支付方式的选择进行了探讨。  相似文献   
44.
Traditional olive orchards account for a large share of the area under olives in the EU, particularly in marginal areas, like those analysed in the OLIVERO project. In general, traditional olive growing can be described as a low-intensity production system, associated with old (sometimes very old) trees, grown at a low density, giving small yields and receiving low inputs of labour and materials. Though such systems are environmentally sustainable, their economic viability has become an issue, since EU policies favour more intensive and competitive systems. Orchards that have not been intensified seem to be threatened by the recent reform of the EU olive and olive oil policy, as income support has been decoupled from production. The main purpose of this paper is to identify the present constraints to traditional olive growing, and to recommend some private and public interventions to prevent its abandonment. During the OLIVERO project, traditional olive production systems were identified and described in five target areas (Trás-os-Montes-Portugal, Cordoba and Granada/Jaen-Spain, Basilicata/Salerno-Italy, and West Crete-Greece). The causes and consequences of abandonment are discussed, based on the analysis of the costs and returns, which revealed that these systems are barely economically sustainable. Their viability is only assured if reduced opportunity costs for family labour are accepted, and the olive growing is part-time. Based on these results, recommendations are made to prevent the abandonment of traditional olive growing and to preserve its environmental benefits.  相似文献   
45.
文章对重点污染行业和一般行业的定价方案、排污权时限、定价方式等进行系统研究。采用环境容量资源恢复成本定价法,以社会平均污染治理成本为基础,考虑排污权时限及贴现率方式,来估算排污权初始分配价格的参考值,同时调研重点污染和一般行业的二氧化硫、氮氧化物、COD和氨氮的消减成本,以重点污染和一般行业污染物消减成本为基础,再考虑温州的经济状况及环境质量状况确定估算排污权初始分配价格,详细评估温州排污权交易初始价格标准,并提出了温州市初始排污权有偿使用费、政府储备排污权有偿使用费征收标准。  相似文献   
46.
中国排污权有偿使用定价及政策影响研究   总被引:1,自引:2,他引:1       下载免费PDF全文
排放配额的价格是排污权有偿使用政策的关键要素之一。本研究从分析排污权有偿使用政策的内涵出发,厘清有偿使用政策与已有排污收费政策的区别,排污收费是企业为污染物排放造成对环境损害而支付的补偿,而有偿使用费是企业为污染物排放占用环境容量资源支付的稀缺租金。本研究同时考虑了现行排污收费政策和总量控制政策的影响,基于最优化控制理论建立了COD和NH_3-N两种水污染物为独立变量的价格模型,并对有偿使用政策执行后可能带来的影响进行了模拟预测。  相似文献   
47.
Southeast Asia possesses the highest rates of tropical deforestation globally and exceptional levels of species richness and endemism. Many countries in the region are also recognized for their food insecurity and poverty, making the reconciliation of agricultural production and forest conservation a particular priority. This reconciliation requires recognition of the trade‐offs between competing land‐use values and the subsequent incorporation of this information into policy making. To date, such reconciliation has been relatively unsuccessful across much of Southeast Asia. We propose an ecosystem services (ES) value‐internalization framework that identifies the key challenges to such reconciliation. These challenges include lack of accessible ES valuation techniques; limited knowledge of the links between forests, food security, and human well‐being; weak demand and political will for the integration of ES in economic activities and environmental regulation; a disconnect between decision makers and ES valuation; and lack of transparent discussion platforms where stakeholders can work toward consensus on negotiated land‐use management decisions. Key research priorities to overcome these challenges are developing easy‐to‐use ES valuation techniques; quantifying links between forests and well‐being that go beyond economic values; understanding factors that prevent the incorporation of ES into markets, regulations, and environmental certification schemes; understanding how to integrate ES valuation into policy making processes, and determining how to reduce corruption and power plays in land‐use planning processes.  相似文献   
48.
Auctions have been proposed as alternatives to payments for environmental services when spatial interactions and costs are better known to landowners than to the conservation agency (asymmetric information). Recently, an auction scheme was proposed that delivers optimal conservation in the sense that social welfare is maximized. I examined the social welfare and the budget efficiency delivered by this scheme, where social welfare represents the difference between the monetized ecological benefit and the conservation cost incurred to the landowners and budget efficiency is defined as maximizing the ecological benefit for a given conservation budget. For the analysis, I considered a stylized landscape with land patches that can be used for agriculture or conservation. The ecological benefit was measured by an objective function that increases with increasing number and spatial aggregation of conserved land patches. I compared the social welfare and the budget efficiency of the auction scheme with an agglomeration payment, a policy scheme that considers spatial interactions and that was proposed recently. The auction delivered a higher level of social welfare than the agglomeration payment. However, the agglomeration payment was more efficient budgetarily than the auction, so the comparative performances of the 2 schemes depended on the chosen policy criterion–social welfare or budget efficiency. Both policy criteria are relevant for conservation. Which one should be chosen depends on the problem at hand, for example, whether social preferences should be taken into account in the decision of how much money to invest in conservation or whether the available conservation budget is strictly limited.  相似文献   
49.
阐述了电子支付系统的概念、特点,并论述了电子支付系统的安全性要求.  相似文献   
50.
Abstract: Ecosystem services are being protected and restored worldwide through payments for ecosystem services in which participants are paid to alter their land‐management approaches to benefit the environment. The efficiency of such investments depends on the design of the payment scheme. Land features have been used to measure the environmental benefits of and amount of payment for land enrollment in payment for ecosystem services schemes. Household characteristics of program participants, however, may also be important in the targeting of land for enrollment. We used the characteristics of households participating in China's Grain‐to‐Green program, and features of enrolled land to examine the targeting of land enrollment in that program in Wolong Nature Reserve. We compared levels of environmental benefits that can be obtained through cost‐effective targeting of land enrollment for different types of benefits under different payment schemes. The efficiency of investments in a discriminative payment scheme (payments differ according to opportunity costs, i.e., landholders’ costs of forgoing alternative uses of land) was substantially higher than in a flat payment scheme (same price paid to all participants). Both optimal targeting and suboptimal targeting of land enrollment for environmental benefits achieved substantially more environmental benefits than random selection of land for enrollment. Our results suggest that cost‐effective targeting of land through the use of discriminative conservation payments can substantially improve the efficiency of investments in the Grain‐to‐Green program and other payment for ecosystem services programs.  相似文献   
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