经济学视角下的流域生态补偿制度——基于一个污染赔偿的算例

The watershed eco-compensation system from the perspective of economics:the cases of pollution compensation

近年来,随着流域水污染问题日益严重,流域上下游之间的利益冲突日趋明显,流域生态补偿成为协调流域上下游利益冲突的重要途径。虽然我国一些地区已经开展了流域生态补偿的实践,并取得了一定成效,但在具体执行中还存在许多问题。通过分析不同制度安排下流域上下游利益相关者的福利变化,来说明制度的重要作用。在介绍有关制度的重要概念后,通过比较"囚徒困境"和"囚徒梦想"两个博弈案例,指出了制度安排对效率的重要影响,即效率和公平的是由现有制度安排决定的,在每一种制度安排下,效率和公平的含义会有所不同。基于一个流域污染赔偿的算例,分析了四种制度安排下的效率差异。在这个例子中,甲代表上游的排放污水的企业,乙代表下游受害的居民。在第一种制度安排下,甲不用考虑对乙造成的损失,双方的总收益实现了最大化,但大多数人会认为这种制度安排对乙不公平。在后三种"更公平"的制度安排下,存在着对乙的利益进行补偿的不同方案,且在第三种制度安排下,双方的总收益同样达到了最大化,只有在对甲进行强制的制度安排下(即强制要求甲安装污水处理设施),双方的总收益均少于其它三种制度。对案例的分析表明:(1)通过设计合理的制度,公平和效率可以"兼得";(2)如果利益相关者拥有影响制度安排的机会,将能够促进社会公平。研究为决策者提供一个分析框架,对缓解目前流域生态补偿中上下游的利益冲突具有重要的意义。

The growing problems in water pollution at a watershed scale have caused more and more conflicts between upstream and downstream regions, making ecological compensation a vital approach to balance the interests of all stakeholders within the watershed concemed. Presently, ecological compensation has been practiced in some areas and gained certain progress, but problems have been revealed during the practice as well. In this paper we tend to illuminate the importance of system arrangement by analyzing the changes in benefits of stakeholders in upstream and downstream under various systems. We introduce the basic concepts involved in explaining the connotation of the systems. We then compare two cases （Prisoner＇s Dilemma and Prisoner＇s Dream） to better illustrate how efficiency is influenced by the systems. Based on the case studies, we point out that efficiency and equity are determined by the current systems, and the meaning of efficiency and equity might be different in each system. We also analyze the role of the systems in promoting ＂efficiencyand equity＂ which is narrowly defined in this paper of watershed ecological compensation based on a hypothetical example. In this example, A represents the factory upstream while B represents the resident downstream being polluted by the waste water from factory. Besides, There are four types of system in this example ： In the first system, A does not have to take into account the loss of B, and their total income has realized the maximization, but the majority of people will think this system is unfair to B ; In the last three ＂fairer＂ systems, each has a compensation plan for B, the income of both sides also has reached the maximization in the third system as the same as it in the first system, while the total income in the fourth is the lowest of all in which A is required to install sewage treatment facilities. We conclude that （ 1 ） it will probably gain both efficiency and equity by designing a reasonable system and （2） giving stakeholders more power to affect institutional design will promote the social equity. Our results could provide support to building an analytical framework for decision makers and has significant values for alleviating the conflict of interest between upstream and downstream stakeholders in the practice of watershed eco-compensation.