水资源短缺地区河道生态基流的价值与保障补偿机制研究

In order to maintain the river's primary function of ecological environment, river channel should keep certain basic flow perennially, especially in dry season, which is called the ecological basic flow. In water shortage area, the critical period of channel's ecological basic flow guarantee is in dry season. In this period the conflict between river's guarantee of ecological basic flow and local production water supply of industry and agriculture is very sharp. Although the significance of ecological basic flow is gradually realized by people, ecological basic flow is still often at a disadvantaged position compared to production water supply, because its value is difficult to quantification and monetization, which caused it can not be effectively guaranteed. So as to solve the problem scientifically and reasonably, the main research scopes of this project are as follows: 1) on the basis of analysing the function of ecological basic flow, the value computational method of ecological basic flow will be studied, and which can be applied to reveal the time and spatial distuibution characteristics of the ecological basic flow's value; 2) the cost computational method of ecological basic flow guarantee will be established, which can acquire the losses and costs for all affected sectors and determine the reasonable level of ecological basic flow guarantee; 3) the compensation standard computational method of ecological basic flow guarantee will be developed, and the compensation methods will be studied, which is help to the construction of the compensation mechanism of ecological basic flow guarantee in the water shortage area; and 4) finally, the case study of the Guanzhong reach of Weihe River in Shaanxi will be carried out. The results of this project not only provide theoretical support and scientific basis for the decision-making of ecological basic flow guarantee as well as scientific management of limited water resources in dry season for water shortage region, but also have practical significance to river's health.

为了维持河流的基本生态环境功能，河道中常年、特别是枯水期都应保持一定的基础流量，即生态基流。在水资源短缺地区，河道生态基流保障的关键期为枯水期，这时河道生态基流保障与当地生产用水之间的矛盾非常尖锐。虽然人们逐步认识到了生态基流的重要性，但由于生态基流的价值比较难以定量化和货币化导致其往往处于劣势地位，造成生态基流难于有效保障。因此，本项目拟在分析河道生态基流功能的基础上，主要研究生态基流价值的计算方法，揭示生态基流价值的时空变化特征；建立生态基流保障代价的分析计算方法，推求受影响各方的损失和代价，确定河道生态基流的合理保障水平；研究生态基流保障补偿标准的计算方法，探讨补偿途径，从而构建水资源短缺地区生态基流的保障补偿机制。最后，进行渭河干流关中段的实例应用研究。这些研究不仅可以为缺水地区生态基流的保障决策与枯水期有限水资源的科学管理提供理论支撑与科学依据，而且对河流健康的实现具有现实意义。

近年来，我国西北水资源短缺地区部分河道出现了断流、萎缩等现象，主要是由于生产用水和生态用水之间协调不当引起的。为了维持河流的基本生态环境功能，河道中常年、特别是枯水期都应保持一定的基础流量，即河道生态基流。目前关于河道生态基流价值的定量化与货币化研究较少，河道生态基流保障对其他用水部门造成的经济损失量和补偿机制也缺乏研究，满足不了河道生态基流合理保障的需要。为此，本项目以西北水资源短缺地区为背景，对这些问题开展了比较系统的研究，提出了河道生态基流价值的定量化方法、生态基流保障的损失量计算模型、初步构建了河道生态基流保障的补偿机制，对水资源短缺地区河道生态基流的合理保障具有重要意义。本项目取得的研究成果主要有：（1）根据河道生态基流的定义和内涵，参照生态系统服务功能，对水资源短缺地区河道生态基流的功能进行了识别和辨析；提出了水资源短缺地区河道生态基流价值的3种计算方法，包括分项价值综合法，模糊数学法以及能值分析法；构建了研究河道生态基流价值时空变化的方法，如能值分析法和变异系数法。（2）借助生产函数法和效益分摊系数法建立了水资源短缺地区生产用水部门（工业、农业）的用水产生的经济效益的量化计算模型；通过分析河道生态基流保障的主要措施与影响因素，构建了河道生态基流保障的经济损失量计算模型。（3）在河道生态基流的价值与基流保障损失量研究的基础上，建立了水资源短缺地区河道生态基流合理保障水平的分析计算方法与模型。（4）考虑水资源短缺地区生产用水和生态用水之间的复杂性与矛盾关系，初步建立了水资源短缺地区的河道生态基流保障的补偿机制。（5）以水资源短缺地区的典型河段——渭河干流关中段为对象，开展了实例研究，综合应用本项目提出的理论方法和计算模型对该河段进行了定量分析计算，初步建立了生态基流保障的补偿机制。本项目的研究成果可为水资源短缺地区河道生态基流长效保障机制的建立提供科学依据。