循环经济条件下水定价与社会福利的数理研究

A Mathematic Study of Water Pricing and Social Welfare in the Background of Water Reuse and Recycling

本文采用福利经济学的分析框架和数理模型方法,从当今水资源循环经济日益重要的背景特点和水定价多重目标均衡的角度出发,把供水总量约束和生态恢复率因素引入福利最大化函数,研究基于生活、生产和生态用水等水的不同用途的最优定价机制。模型分析表明:存在使水资源与水产品在不同用途间实现合理配置的最优水价;水价尤其是水价的提高有利于促进节水目标的实现;真实水价提高时水的循环利用率提高,而恢复率却会下降,但生态用水量的变化方向不能够确定。

This study establishes a three different uses of water for living, welfare optimization pricing model based on production and ecological purposes, in the background of water reuse and recycling, with the constraint of total water supply and a factor of ＂ecological recovery rate＂ . Modeling result shows, there exists an optimized water price that could realize the reasonable allocation of water between different uses; water price, especially price rising, may help to reduce water use; when real water price rises, the reuse and recycling rate of water increases, but the ＂ecological recovery rate＂ drops. The results remind us that simply raising water price may not realize the maximization of total human wellbeing; other measures should be taken to guarantee that water discharged have ecological functions.