基于供求关系和生产函数的灌区水量使用权交易模型

随着市场在资源配置中的作用日益重要,水权交易对优化水资源配置、提高用水效率、促进节水势在必行,现已成为我国最严格水资源管理制度试点建设的重要内容之一。本文运用水资源系统分析与经济学理论,建立了基于供求关系和生产函数的灌区水量使用权交易模型,该模型以交易双方各自收益最大化为目标,由C-D生产函数和供求关系确定水资源价值,以纳什均衡价格和供需水量为约束确定交易水量和交易收益。经湖北省高关水库灌区与应城市水量使用交易应用研究,结果表明:高关水库灌区随着节水深入,2013年现状、2020、2030规划水平年在50%平水年交易水量最大,分别为3 744.78万m3、4 743.51万m3、5 829.13万m3;75%、85%干旱年交易水量分别减少到1 225.28万m3~4 180.79万m3,213.65万m3~1 570.17万m3;90%特旱年则不具备交易条件。通过双方交易,可使应城市2013、2020、2030水平年50%平水年缺水情况明显缓解,75%和85%干旱年缺水率降低;还可提高高关水库灌区净收益201.73万元~7 0541.97万元,应城市净收益88.37万元~131 669.00万元。但要根本解决应城市干旱缺水问题,需要建立灌区节水量交易收益补偿投入机制,调动节水积极性,充分挖掘当地节水潜力。这对建立健全我国水权交易机制和最严格的水资源管理制度,提高水资源利用效益与效率,指导节水型社会建设,保障城乡供水安全,具有重要意义。

Water use right trading model of irrigation area based on supply-demand relation and production function

As market plays an increasingly important role in the allocation of resources, water right trading is imperative to optimize the allocation of water resources, improve the efficiency of water use and promote water saving,which has been an important part of the pilot construction of the most stringent water resources management system in China. In this paper, water resources system analysis and economic theory are used and water use right trading model of irrigation area is established on the base of supply-demand relation and the production function. In the model, the maximized transaction income of transactors is taken as the goal and the value of the respective water is determined by C-D production function and the supply-demand relation, and Nash equilibrium price and water quantity are bound to determine the transaction volume and transaction income. This model is applied to water use right trading between Gaoguan reservoir irrigation area and Yingcheng city in Hubei province. The results show that with the depth of water saving in Gaoguan reservoir irrigation area, transaction volume is maximal under 50% conditions of current year 2013, planning year 2020 and 2030, which are 37.447 million cubic metres, 47.44 million cubic metres, 58.29 million cubic metres, respectively; trading amount of dry year of 75% and 85% are reduced among 12.25 million cubic metres to 41.81 million cubic metres, and 2.14 million cubic metres to 15.70 million cubic metres,respectively;conditions of water use right trading are lacked in special drought year of 90%. Water use right trading can not only ease the level of water shortage significantly under 50% conditions of current year 2013, planning year 2020 and 2030 in Yingcheng city and make water shortage rate decreased, but also improve net benefit of Gaoguan reservoir irrigation area by 2.02 million yuan to 705.42 million yuan and improve net benefit of Yingcheng city by 0.88 million yuan to 1.32 billion yuan; but to fully solve the problem of water supply in Yingcheng city for drought year, it is necessary to establish water saving capacity trading income compensation investment mechanism of water saving in irrigation district, mobilize the enthusiasm of water conservation and fully tap the local water saving potential. It is of great significance to establish and improve the water right trading mechanism and the most stringent water management system, improve the utilization efficiency of water resources, guide water saving society construction in China,ensure the safety of urban and rural water supply.