虚拟水贸易的可计算非线性动态投入产出分析模型

虚拟水是水资源需求管理的创新领域。投入产出法是研究虚拟水的重要方法,但既有研究多以线性静态投入产出模型为主,存在较强的比例性假设,在解释现实经济活动中的虚拟水贸易时存在一定缺陷和不足。为更加贴近现实状况,本文利用可计算一般均衡(CGE)思想,设计了一种新的虚拟水测算思路,对传统的线性静态投入产出模型进行了非线性和动态化的拓展,旨在对区域经济系统中的虚拟水贸易进行更加科学合理的计算和考察。首先,参照国家统计机构常用的42产业部门划分方式,根据一般均衡理论,围绕区域经济系统的生产模块、价格模块和供需平衡模块三个部分,定义有关变量和参数,对区域经济系统非线性动态投入产出模型进行了详细的方程列写。在此基础上,将虚拟水流动的因素与一般形式的非线性动态投入产出模型进行嵌套,采用"母表"(价值型流量表)和"子表"(水资源流量表)相结合的形式,给出了一种全新的区域水资源投入产出表的设计思路与编制方法,将可计算非线性动态产出模型从一般形式扩展至水资源领域,构建了区域经济系统中虚拟水贸易的可计算非线性动态投入产出分析框架。分析同时指出,通过对该模型进行求解,可以推导和计算平衡增长路径和最优增长路径下的区域经济系统产出结构和用水结构,并可结合虚拟水贸易对区域经济的作用机理,分析最优增长路径下实施虚拟水贸易对区域经济增长的贡献。

Computable nonlinear dynamic input-output analysis model of virtual water trade

The virtual water theory is a creative field in the management of water resource demands.The input-output model is one of the most important methods for the study of virtual water, but most current researches have been linear and static, with strong proportionality assumption, and have had some defects and deficiency in the explanation of virtual water trade in the realistic economic activities.In order to be closer to the reality, this paper put forward a new calculation method for virtual water based on the idea of computable general equilibrium (CGE), which added nonlinear and dynamism to the traditional input-output model to achieve more scientific and reasonable calculation and investigation of the virtual water trade in the regional economic system.First, according to the 42 industrial sectors commonly used by the national statistical agencies and the general equilibrium theory, as well as based on the production module, price module and supply and demand balance module of regional economic system, this paper defined the related variables and parameters, and wrote the equation describing the nonlinear dynamic input-output relation of regional economic system.Then, nesting the factors of the virtual water flow into the regular nonlinear and dynamic input-output model, and combining the economic value flow meter and water flow meter, it designed a new method for the compilation of regional water resources input and output table, so that the nonlinear dynamic output model could be calculated from the general form to the field of water resources, and the nonlinear dynamic input-output analysis framework of the virtual water trade in the regional economic system was established.Through the analysis above, it also showed that by solving this model, the output structure and water structure of the regional economic system under the balanced growth path and the optimal growth path could be deduced and calculated, and the contribution of the virtual water trade to the regional economic growth in the optimal growth path could also be analyzed according to the mechanism of the effect of virtual water trade on regional economy.