中国主要农产品虚拟水变化驱动因素及地区差异分析

Analysis of driving factors and regional differences of major agricultural products' virtual water change in China

中国主要农产品的虚拟水总量随着时间不断变化,研究这种变化趋势的驱动因素,有利于节约农业用水,将有限的水资源用于其他领域,促进整个国民经济的发展。基于改进的LMDI模型,将东部、中部、西部地区的2000—2013年的主要农产品虚拟水变化影响因素分解为用水强度效应、产值结构效应、经济效应和人口效应,探讨其对各地区农产品虚拟水量的影响差异。研究发现:经济效应和人口效应对虚拟水量的变化起到拉动作用,用水强度效应和产值结构效应对虚拟水量变化呈现较弱的抑制作用。4个效应对3个地区农产品虚拟水量变化的贡献趋势基本一致,从大到小排序均为经济效应、用水强度效应、产值结构效应、人口效应,仅在具体的贡献量上有所差别。用水强度和产值结构效应对3个地区虚拟水量的贡献随时间变化的趋势基本一致;相比东、中部地区而言,西部地区农产品虚拟水量受经济效应的拉动作用小;人口效应对东部地区的拉动作用最为显著。研究结论为我国缓解用水矛盾、解决水资源短缺危机提供决策依据。

Chinese main agricultural products' virtual water content is changing with time. Researching the driving factors of this trend is conducive to saving agricultural water,using limited water resources in other areas,promoting the development of the national economy.Based on the improved LMDI model,the main factors of agricultural products 2000—2013 years of virtual water changes in eastern,central and western regions is decomposed into water intensity effect,industrial structure effect,economic effect and population effect,to investigate the influence of virtual water of agricultural products regional differences. The results show that: first,the economic effects and population effects play a stimulating role in the virtual water quantity,and the water intensity effect and the output structure effect have a weak inhibitory effect on the virtual water quantity change. The four contribution trend effect on agricultural products in three areas of virtual water changes are basically the same,in descending order are economic effect,water intensity effect,value structure and population effect,only the difference in the amount of contribution. With the strength and structure effect of water on the output value of three regional virtual water changes with time in the same trend; compared to the eastern and central regions,the pulling effect of virtual water of agricultural products in western China under the economic effects of small population effect; the pulling effect of the eastern region is the most significant. The conclusion of the study can provide a basis for the mitigation of water consumption and the solution of the shortage of water resources in China.