粮食生产水足迹动态演变及分解效应

Dynamic Change and Decomposition Effects of Water Footprint in Grain Production

基于水足迹方法构建粮食生产水资源匹配指数,从用水总量、来源结构和粮水匹配关系三个方面分析粮食生产用水的动态演变特征,并采用LMDI模型将粮食生产用水变动分解为9类效应,研究结果表明:粮食生产水足迹变动经历小幅下降——快速回升——企稳上升三个阶段,粮水匹配度较差且矛盾趋于激化。从分解效应看,三产结构调整和节水技术进步是减少粮食生产用水的主要因素,但种植结构调整以及用水效率改善未发挥预期节水效果,粮水匹配关系恶化、水土资源贫乏及二者匹配度较差均不利于缓解农业用水压力。

Based on the water footprint method,this paper constructs the matching index of water resources and grain production,and analyses the dynamic evolution characteristics of water consumption for grain production from three aspects:total water consumption,source structure and matching relationship between grain production and water.Then use Logarithmic Mean Divisia Index method to decompose the change of water consumption in grain production into nine kinds of effects.The results show that:water footprint for grain production experienced three stages:a small decline,a rapid recovery and a steady rise.The grain production of food production is poorly matched and the contradictions tend to intensify.From the perspective of decomposition effect,the structural adjustment of the third-generation and the progress of water-saving technology are the main factors to reduce the water consumption in grain production;however,the relevant policies of water-saving in agriculture and the adjustment of planting structure have not brought the expected water-saving effect into full play;the matching relationship between grain and water is deteriorating,and there's a scarcity of water and soil resources and poor matching between them are not conducive to restraining the increase of water use.