基于水足迹理论与LMDI模型的贵州省水资源利用评价

基于水足迹理论构建区域水资源利用评价指标体系，分析贵州省2000-2017年水足迹时间变化，并采用LMDI模型探讨人口、经济和技术等驱动因素对水足迹变化的影响程度。结果表明:贵州省总水足迹经历了先波动增长后减少再逐渐增加的过程；水资源自给率年均达到97%以上，对外依赖程度较低；水足迹经济效益值逐年增加明显，水足迹土地密度与总水足迹变化趋势一致，而万吨水足迹人口密度则与总水足迹变化趋势相反；水资源压力指数整体维持在40%以上，其中偏枯水年和枯水年水资源压力指数大于70%；人文驱动因素对水足迹变化的影响程度:经济效应＞技术效应＞人口效应，自然驱动因素中降水量是导致水足迹变化的主要因素。 

Evaluation of water resources utilization in Guizhou Province based on water footprint theory and LMDI model

Guizhou Province is located in southwest China with a total land area of about 176,000 km2, accounting for 1.8% of the China’s land area. Karst landforms are widely distributed in this region with a large area of peak-clusters and depressions, forming a unique karst ecosystem. This region has subtropical humid monsoon climate, featured by notable spatial and temporal differences of precipitation. As a typical karst region, it has water resource vulnerability, manifested by low water storage capacity, frequent seasonal drought, and the water environment is easily polluted and difficult to recover. In recent years, the engineering water shortage problem has been significantly improved with the comprehensive progress of large-scale water source project construction in Guizhou Province. In order to evaluate current situation of water resources utilization and the driving factors affecting water use in Guizhou Province, this work established a water resources utilization evaluation index system, based on the water footprint theory; and the analysis of temporal changes of the water footprints from 2000 to 2017 was carried out. The LMDI model was used to examine the impact extent of population, economic and technological driving factors on the changes of the water footprints. The results show that the total water footprint of Guizhou Province has experienced a process of growth from fluctuant to decreasing one and then gradually increase. The self-sufficiency rate of water resources is more than 97% per year, and the degree of external dependence is low; the economic benefit value of water footprints increases year by year. Water footprint land density is consistent with the trend of total water footprint. However, the population density of 10,000 tons of water footprint is inconsistent with the trend of total water footprint. The overall pressure index of water resources is maintained above 40%, of which the water stress index of semi-dry and dry years is greater than 70%. Based on the LMDI model, the impact degree of anthropogenic driving factors on the changes of water footprint, is in the order of economic effect>technical effect>population effects. Among them, economic effects account for 53.22% of the impact, while technical effects contribute 46.1% and population effects are only 0.68%. Precipitation as a main natural driving factor is also leading the changes in water footprint.