Spatio-Temporal Study on Supply and Demand Matching of Ecosystem Water Yield Service -A Case Study of Wei River Basin

摘要

Wei River, as the largest tributary of the Yellow River, is facing an increasingly serious shortage of water resources. Therefore, it has a great significance to study the correlation between the supplydemand characteristics of water yield service and the spatial matching of supply and demand for the management and efficient allocation of water resources in the region. Based on the land use data, precipitation data, evaporation data, and water consumption data of the Wei River basin in 2000, 2005, 2010, and 2015, we used spatial analysis tools of the InVEST model, ArcGIS and GeoDa to calculate the supply and demand of water yield service in the research area, then analyzed and evaluated the matching status of supply and demand of water yield service in the region. The results showed that: (1) The total water yield of Wei River basin in 2015 increased by 271 million m(3) compared with that in 2000, among which the water yield per unit area varies in different categories: unused landconstruction landfarm landgrass landforestwater area; (2) During the study period, water yield service was mostly deficit, and there were differences among different regions. The total supply of water yield service increased year by year, and the total demand decreased firstly and then increased. Spatially water yield service supply is high in the south and low in the north, while demand is relatively stable; (3)The number of low-low spatial matching in Wei River basin was the largest, accounting for 20.43% of the whole Wei River basin. The high-high spatial matching was mainly concentrated in Guanzhong plain, Xi `an, Shaanxi province. The high-low spatial dislocation only involved Fengxiang county of Shaanxi province in the south of the study area. The result of this study is helpful for the government to rationally allocate water resources in Wei River basin, and to ensure the high- quality and sustainable development of the ecological environment in Yellow River basin ultimately.