Study on Quantitative Model of Water Resource Ecological Compensation in Yangtze River Basin Based on Water Footprint–Decoupling Analysis Methodology

Establishing a standard model for water resource ecological compensation, based on water quantity and quality, is one of the current research hotspots in the field of ecological economy. This paper calculates the water footprint from 2011 to 2021, constructs an inter-provincial water resource ecological compensation model in the Yangtze River Basin, and discusses the horizontal compensation of water resource ecology in the Yangtze River Basin. Firstly, the water footprint method and the water footprint ecological load index are used to evaluate and analyze the overall water resource utilization in the basin and in various administrative regions within the basin; secondly, the decoupling analysis method is used to study the coordinated relationship between water resource utilization and economic development among different administrative regions; finally, the identity of the compensation subject and object are determined on the basis of the calculation of ecological surplus and deficit of water resources in each administrative region, and the compensation standards are quantitatively calculated. The results indicate the following: (1) Over the 11 years, the overall water footprint of the Yangtze River Basin and its provinces has shown a growth trend, with significant differences in the quantity of water footprints among different administrative regions, and the average water footprint exhibits a decreasing distribution from “midstream—downstream—upstream”. There are significant differences in the water footprint ecological load index among provinces, with the load index showing a trend of being higher in the east and lower in the west. (2) From the perspective of the decoupling index, there has been no state of dis-coordination in the Yangtze River Basin overall over the 11 years, with 2016, 2018, and 2019 being in a high-quality coordinated state, while the other years were in a primary coordinated state. (3) In terms of horizontal payment for ecological compensation, Tibet, Yunnan, and Qinghai have consistently been regions receiving ecological compensation, while Shanghai, Jiangsu, Anhui, Hubei, Hunan, and Chongqing have been determined as compensation subjects required to make payments over the years.