Dynamic simulation and coupling coordination evaluation of water footprint sustainability system in Heilongjiang province, China: A combined system dynamics and coupled coordination degree model

With the development of the social economy, a reasonable evaluation of the sustainable utilization capacity of water resources (WR) is of great significance to alleviate the pressures of water shortages and pollution faced by cities. This study first proposed a water footprint sustainability (WFS) system using system dynamics to evaluate the influence of WR on the environment, economy, and society of Heilongjiang province. The WFS assessment used a comprehensive evaluation method, and the coupling coordination degree model was applied to analyze the coupling coordination of the WFS system. The results showed a fluctuating increase tendency in the total water footprint (WF), blue WF, green WF, agricultural WF, and ecological WF from 2000 to 2019. However, the gray WF, domestic WF, and industrial WF presented a fluctuating decrease. The prediction for the next 30 years indicated that the green WF, agricultural WF, and domestic WF would be stable while the other indicators would increase with time. The blue water shortage degree was greater than 1; however, the green water scarcity index and water pollution degree were less than 1. The economic sustainability of the total WF, blue WF, and gray WF increased year by year; however, the social sustainability of the total WF gradually weakened. In addition, the water supply and demand ratio was below 1. Overall, the regional WFS worsened, and the coupling degree and coupling coordination degree of the WFS system varied in the range of 0.85-0.91 and 0.28-0.31, respectively. This study was of great significance in realizing the sustainable management of regional WR.