Risk assessment and configuration of water and land resources system network in the Huang-Huai-Hai watershed

Abstract

Under the influence of global warming and human activities, the risk sources of land and water resources system networks are complex and uncertain, which has induced a series of ecological and environmental problems. It is of great significance to systematically identify and evaluate the risks of water and land resources system networks from the perspective of water resource attributes and land resource attributes. Therefore, based on the mutual feedback mechanism of water and land resources, this study constructs the water and land resources system network in the Huang-Huai-Hai Watershed. The cluster analysis-ISODATA algorithm and entropy weight-TOPSIS evaluation method were used to evaluate and predict the risk of the water and land resources system network in the Huang-Huai-Hai Watershed. In addition, a model for the optimal allocation of water and land resources for risk mitigation was constructed, and the optimal allocation scheme of water and land resources in the Huang-Huai-Hai Watershed in 2030, 2035 and 2060 under different scenario modes was obtained. The results show that the risk of the water and land resources system network in the Huang-Huai-Hai Watershed from 1990 to 2020 first increased and then decreased, and the proportion of areas above medium–high risk in 2001–2010 was 53.17%. Compared with 2020, the area above medium–high risk in 2030, 2035 and 2060 increased by 1.4–17.38%, 6.78–15.92% and 2.39–6.82%, respectively. After the optimal allocation of water and land resources for risk mitigation, the targets of optimal allocation of water and land resources in 2030, 2035 and 2060 were improved, among which the water shortage under different scenario modes was reduced by 71.92–79.19%, 65.92–74.46% and 62.23–71.69%, and the area above medium–high risk in the water and land resources system network decreased by 48.4–59.79%, 20.99–59.7% and 29.53–49.06%, respectively. The results of this study can provide technical support for coping with global climate change, solving the problem of water shortage and optimizing the spatial layout of the land in the Huang-Huai-Hai Watershed.