Ecological health assessment of an arid basin using the DPSIRM model and TOPSIS—A case study of the Shiyang River basin

Abstract

Rivers in arid areas play a crucial role in sustaining the basin, regional economic, ecological security and social development. Maintaining the ecological health of the basin ecosystem is the guarantee for high-quality regional development. Developing a robust and unbiased evaluation index system is pivotal for the scientific assessment of basin health. Quantitative evaluation of the ecological health of inland river basins in arid areas under the influence of human activities is a necessary condition for basin scientific management and policy formulation. This paper presents a conceptual DPSIRM model (Driving Force - Pressure - State - Impact - Response - Management), selects 33 indicators for constructing the evaluation index system, recommends the AHP (Analytic Hierarchy Process) for subjective weight assignment, utilizes the CRITIC (Criteria Importance Through Intercriteria Correlation) method for objective weight determination, and amalgamates subjective and objective weights to establish CW (comprehensive weights). On this basis, the TOPSIS (Technique for Order Preference by Similarity to an Ideal Solution) method is employed to assess the relative closeness between the health degree of the Shiyang River Basin and the ideal solution from 2000 to 2020, and the alteration in the basin’s health is judged according to the relative closeness. The results showed that the health level of the Shiyang River Basin gradually increased from 0.41 to 0.61, transformed from subhealthy to healthy. Among the six subsystems, driving force, state, impact and response health were all subhealth, while stress and management health were ideal. The analysis of the index impact weights illustrated that the average annual precipitation, urbanization rate, population density, irrigation water consumption per hectare, and water consumption per 10,000 yuan of gross domestic product (GDP) with a significant influence on the ecological health of the basin. This research demonstrated a novel analytical framework for assessing the health of inland basins in dry regions. The findings may serve as a basis for management departments to develop specific basin planning and management policies.

Keywords

• DPSIRM model
• Assessment Index System
• CRITIC
• TOPSIS
• Shiyang River Basin