Systematic Evaluation and Influencing Factors Analysis of Water Environmental Carrying Capacity in Taihu Basin, China

Systematic evaluation of water environment carrying capacity (WECC) is a prerequisite for achieving sustainable development, which reflects the water environment comprehensive condition of lake basin under the current economic development scenario. Therefore, taking the Taihu Basin as a case study, a scientific comprehensive evaluation index system of WECC was established based on the Pressure-State-Response (PSR) assessment framework, which included water resources (WR), pollution emission (PE), water quality (WQ), water ecology (WE), and land use (LU) sub-systems. An expert group was invited to determine the weights of each indicator using the group analytic hierarchy process (G-AHP) method, and the indicators in the WR, PE, WQ, WE, and LU sub-systems were 6.5%, 21.8%, 27.9%, 11.1%, and 32.9%, respectively. According to the evaluation results, the WECC index of Taihu Basin increased by 51.4% from 2007 to 2019, but it still slightly exceeded the carrying capacity of the water environment; the water quality and pollution discharge indices had the most significant improvement. Algal blooms are a major factor challenging WECC in the Taihu Basin. Therefore, the overall restoration of the water eco-system must receive more attention in the future.

Automated summary

The evaluation of water environment carrying capacity is a prerequisite for achieving sustainable development and reflects the comprehensive condition of the water environment in a lake basin under current economic development. A comprehensive evaluation index system of water environment carrying capacity was established based on the case study of Taihu Basin, including water resources, pollution emissions, water quality, water ecology, and land use subsystems. According to the evaluation results, the water environment carrying capacity index of Taihu Basin increased by 51.4% from 2007 to 2019, but still slightly exceeded the carrying capacity of the water environment.