Assessment and prediction of the water ecological carrying capacity in Changzhou city, China

Abstract With rapid economic development and population growth, pressure on the urban ecological environment is becoming intense, and the ecological environment carrying capacity is becoming an important issue. In this study, an index system combining the system dynamics (SD) and analytic hierarchy process (AHP) methods was constructed to assess the water ecological carrying capacity (WECC) of Changzhou city. In particular, the construction of the aquatic habitat and aquatic organism indexes were constructed and showed that water ecology health should be monitored along with the economy and population, which were focused in the past. Scientific research has neglected the internal spatial heterogeneity in administrative regions. Therefore, the SD and AHP models were applied to simulate the WECC of administrative regions and control units from 2010 to 2016. The simulation results show that the WECC of Liyang and Jintan counties reached a safe carrying capacity state, while the urban districts were in a critically overloaded state. In addition, the MIKE11 model was adopted to simulate the WECC under different inflow and the river connectivity index scenarios, and the optimal parameters for improving the WECC were obtained when the inflow recharge was 10 m3/s and the river connectivity index exceeded 60%. The prediction results from the optimized WECC showed that the WECC of all administrative areas and control units in Changzhou city reached the safe carrying capacity state. The results provide insights for improving the WECC of Changzhou city.