Assessment of wetland ecological restoration effect based on fuzzy analytic hierarchy process: a case study of Tianjin Qilihai Wetland

Scientific evaluation of the effectiveness of ecological restoration could provide support for sustainable management and protection of wetlands. However, due to the multiple and difficult to quantify factors affecting wetlands, commonly used spatiotemporal evaluation methods were difficult to scientifically reflect the actual effectiveness of ecological restoration. This paper took Tianjin Qilihai Wetland, a representative wetland in northern China, as the research object. Two representative time points, 2017 (before the start of the 2-year restoration project) and 2023 (4 years after the completion of the restoration project), were selected to construct a three-level monitoring and evaluation index system containing eight specific indicators from three aspects-water environment, biological community, and landscape topography. And then, a model based on fuzzy analytic hierarchy process was developed to systematically evaluate the ecological restoration effect. The evaluation results showed that after implementing a series of measures, the comprehensive evaluation index of wetland ecological environment increased by 37.68%. In addition, it was also found that compared to the water environment, the restoration of the ecosystem had a certain lag. It was recommended to further strengthen the follow-up and continuous monitoring and evaluation, as well as the monitoring and control of the stability of external water source quality. The method and model adopted in this paper further improved the theoretical and methodological system for evaluating the effectiveness of wetland ecological restoration.