Abstract: Peatland is one type of ecosystems with the strongest carbon sequestration capacity on earth, the stability maintenance of which is of great significance to the enhancement of wetland carbon sequestration capacity. We examined the stability of Jinchuan peatland, a typical peatland in Longwan National Nature Reserve, Jilin Province. The evaluation index of ecosystem stability was screened by frequency analysis and ecosystem structure-function index method. Based on analytic hierarchy process (AHP), a peatland ecosystem stability evaluation index system was established, and then was used to assess the stability of the Jinchuan peatland. The results showed that: (1) 20 indicators reflecting wetland structure, wetland function, and external environmental spatiotemporal changes were screened to construct an evaluation index system for wetland ecosystem stability. (2) The value of stability index of Jinchuan peatland was 0.84, indicating that the wetland is in a stable state. The fluctuation of wetland hydrological process caused by climate change and agricultural production was the constraint factor affecting stability. (3) The health status index of Jinchuan peatland was 63.59, indicating a sub-healthy status. In order to maintain the stability of Jinchuan peatland and keep healthy, it is suggested to implement land reclamation for returning the surrounding drylands to wetlands, or adjust the agricultural planting structure, transforming drylands into paddy fields or planting aquatic economic crops. Meanwhile, linear drainage ditches should be filled up to improve the drainage rhythm of wetlands.

Key words: ecosystem stability, analytic hierarchy process (AHP), Jinchuan peatland