Objective  Ecosystem services are important for improving the quality of urban habitat and promoting ecological balance. The study of their assessment and synergistic trade-offs will help to develop more scientific and rational urban planning and management strategies.

Method Daxing District of Beijing was taken as the study area. Five indicators, i.e., food supply, carbon fixation, water conservation, biodiversity maintenance and recreation, were selected to comprehensively evaluate the ecosystem services in the study area using the indicator evaluation method and model simulation method. The spatial overlay method was used to identify hotspot areas, and the Spearman’s index and bivariate local spatial autocorrelation were used to explore the synergistic relationship between ecosystem service trade-offs. The Spearman index and bivariate local spatial autocorrelation analysis were used to explore the synergistic relationship between ecosystem service trade-offs, and the self-organized mapping method was used to identify ecosystem service clusters to classify different ecological functional zones and put forward corresponding ecological optimization strategies.

Result (1) The distribution of individual ecosystem services in Daxing District generally showed a pattern of northwest and southeast differentiation, with supply, regulation and support services showing a distribution pattern of low in the northwest and high in the southeast, and cultural services showing a high distribution pattern in the north and low in the south; hotspot areas were dominated by synergistic clustering of supply-regulation-support services, which were centrally located in Changziyang Town, Caiyu Town, and the Yongding River Basin. (2) The relationship of ecosystem service trade-offs and synergistic relationships in Daxing District was complex. The synergistic relationship between ecosystem services in Daxing District was complex, with the strongest synergistic relationship between biodiversity maintenance, water conservation, carbon sequestration and food supply, and the trade-off relationship between recreation and other services. (3) There were 6 types of ecosystem service clusters in Daxing District, which were classified into six functional districts, including watershed ecological conservation district, urban ecological restoration district, agro-ecological supply district, carbon sink ecological conservation district, greenland ecological nourishment district, and equilibrium ecological experience district.

Conclusion This paper constructs a multivariate index system for evaluating ecosystem services in urban fringe areas, discusses ecosystem service trade-offs and synergies in depth and identifies functional clustering. The research results can provide reference for ecological service evaluation methods in large and medium-sized cities, and provide planning basis and development suggestions for regions with similar current problems and development goals.