Abstract: Northeast forest belt is an important ecological barrier in China. Understanding the trade-offs of ecosystem services is important to coordinate ecological environment protection and social development in this region. In this study, we used spatial autocorrelation analysis, bivariate spatial correlation analysis, and spatial clustering analysis methods to quantify the spatial patterns of six selected ecosystem services, and reveal underlying mechanisms of trade-offs and synergies and spatial variation. The results showed that the six selected ecosystem services showed a significant aggregation distribution. At regional scale, the services of water conservation, biodiversity maintenance, soil conservation and carbon sequestration showed a systematic relationship, while the services of sand fixation and food supply showed a trade-off relationship with other ecosystem services. Ecosystems provide a variety of services, and the types and quantities of ecosystem services provided by different ecosystems were significantly different. Therefore, the trade-off/synergy relationship among different ecosystem services also showed significant spatial variation. The study area was divided into ecosystem service balance zone, ecosystem service coordination zone, sand fixation zone, and food supply zone through ecosystem service clusters, in order to provide a scientific basis for the management of ecosystem services and promote the comprehensive, coordinated, and sustainable development of resources and ecological environment.

Key words: ecosystem services, trade-offs and synergy, ecosystem services cluster, Northeast China forest belt.