Evaluation and tradeoff‐synergy analysis of ecosystem services in Luanhe River Basin

Abstract The evaluation of watershed ecosystem services and the research on their trade‐offs and synergies are of great significance for the rational formulation of environmental policies. Taking Luanhe River Basin as an example, based on InVEST and CASA models, the temporal and spatial distribution characteristics of the water yield, soil conservation and carbon sequestration in 1990, 2000, 2010 and 2015 were analysed, where correlation analysis was utilized to explore the tradeoff‐ synergy relationship among various ecosystem services. And by mapping the hotspots of the ecosystem services, the spatial differences of ecological environment conditions were revealed in Luanhe River Basin. The results show that (1) from 1990 to 2015, water yield and soil conservation declined in a fluctuating manner, and carbon sequestration first decreased, then increased. The three services all showed a pattern of increasing gradually from northwest to southeast in space. (2) The relationship between the ecosystem services showed that water yield and carbon sequestration were mainly in a trade‐off relationship, while water yield and soil conservation, soil conservation and carbon sequestration were mainly in synergistic relationships. In different regions, trade‐offs and synergies changed to different degrees, showing obvious spatial heterogeneity. (3) The southeastern part of the study area was the main hotspot for ecosystem service supply. From 1990 to 2015, the areas of non‐hotspots showed a decreasing trend. Ecosystem service hotspots have expanded, and overall ecological environment has improved significantly, but ecological environment has been degraded in some areas.