Abstract:Weihe River basin, as the largest tributary of the Yellow River basin, is one of the key ecological protection built-up areas. The study on ecosystem services is conducive to the realization of the balance between high-quality development and ecological protection in the basin, to the maintenance the ecosystem service function of the basin, and to the promotion the restoration of the basin ecosystem. Based on the InVEST model, this paper analyzed the spatial-temporal dynamic changes of land use and ecosystem services of main and tributaries in the Weihe River basin from 2000 to 2018, and used correlation analysis to analyze the trade-offs and synergies among the balance of water conservation, soil conservation, and biodiversity. The results showed that the land use in the study area was mainly cultivated land, grassland, and forest land, accounting for more than 95% of the total area. Water conservation in the basin showed a trend of "increasing first and then decreasing", with an average grid unit yield of 542.9 mm. The water conservation in the Weihe River basin was higher than that in Jing River basin and Beiluo River basin, which were 6.88×108, 5.04×108, 3.36×108 m3. The soil in the basin remained patchy and the overall soil erosion status of the basin was slight. Moreover, the soil erosion in the main stream of Weihe River basin was greater than that in Jing River basin and Beiluo River basin, which were 6.67×108, 3.13×108, 6.22×108 t. The biodiversity showed that the areas with high habitat quality were concentrated in the forest ecological protection areas with good ecology and the habitat quality was poor in the areas with dense human activities. During the study period, there was a highly synergistic relationship between water conservation, soil conservation, and ecological quality in Weihe River basin, while other ecosystem services were not significant. It can be seen from the correlation that different land use types have different values of tradeoffs and collaborative contributions to ecosystem services.