<p>An important prerequisite for the realization of ecosystem services (ESs) and human welfare is the scientific assessment of ESs and their trade-offs and symbiotic relationships. The system dynamics (SD) and patch generation land use simulation (PLUS) models were coupled based on the SSP-RCP scenario in CMIP6 to predict the land use status of Jiangxi Province in 2035. A combination of the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model has been applied to assess the dynamics of soil retention (SR), carbon sequestration (CS), habitat quality (HQ) and water yield (WY), as well as to analyze the trade-offs and synergies between ESs. Redundancy analysis (RDA) is then used to unveil the variables that affect each ES.The results were obtained: (1) From 2000 to 2020, CS decreased by 0.255 × 10⁸ t, HQ decreased by 0.018, SR decreased by 0.516 × 10⁸ t, and WY decreased by 0.140 × 10¹⁰ m³. (2) Under the SSP245 scenarios, CS, HQ, and SR decreased, while WY increased. CS, HQ, and SR decreased significantly in the SSP585 scenarios. Under the SSP126 scenarios, CS and WY increased. (3) On the whole, there was a tradeoff relationship between HQ and WY in Jiangxi Province, and a synergistic relationship between other ESs. Under the SSP245 and SSP585 scenarios, the synergistic relationship between CS and HQ was significantly enhanced. The tradeoff between HQ and WY was enhanced under the SSP126 scenarios. The results are helpful in understanding the relationship between ESs and offer a reference to Jiangxi’s ecosystem protection in Jiangxi. (4) There are two main factors affecting WY, precipitation and land use disturbance intensity, for SR, slope and precipitation, for CS, DEM and slope, and for HQ, DEM and land use disturbance intensity.</p>