Spatiotemporal Dynamics of Ecosystem Services Under Land Use and Climate Change Scenarios on Hainan Island, China

Understanding the spatiotemporal dynamics and driving mechanisms of ecosystem services in response to land use change is critical for regional ecological security and sustainable development, especially under the combined pressure of intensive human activities and future climate change in tropical regions. Existing studies often lack an integrated framework for multi-scenario simulation, multi-dimensional ecosystem service quantification, and spatial driving factor identification. To support sustainable management, this study focused on Hainan Island and utilized land use data from 2000 to 2025. The Markov-Patch-generating Land Use Simulation (PLUS) model was employed to simulate land use patterns for 2050 under historical trend, SSP1-1.9, and SSP5-8.5 scenarios, incorporating future climate data. The Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model was used to quantify habitat quality, carbon storage, water yield, and soil conservation. The Multi-weighted Entropy Ecosystem Service Index (MEESI) was established to evaluate ecosystem service performance. Furthermore, the GeoDetector model was applied to assess the explanatory power of the Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), Normalized Difference Built-up Index (NDBI), and Bare Soil Index (BSI) on ecosystem service dynamics. The results indicated that: (1) during 2000–2025, land use change in Hainan Island was dominated by forest-to-cropland conversion and impervious surface expansion, while future suggestions included stronger ecological protection under SSP1-1.9 and greater ecological pressure under SSP5-8.5; (2) during 2000–2025, habitat quality and carbon storage generally declined, whereas water yield and soil conservation increased, and SSP1-1.9 maintained higher overall ecosystem service performance (habitat quality = 0.6207, carbon storage = 327.89 × 106 t, and MEESI = 0.3509) than the historical trend and SSP5-8.5 scenarios in 2050; and (3) NDVI exhibited the strongest explanatory power for ecosystem service variation, whereas NDBI showed the weakest. These findings suggest that ecosystem management should consider the trade-offs and synergies among multiple ecosystem services rather than focusing on a single service. This study provides a systematic and spatially explicit framework for ecosystem service assessment under future scenarios. The study can also support scientific land use optimization, ecological conservation, and sustainable management decisions in tropical island regions.