Spatiotemporal Evolution of Ecosystem Service Value and Landscape Ecological Risk and the Construction of Ecological Zoning Based on Land-Use Changes

Land-use change poses a growing threat to ecological security, yet existing regional assessments often rely on a single ecological indicator and lack direct linkage to territorial spatial planning. This study develops an integrated ESV–ERI framework coupled with quadrant zoning to provide spatially explicit, planning-compatible guidance for ecological protection in tropical island regions. Taking Hainan, China, as a case study, this research draws on land-use data from 1994 to 2024, applying ESV and ERI assessments coupled with Z-score standardization to examine their spatiotemporal evolution characteristics. The results indicate the following: (1) forest land persistently dominated land use (>63%), while construction land expanded by 197.68% and forest land and grassland decreased by 9.36% and 93.78%, respectively. (2) ESV showed a downward trend, decreasing by 14.683 billion yuan, with forest land accounting for over 83% of total ESV. Spatially, ESV exhibited a “high inland, low coast” pattern, with high-value zones across inland water bodies and central nature reserves and low-value zones in coastal urban agglomerations. (3) ERI increased from 0.0371 to 0.0539, with low-risk zones in the middle mountains and high-risk zones around the island. (4) Based on the dual dimensions of ESV and ERI, the entire island was delineated into four ecological zones. These findings provide scientific decision support for territorial spatial planning and differentiated ecological protection in tropical island regions.