ベトナム、カマウにおけるマングローブ植生変化の時空間分析

Mangrove ecosystems provide essential coastal ecosystem services, including shoreline protection, carbon sequestration, and biodiversity conservation, but are increasingly affected by climate change, aquaculture expansion, and coastal development. These pressures have intensified marine pollution, which alters water chemistry, reduces oxygen levels, and disrupts root-sediment interactions that are crucial for mangrove survival and regeneration. This study examined spatiotemporal changes in mangrove vegetation in Cà Mau, Vietnam (2020-2024) using the Mangrove Vegetation Index (MVI) derived from Sentinel-2 imagery, combined with spatial autocorrelation metrics (Moran's I and LISA). The total mangrove area increased by 144.83 ha compared to the 2020 baseline (39,414 ha), showing distinct spatial heterogeneity. Expansion clusters (NE) of 217.3 ha were concentrated along the western and southwestern coasts (Moran's I = 0.674), driven by government-led restoration programs with sustained financial investment and strict policy enforcement, and effective institutional coordination of the successfully established coastal vegetation areas. Conversely, loss clusters (EN) of 240.6 ha were observed in the southeastern coastal areas (Moran's I = 0.655), caused by unregulated shrimp aquaculture expansion, insufficient institutional enforcement, and chronic erosion-related pollution that disrupted sediment stability and prevented natural regeneration. These contrasting patterns reflect how restoration efforts, governance gaps, and pollution-driven stress jointly influence mangrove dynamics. By integrating remote sensing and social-ecological analysis, this study identifies area-specific management strategies-policy-aligned restoration investment in the west and incentive-based monitoring systems in the southeast-are identified, providing a practical framework for sustainable coastal governance.