Dynamic land cover and ecosystem service changes in global coastal deltas under future climate scenarios

Abstract

Coastal deltas, housing 4.5% of the global population, face profound shifts due to climate change and intensified human activities. This study utilizes the Patch-generating Land Use Simulation (PLUS) for detailed land cover dynamics and the Integrated Valuation of Ecosystem Services and Trade-Offs (InVEST) models for ecosystem services assessment, focusing on 46 global coastal deltas under future scenarios (SSP126, SSP245, SSP585). Our findings reveal a 145% increase in urban areas from 1995 to 2015, with expected continuations in urban sprawl. Grassland and barren areas are projected to diminish by up to 15% and 5%, respectively, with urban areas potentially expanding by up to 39% across scenarios. Significant decreases in surface water yield under SSP245 and SSP585 could challenge water sustainability. Moreover, a universal decline in carbon storage necessitates enhanced carbon sequestration strategies. Soil retention is anticipated to decline, leading to increased erosion risks, while habitat quality varies, improving in 29 deltas under SSP126 but worsening in 33 under SSP245 and SSP585. These insights underscore the urgency of strategic, adaptive land use planning to bolster ecosystem services, directly supporting the United Nations' Decade of Ocean Science for Sustainable Development and advancing global sustainable delta management.