Predicting the mangrove adaptability and resilience to sea level rise and quantifying anthropogenic exposures: A case study in Guangdong, China

Mangrove forests possess the capacity to respond to sea level rise, which can be decomposed into adaptability and resilience. Adaptability is primarily measured by the suitable habitat area of mangroves following landward migration, while resilience refers to the ability of mature mangrove forests to maintain their original distribution and functions under sea level rise. However, existing research rarely distinguishes between adaptability and resilience, nor explicitly differentiates the impacts of anthropogenic pressures on these two aspects. This study developed an integrated framework using Sea Level Affecting Marshes Model (SLAMM) to predict mangrove adaptability and resilience under sea level rise sea level rise scenarios and Geographical Detectors for Assessing Spatial Factors (GeoDetector) to assess their exposure to anthropogenic disturbances. The research focused on Guangdong Province, the largest mangrove area in China, and provided projections for 2070 under the RCP4.5 and RCP8.5 scenarios. The results suggest that under the combined effects of sea level rise and coastal land use, mangrove resilience would decline more markedly than adaptability. By 2070, suitable mangrove habitat is projected to decline to 49.73%–72.01% of the current extent, with only 31.26%–68.67% of the present mangrove area persisting as resilient mangroves. A significant portion of the lost mangroves would consist of highly diverse, mature mangrove communities. Furthermore, the spatial distribution of terrestrial anthropogenic pressures, primarily from aquaculture ponds and industrial centers, would exert differential impacts on mangrove responses. Aquaculture would mainly affect mangrove adaptability, while industrial development would primarily influence mangrove resilience. By 2070, 28.89%–40.23% of the suitable mangrove habitats would be subjected to high levels of anthropogenic pressure, compared to only 0.92%–2.08% of the resilient mangroves. The study’s findings suggest that enhancing mangrove adaptability and resilience in response to sea level rise will require differentiated approaches and measures. The proposed framework, which can be adapted to mangrove habitat studies in other regions with appropriate local datasets, provides practical tools for the adaptive management of mangrove ecosystems under global change.