Priority protected areas for mangrove conservation in coastal Guangdong, China: Addressing climate and land cover changes

Mangroves are critical for mitigating climate change, yet face challenges from climate change and land cover alterations. Identifying priority protected areas (PPAs) for mangroves and predicting their responses to climate and land cover changes is critical for mangroves to cope with future challenges. Recent studies have attempted to identify PPAs for mangroves, but most rely on current and/or historical data, and focus on examining individual drivers (climate or land cover change), overlooking a forward-looking assessment of their combined effects. Building on a novel framework integrating MaxEnt and InVEST, this study identifies mangrove PPAs influenced by climate and land cover changes and explores their spatial-temporal variations from 2020 to 2050 through land cover dynamic prediction under three shared socioeconomic pathway (SSP) scenarios (SSP126: low-emission scenario; SSP245: mid-emission scenario; SSP585: high-emission scenario). An empirical analysis is conducted in Guangdong, China. From 2020 to 2050, mangrove PPAs exhibit distinct trends under diverse scenarios, influenced by climate and land cover changes. Under the SSP126 scenario, PPAs are expected to expand and become less fragmented; while they will contract and become more fragmented under the SSP245 scenario and especially the SSP585 scenarios. Moreover, the consistency between existing marine protected areas (MPAs) and mangrove PPAs is rather low. The effectiveness of existing MPAs demonstrates a slight improvement under the SSP126 scenario, but weaken their effectiveness under the SSP245 and SSP585 scenarios. Proposals to conserve mangroves by enhancing the existing MPA system are presented to address challenges brought by climate and land cover changes.