Adaptive response of Dongzhaigang mangrove in China to future sea level rise.

Mangrove forests are valuable intertidal ecosystems that provide coastline protection, biodiversity maintenance, and carbon sequestration. However, their survival is under severe threat from rapidly rising sea levels. In this study, we aimed to investigate the changes in the area of the Dongzhaigang mangrove in China since the 1950s and causes of these changes using literature and remote sensing data. The impact of historical and future sea level rise (SLR) on the mangroves was analyzed using remote sensing data and climate model data under the low, intermediate, and very high greenhouse gas emission scenarios (Representative Concentration Pathways (RCPs) 2.6, 4.5, and 8.5). The area of the mangrove forests decreased from 3416 to 1711 hm during 1956-1988 and remained constant at 1711 hm after the 1990s, owing to anthropogenic disturbances such as reclamation and aquaculture before the 1980s and the protection of nature reserve establishment after the 1990s, respectively. Under RCPs 4.5 and 8.5, SLR is expected to cause > 26% of the mangroves to disappear by 2100, whereas under RCP 2.6, only 17% of the mangroves will likely be lost. Biological measures such as reestablishment of ponds as mangrove forests, afforestation, and biological embankment for sediment trapping in coastal wetlands are recommended to enhance the resilience of mangroves to SLR.