Community structure and carbon storage of mangrove forests in Hainan Island, China affected by their patch characteristics
Résumé
Mangrove forests function as an important carbon reservoir in mitigating climate change. However, they are threatened by several anthropogenic activities along the coastlines. In fact, global mangrove deforestation has largely reshaped spatial patterns of mangrove distribution, thus affecting this carbon reservoir. Changes in patch characteristics can further influence the community structure and carbon storage of mangrove forests. This study is based on the land use/cover data obtained from Operational Land Imager image interpretation, as well as the community structure and carbon storage data from field quadrat investigation and sampling of mangrove forests in Hainan, China. This study mainly discusses the effects of terrestrial land use/cover change on mangrove distribution and explores how community structure and carbon storage could be influenced by patch area and patch perimeter, notably. Results indicated that the total area of mangrove forests was positively correlated with the increasing rate of constructed land, and the Shannon diversity index was positively related to the decreasing rate of cultivated land. This would suggest that urbanization could benefit mangrove protection and recovery. The policy of "Converting Arable Land Back to Forests" in China has positively contributed to the increase in biodiversity. Results of the regression analysis revealed that stem diameter at breast height, tree density, Shannon diversity index, biomass carbon storage, soil carbon storage, and total carbon storage were significantly influenced by both the area and perimeter of mangrove patches. Ecosystem carbon storage, including biomass and soil carbon, decreased with the patch area and patch perimeter of mangrove forests, with edge effects having a substantial impact. This study underlined that future mangrove restoration, rehabilitation and protection efforts should attach great importance to the significant impact of the spatial distribution pattern of mangrove forests on their carbon sink function.
