Impacts of vegetation establishment duration on soil organic carbon accumulation in Chongming-Dongtan, China

Estuarine tidal wetlands are highly influenced by land and sea. Some environmental factors change quickly with the vegetation establishment duration and have an important influence on the soil carbon sequestration. Based on field survey and remotely sensed data, we investigated the relationship between soil organic carbon (SOC) content, its accumulation rate and vegetation establishment duration in Chongming-Dongtan, the Yangtze Estuary. With the increase of vegetation establishment duration, SOC content increased significantly. SOC content in the vegetation establishment duration of 14 years was about 1.3 times that of 1 year. Soil organic carbon accumulation rate decreased with time and was stabilized at 11 g·m^-2·a^-1 10 years later. SOC content of tidal wetland from Yangtze Estuary was close to those of other coastal wetlands in China, but the accumulation rate was far lower than that on the east coast of the United States, probably due to human disturbance such as overgrazing and harvest. Therefore, there is a great potential for carbon sequestration enhancement by conservation and restoration of coastal wetlands.