Biomass and carbon storage of Phragmites australis and Spartina alterniflora in Jiuduan Shoal Wetland of Yangtze Estuary, East China

By the methods of field survey and laboratory analysis, an investigation was conducted on the seasonal dynamics of biomass and carbon storage of Phragmites australis and Spartina alterniflora dominated vegetation belts in the Jiuduan Shoal Wetland of Yangtze Estuary, East China in 2010-2012. The organic carbon storage of the biomass (including aboveground part, underground part, and standing litter) of the two plants was the highest in autumn and the lowest in spring. The average carbon storage of the biomass of S. alterniflora per unit area (445.81 g·m^-2) was much higher than that of P. australis (285.52 g·m^-2), and the average carbon storage of the standing litter of S. alterniflora (315.28 g·m^-2) was also higher than that of P. australis (203.15 g·m^-2). However, the organic carbon storage in the surface soil (0-30 cm) under P. australis community (1048.62 g·m^-2) was almost as twice times as that under S. alterniflora community (583.33 g·m^-2). Overall, the carbon accumulation ability of P. australis community (3212. 96 g·m^-2) was stronger than that of the S. alterniflora community (2730.42 g·m^-2). Therefore, it is of significance to protect the P. australis community in terms of carbon sequestration at the salt marsh.