Conceptual model of ecosystem service flows from carbon dioxide to blue carbon in coastal wetlands: An empirical study based on Yancheng, China

Abstract

Large amounts of blue carbon exist in the ecosystems of coastal wetlands. Accurate calculations of the stocks and economic value of blue carbon in various plant communities can facilitate vegetation rehabilitation. Based on this objective, first, a blue carbon estimation model was constructed by combining a Carnegie-Ames-Stanford Approach (CASA) model, and second, the distribution pattern of blue carbon and flow direction of ecosystem services (carbon sequestration) in a coastal wetland in China was analyzed utilizing a combination of field surveys, remote sensing data, and laboratory analysis techniques. Finally, the wetland carbon sequestration value and its income-expenditure status were measured using the carbon tax method. The results show that the aboveground net primary productivity of coastal wetland vegetation exhibits a non-zonal distribution in the south-north direction, whereas it presented a three-level gradient distribution, characterized as “low (200–300 g/m2·y)–intermediate (300–400 g/m2·y)–high (400–500 g/m2·y)”, in the east-west direction. The accumulation of carbon gradually increased from the ground surface to the underground (litter < underground roots