Analysis of intrinsic value and estimating losses of “blue carbon”in coastal wetlands:a case study of Yancheng, China

Introduction:Large stocks of“blue carbon”exist in the ecosystems of coastal wetlands.This paper presents a case study of the Chinese city of Yancheng.First,through field surveys and laboratory analysis,changes in the organic carbon(OC)content in typical plant communities throughout the study area are described in detail.Second,an OC burial rate and economic value model is constructed to analyze the composition of the carbon sink values.Outcomes/other:The results are as follows:Of the typical plant communities,Spartina alterniflora has the highest OC content(5.80 g·kg-1),followed by Suaeda glauca(4.78 g·kg-1)and Phragmites australis(3.76 g·kg-1);the contemporary OC sedimentation rates are 2.01,1.48,and 1.22 cm·yr-1,respectively.Spartina alterniflora communities have the highest annual average carbon sink value($418.74/ha)in the study area,followed by Phragmites australis($176.29/ha)and Suaeda glauca($101.54/ha).Discussion:As a result of both the expansion of the Spartina alterniflora area and coastal erosion,the total OC value since 1987 has displayed two-stage characteristics:it first increased and then decreased.Conclusion:In recent years,the annual average decline in OC value has ranged from approximately$82,100 to$123,100(reference:the Sweden carbon tax provided by the World Bank,130$/ton)