长江口滨海湿地有机碳循环过程及影响因素研究进展

Advances in Organic Carbon Cycle Processes and Influencing Factors of Coastal Wetlands in the Yangtze River Estuary

摘要:

滨海湿地是“蓝碳生态系统”的重要组成部分。综述了长江口滨海湿地土壤有机碳时空分布及含量、碳汇速率、有机碳横向输入输出通量及量化方法、有机碳循环定量分析模型以及有机碳储量和组分对不同影响因素所做出的动态响应规律，发现在土壤有机碳水平空间分布上，崇西湿地＞崇明东滩＞九段沙＞南汇潮滩；有机碳通量和浓度变化主要受到植物生物量和结构、水和土壤的理化性质、陆源输入和潮汐动力、间隙水交换以及人类活动和全球气候变化的影响。未来应加强长江口湿地土壤碳库和有机碳输运通量统一观测，准确量化各主要因素对有机碳的贡献，这对研究盐沼湿地的碳循环机理和碳汇评估具有重要意义。

关键词:长江口湿地;有机碳时空分布;垂向埋藏速率;横向输送通量;影响因素;碳汇评估

Abstract:

Coastal wetlands are an important part of the “blue carbon ecosystem”. The spatiotemporal distribution and content of soil organic carbon of the coastal wetlands in the Yangtze River Estuary， the carbon sequestration rate， the lateral input and output fluxes of organic carbon and the quantification methods， and organic carbon circulation quantitative analysis model are summarized. The dynamic response of organic carbon storage and composition to different influencing factors is analyzed. It is found that the horizontal distribution of soil organic carbon ranks as Chongxi Wetland > Chongming Dongtan > Jiuduansha > Nanhui tidal flat； Organic carbon flux and concentration changes are mainly affected by water and soil physicochemical properties, terrestrial inputs and tidal dynamic, porewater exchange, human activities and global climate change. In the future， the uniform observation of the soil carbon pools and organic carbon transportation in wetlands of the Yangtze River Estuary should be strengthened， to accurately quantify the contribution of the main factors to organic carbon， which is of great significance to the study of the carbon circulation mechanism and carbon sink assessment of saltmarsh wetlands.

Key words:Yangtze River Estuary wetland;spatiotemporal distribution of organic carbon;vertical burial rate;lateral transport fluxes;influencing factors;carbon sink assessment