中国典型湿地生态系统碳汇功能比较

A Review on Carbon Fluxes for Typical Wetlands in Different Climates of China

选择温带湿润地区三江平原湿地、青藏高原东缘若尔盖湿地和北热带向南亚热带过渡区域的广州红树林湿地,对比分析不同气候条件下湿地生态系统碳源、碳汇特征及其影响因素。研究发现,红树林湿地在固碳速率和固碳潜力方面都要高于泥炭沼泽和苔藓泥炭沼泽。不同气候条件下,湿地的CH4和CO2排放通量有较大差异。在CO2排放通量方面,若尔盖高原湿地和三江平原湿地的排放通量要高于红树林湿地;在CH4排放通量方面,三江平原湿地的CH4排放通量要大于若尔盖高原湿地和红树林湿地。不同气候条件下,湿地生态系统总体表现为碳汇。气候因素在大尺度上影响湿地的碳源、碳汇特征,而水文、植被类型和植株密度等亦是影响不同湿地类型碳源、碳汇差异的主要因素。

The three wetlands with different climatic zones were selected to compare carbon sink/source and impacting factors to carbon source.They are in the Sanjiang Plain,Zoigê Plateau and Guangzhou City located in temperate sub-humid areas,in Eastern Tibetan Plateau and in transition zone of Guangzhou between tropical and subtropical area,respectively.This study found that the carbon sequestration and potential in the mangrove wetlands are higher than those in other 2 wetlands.CH 4 and CO 2 emissions in the wetlands are varying with different climatic conditions.CO 2 emissions from the wetlands in Zoigê Plateau and the wetlands in Sanjiang Plain are higher than the mangrove wetlands in Guangzhou;and CH 4 emission in the wetlands in the Sanjiang Plain is greater than the mangrove wetlands in Guangzhou.Wetlands perform as a carbon sink even with different climatic conditions.Climate is a main driver at a large-scale for carbon exchanges for the wetlands,while hydrology,vegetation types and densities also play major roles for wetland carbon exchange.Reclamation of the wetlands impacts carbon pool significantly,because the reclamation reduces soil organic carbon storage in wetlands.