大兴安岭天然沼泽湿地生态系统碳储量

Carbon storage of natural wetland ecosystem in Daxing′anling of China

采用碳/氮分析仪测定法与标准木解析法,研究大兴安岭5种典型天然沼泽湿地(草丛沼泽、灌丛沼泽、毛赤杨沼泽、白桦沼泽和落叶松沼泽)的生态系统碳储量(植被和土壤)、净初级生产力、植被年净固碳量及其沿沼泽至森林方向过渡带水分环境梯度的分布格局,揭示其空间变异规律性,并定量评价寒温带5种典型天然沼泽湿地的碳储量与固碳能力及其长期碳汇作用。结果表明:①5种天然沼泽湿地的植被碳储量分布在(0.48±0.08)—(8.33±0.66)kgC/m2之间,沿过渡带环境梯度呈递增趋势;②土壤碳储量分布在(19.21±6.17)—(38.28±4.86)kgC/m2之间,沿过渡带环境梯度却呈递减趋势;③生态系统碳储量分布在(27.54±7.16)—(38.76±4.58)kgC/m2之间,沿过渡带环境梯度基本呈恒定分布规律性,且以湿地土壤碳储量占优势地位(69.8%—98.8%);④植被净初级生产力分布在(0.68±0.10)—(1.08±0.12)kg.m-.2a-1之间,毛赤杨沼泽最高,草丛沼泽、灌丛沼泽、白桦沼泽居中,落叶松沼泽最低,且总体上低于温带森林湿地而高于寒温带天然落叶松林;⑤植被年净固碳量分布在(0.32±0.09)—(0.51±0.06)kgC.m-.2a-1,毛赤杨沼泽最高(高于全球植被平均年净固碳量)、灌丛沼泽和白桦沼泽居中(达到或接近全球平均值)、草丛沼泽和落叶松沼泽最低(略低于全球平均值),故这5种沼泽湿地均属于碳汇功能相对较强的湿地植被类型。

The ecosystem carbon storage（vegetation C storage and soil organic C storage）,carbon sequestration and net primary productivity of five types of natural wetland（hassock wetland,shrubs wetland,Alnus sibirica var.hirsuta wetland,Betula platyphylla wetland and Larix gmelinii wetland） were studied by using Multi N/C 3100,HT 1300 Solids Module（Analytik Jena AG,Germany） and the sample tree analysis method in Daxing′anling of northeast China,so as to evaluate the carbon sinks of natural wetlands quantitatively and reveal the influences of environmental gradients on wetland carbon sinks.The results showed that： ①The vegetation carbon storage of five wetland types varied from（0.48±0.08） to（8.33±0.66） kg C/m2,which took on rising trends along the water environmental gradient from marsh to forest;②The soil organic carbon storage of five wetland types varied from（19.21±6.17） to（38.28±4.86） kg C/m2,which took on lowering trends along this environmental gradient;③The ecosystem carbon storage of these wetland types varied from（27.54±7.16） to（38.76±4.58） kg C/m2,which nearly took on constant trends along this environmental gradient,and the soil C pool all dominated in five kinds of ecosystem C pool（69.7%—98.8%）;④The net primary productivity（NPP）of five wetland types varied from（0.68±0.10） to（1.08±0.12） kg · m-2 · a-1,NPP of Alnus sibirica var.hirsuta wetland was the highest,that of Larix gmelinii wetland was the lowest,and NPP of others were in the middle level,and they generally were lower than that of the temperate forested wetlands,but higher than that of the cold temperate larch forest;⑤The vegetation net carbon sequestration（VNCS） of five wetland types varied from（0.32±0.09） to（0.51±0.06） kg · m-2 · a-1,and VNCS of Alnus sibirica wetland was the highest（which was higher than the average of global vegetation net carbon sequestration）,VNCS of shrubs wetland and Betula platyphylla wetland were in the middle level（reached or approached the average VNCS of global vegetation）,VNCS of hassock wetland and Larix gmelinii wetland were lowest（but slightly lower than the average VNCS of global vegetation）,therefore,five types of natural wetlands all have strong carbon sink function in Daxing′anling of northeast China.