阿尔泰山多年冻土区泥炭沼泽有机碳储量估算及其影响因素

Estimation of Organic Carbon Stocks and Their Influence Factors in the Permafrost Peatlands of the Altai Mountains

多年冻土区泥炭是全球重要的有机碳储存库,由于不同区域泥炭厚度以及计算时采用的间隔分辨率的不同,导致对全球多年冻土区泥炭地碳储量的估算不够精确。以新疆维吾尔自治区阿尔泰山3处典型多年冻土区泥炭剖面为研究对象,结合不同泥炭厚度,估算不同分辨率(2 cm、4 cm、8 cm和16 cm)下泥炭沼泽的单位面积有机碳储量,揭示3处泥炭沼泽单位面积有机碳储量的差异特征及其影响因素。研究结果表明,采用不同分辨率估算的泥炭沼泽碳储量存在明显差异,分辨率越低,估算结果的相对精度损失越大,泥炭沼泽单位面积碳储量的评估值越高;泥炭厚度越小,其碳储量估算受分辨率的影响越大。2 cm分辨率下的估算结果表明,新疆阿尔泰山黑湖泥炭沼泽有机碳储量为3585.6 t/hm^(2),哈拉萨孜泥炭沼泽有机碳储量为2697.1 t/hm^(2),三道海子泥炭沼泽有机碳储量为734.9 t/hm^(2);与其他地区相比,阿尔泰山多年冻土区泥炭沼泽固碳潜力巨大,区域气候模式、水热条件、植被等局地因素是影响不同泥炭沼泽单位面积有机碳储量差异的主要因素。

Peatlands in permafrost regions are important global reservoir of organic carbon.However,the estimation of carbon storage of permafrost peatlands is not accurate enough due to the differences in peat thickness in different regions and the interval resolution used in the calculation.In this study,peat profiles from three typical peatlands in the permafrost regions of the Altai Mountains in Xinjiang,were taken as objects for estimating peat organic carbon stocks and its influence factors.According to different peat thicknesses and calculation with different depth resolutions(2 cm,4 cm,8 cm and 16 cm),we found that different resolutions led to significant difference in the estimation of organic carbon stocks per unit area of peatlands.The lower resolution could cause the greater relative loss of estimation accuracy,resulting in overestimation of peatland carbon stock.The smaller thickness of peat led to greater influence on resolution accuracy of carbon stock estimation.The estimation results with 2 cm resolution showed that the organic carbon stocks were 3585.6 t/hm^(2)in the Heihu peatland,2697.1 t/hm^(2)in the Halasazi peatland,and 734.9 t/hm^(2)in the Sandaohaizi peatland in the Altai Mountains of Xinjiang.Compared with other regions,permafrost peatlands in the Altai Mountains have greater carbon sequestration potential,and regional climate patterns,local hydrothermal conditions and vegetation are the major factors affecting organic carbon storage per unit area in different peatlands.