北疆盐湖湿地土壤有机碳分布特征及储量

Distribution Characteristics and Reserves Estimation of Soil Organic Carbon in the Saline Wetlands in Northern Xinjiang

盐湖湿地作为陆地生态系统的重要组成部分,土壤有机碳的变化将直接影响到全球生态系统的碳平衡,而针对内陆干旱半干旱区盐湖湿地土壤碳储量研究较为缺乏。为探讨我国内陆盐湖湿地土壤有机碳分布特征及储量,通过采取新疆北部盐湖巴里坤盐湖、达坂城盐湖土壤样品以及参考前人研究成果,分析土壤有机碳和有机碳密度特征及其在土壤剖面上的分布差异,并对北疆盐湖湿地土壤有机碳储量进行估算。盐湖湿地土壤有机碳为5.07~28.86g/kg,平均含量为15.50g/kg,土壤有机碳随土层深度的增加而减小,分配比例逐渐降低,相同土层含量变异较强。盐湖湿地土壤有机碳密度1.38~6.38kg/m2,平均值为4.32kg/m2,高于全国湿地平均水平。北疆盐湖湿地面积4 138.37km2,0~100cm土壤有机碳储量约为1 034.95×108 kg。盐湖湿地土壤平均碳密度约为全国水平的两倍,表明内陆盐湖湿地土壤是一个巨大的有机碳库。内陆盐湖湿地土壤有机碳分布特征与储量的研究,将为干旱半干旱区湿地生态系统碳循环研究以及适应气候变化的生态系统管理提供基础数据。

As an important part of terrestrial ecosystem,the change of soil organic carbon will directly affect the carbon balance of the global ecosystem,but the study on soil carbon storage of saline wetland in arid and semi-arid inland areas is less.In order to study the distribution and storage of soil organic carbon in inland saline wetland in China,the soil samples of Barkol salt lake and Dabancheng salt lake in northern Xinjiang were adopted and the previous research results were consulted.The characteristics of soil organic carbon and organic carbon density and their distribution in soil profile were analyzed,and the soil organic carbon reserves in saline wetland in northern Xinjiang were estimated.The results showed that the average content of the soil organic carbon in northern Xinjiang saline wetlands was 15.50 g/kg,which was between5.07-28.86 g/kg.Soil organic carbon decreased with the increase of soil depth,allocation proportion decreased gradually,and the content of the same soil layer varied rather strongly.The density of organic carbon in the soil of saline wetlands was between 1.38-6.38 kg/m2,with an average of 4.32 kg/m2,which was higher than the national wetlands＇ average content（2.24 kg/m2）.The area of saline wetland in northern Xinjiang was 4 138.37 km2 and it was estimated that soil organic carbon storage between 0-100 cm was about 1 034.95×10^8 kg.The average carbon density of saline wetland in northern Xinjiang was about two times that of the national level,showing that the soil in the inland saline wetlands in our country was a huge organic carbon pool.The research on the distribution characteristics and reserves of soil organic carbon in the inland saline wetlands can provide data for the research on carbon storage and carbon cycle of wetlands＇ ecosystem management in arid and semiarid areas.