湖北省土壤有机碳垂直分布及储量估算

Vertical Distribution and Storage Estimation of Soil Organic Carbon in Hubei Province

土壤有机碳空间分布和储量估算是全球碳循环和气候变化的关键研究领域之一。该文利用湖北省第2次土壤普查资料,研究了省内13种土壤类型地表以下1 m内的有机碳的含量、密度和容重的垂直变化规律,并估算分层(5层)和整体的有机碳储量。结果表明:对研究的所有类型的土壤,它们的有机碳的含量和碳密度均随土壤深度增加而下降,容重随深度增加而变大;湖北省有机碳储量总量为1.1Pg,其中表层土壤为0.385 Pg,占总有机碳储量的35%;所研究的13种土壤类型中,紫色土的有机碳碳密度最小(为3.41 kg/m^2),山地草甸土最大(为32.46 kg/m^2),全省平均碳密度为12.87 kg/m^2,高于全国平均水平(10.53 kg/m^2),说明湖北省植被覆盖率较高,土壤有机质积累较多,有利于生态改善和农业生产。

Carbon distribution and storage estimation are one of the key issues in the researches of carbon cycling and global climate change impact. Data of the second soil survey in Hubei Province were used to investigate the vertical variations of the concentration, density, and bulk density of organic carbon in soil layer in-depth down to 1 meter. And the organic carbon storages at different depth(stratified into 5 layers) and overall layer(1 meter in depth) for the total 13 soil types in Hubei Province were also estimated. The results showed that for all soil types, with increasing soil depth, the organic carbon concentrations and organic carbon density decrease, and their bulk densities increase. Total organic carbon storage of the Province is 1.1 Pg,in which the storage in surface soil is 0.385 Pg, accounting for 35% of the total storage. For the all studied 13 soil types,the maximum and minimum organic carbon densities are mountain meadow soil and purple soil, their organic carbon density are respectively 32.46 and 3.41 kg/m^2. The average carbon density is 12.87 kg/m^2, higher than that of the national level(10.53 kg/m^2), implying a higher coverage of vegetation, and denser accumulation of organic matter in the Province, which is beneficial to ecological system and agricultural production.