Storage and Distribution of Soil Organic Carbon in Inner Mongolia

Based on 461 soil profiles from various data sources of Inner Mongolia,the soil organic carbon density(SOCD) and reserves(SOCR) of 0-20 cm and the whole profile in Inner Mongolia are estimated.The spatial distribution of SOCD was mapped within ArcGIS and the factors affecting SOCR and its distribution were discussed.It was found that the soil organic carbon density in 0-20 cm of Inner Mongolia is between 0.63 and 15.93 kg · m-2,and the average is 3.68 kg · m-2.Whereas the carbon density of the whole profile is between 0.22-68.77 kg · m-2 and the average is 10.35 kg · m-2.There are differences among the soil types for this value.And the SOCR in 0-20 cm of Inner Mongolia are 4.10 Pg.Meanwhile,SOCR of the whole profile are 10.79 Pg.SOCD is controlled by various geographical factors such as temperature,precipitation,vegetation and land use type etc.Estimation result showed that when mean annual temperatures rise by 1℃,the release of soil organic carbon in Inner Mongolia region is about 0.91 Pg.