Abstract:

527 surface soil samples were collected and analyzed in the semiarid area in the northeast Inner Mongolia to investigate the distribution of the organic and inorganic carbon pool, its influence factors and to access the change of the carbon pool under the climate change. The results showed that the carbon pool in the study area is still dominated by the total organic carbon (TOC) with the variation of 61%-97% under different soil types. The spatial distribution of soil organic and inorganic carbon was controlled significantly by the climate conditions such as temperature and precipitation. Soil organic carbon has a trend of decreasing with mean annual temperature (MAT), but increasing with mean annual precipitation (MAP). However, soil inorganic carbon has an opposite trend of increasing with MAT and decreasing with MAP. Based on the extent of temperature and precipitation change predicted by IPCC 2007, the overall carbon density in 2090-2099 caused by the climate change will decrease by about 1.22 kg/m2.

Key words:  semiarid area, Inner Mongolia, soil carbon pool, global change