Abstract:

Soil carbon stock plays an essential role in global greenhouse effect and global carbon circulation.This paper statistically calculated the soil organic carbon storages and densities for 0~20,0~100,0~180 cm depth in the Yangtze Delta region based on 1∶250 000 multipurpose regional geochemical survey and interrelated research by ARCGIS9.2 and statistical software SPSS13.0.The soil organic carbon storage and density for 0~20 cm depth are calculated as 238.65 Tg, 3.28±0.92 kg/m2,and mean densities of various soil types range 2.63~3.57 kg/m2.The soil organic carbon storage and density for 0~100 cm depth are 822.76 Tg,11.30±3.48 kg/m2,and mean densities of various soil types range 9.35~11.94 kg/m2.The soil organic carbon storage and density for 0~180 cm depth are 1245.72 Tg,17.11±7.04 kg/m2,and average densities of various soil types range 14.27~18.00 kg/m2.Compared with the data of second national soil survey in early 1980s,the mean densities for 0~20 cm and 0~100 cm depth soil in this region rise,soil organic carbon storages increase,and the soil demonstrated the carbon sink effect.The lately evaluation of soil organic carbon storages extends to greater soil depth,which could contribute to baseline data to evaluate regional carbon sequestration potential and to understand carbon circulation thoroughly.