长江三角洲地区土壤有机碳库研究

土壤碳库变化对于全球温室效应、全球碳循环有重大的影响。基于新近完成的1：250 000多目标地球化学调查及相关研究成果，运用地理信息系统软件ARCGIS 9.2、统计软件SPSS13.0，对长江三角洲地区0~20、0~100、0~180 cm深度土壤有机碳密度及储量作出实测统计。结果表明:长江三角洲地区0~20 cm土壤有机碳库储量为238.65 Tg，有机碳密度为3.28±0.92 kg/m2，各类型土壤有机碳密度均值介于2.63~3.57 kg/m2；0~100 cm土壤有机碳库储量为822.76 Tg，有机碳密度为11.30±3.48 kg/m2，各类型土壤有机碳密度均值介于9.35~11.94 kg/m2；0~180 cm土壤有机碳库储量为1 245.72 Tg，有机碳密度为17.11±7.04 kg/m2，各类型土壤有机碳密度均值介于14.27~18.00 kg/m2。与第二次土壤普查比较，全区0~20、0~100cm土壤有机碳密度均值都表现为上升趋势,有机碳库储量增加，土壤表现为碳汇功能。提供了新的土壤碳库实测统计信息，为研究中国区域土壤碳固定潜力、深入全面理解区域碳循环提供基准数据。

STATISTICAL CALCULATION OF SOIL CARBON STORAGES IN THE YANGTZE DEITA REGION

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.