江西省表层土壤有机碳库储量估算与空间分布特征

Organic carbon reserves of topsoil and spatial distribution in Jiangxi province

土壤中碳较小幅度的变化能引起全球气候较大的变化，而表层土壤有机碳库易受人类活动的影响而发生变化，因此估算土壤有机碳库储量，对土壤碳库变化及土壤固碳潜力的研究具有重大意义。根据2006年江西省各县市典型土壤GPS定点采样样点的理化分析数据计算出有机碳密度并进行空间插值，利用江西省第二次土壤普查相关数据建立土壤空间数据库，结合各土壤类型分布面积，估算表层（0～20cm）土壤有机碳密度和储量，并探讨其空间分布特征。研究表明：江西省表层土壤平均有机碳密度介于2．655～6．877kg·m^-2之间，有机碳库总储量为640355．653×10^6kg，其中，仅红壤和水稻土的土壤有机碳储量已占90．71％。表层土壤有机碳密度具有高度的空间变异性，赣西、赣东如萍乡、宜春、上饶地区土壤有机碳密度较高，赣南、赣北地区如九江、赣州等地区土壤有机碳密度较低，总体上呈东西走向高，南北走向低的趋势。江西省是一个农业大省，人类干扰下的土壤碳库研究却很少，其碳库动态变化还值得进一步的探讨。

The tittle change of the soil cabom reserves can cause large change of globe climate. Human activities easily influence the change of topsoil organic carbon pool, So the calculating of topsoil reserves has significance in the study of the pool＇s change and potential. Based on a soil database from the soil sampling of Jiangxi by GPS in 2006, topsoil organic carbon density was calculated. Combined with soil map of Jiangxi Province second soil survey and areas in different soil types, Topsoil organic carbon density and reserves were estimated using geographical information system, and the spatial distribution characteristics were discussed. The result showed that the topsoil organic carbon density were from 2.655 to 6.877 kg·m^-2 and the reserves were 640 355.653×10^6 kg, Only red soil and rice soil were 90.71% of the total reserves. The amount of carbon varied significantly at different districts in Jiangxi. In the east and west of Jiangxi, like Pingxiang, Yichun and Shangrao, had high organic carbon density. In the south and north, like Jiujiang and Ganzhou, had low density. As a whole, East-west direction had high organic carbon density, South-north direction was in opposition. Jiangxi is a agricultural province, but the soil caborn researches in human activities are few. Its trends deserve to be discussed more.