土地利用方式的变化在土壤有机碳(Soil Organic Carbon,SOC)积累的过程中起着非常重要的作用。目前在估算土壤有机碳储量的过程中,一直没有重视土地利用属性。运用基于土壤学专业知识的连接方法 (pedological professional knowledge-based method,PKB法),结合江苏省新沂县1∶20万土壤图,1∶20万土地利用图和1∶20万土壤类型土地利用混合图,估算了各图在不同土壤剖面点数情况下的新沂县SOC储量,并将三者在最佳剖面点数下估算出的SOC储量和SOC密度(SOCD)进行了比较及精度评价。结果表明:在土壤类型图、土地利用图和土壤类型土地利用混合图上进行的PKB法连接时最佳剖面点数均为397点,最佳网格为2 km×2 km;在中比例尺图件上进行PKB法连接估算SOC储量时,综合考虑土壤类型和土地利用类型可以大大提高估算精度,同时土地利用类型属性比土壤类型属性更为重要。研究结果可为在中比例尺条件下提高SOC估算精度提供科学依据。 Changes in land use patterns play a very important role in the accumulation of soil organic carbon (SOC). At present, in the process of estimating soil organic carbon stocks, no emphasis has been placed on land use attributes. According to the pedological professional knowledge-based method (PKB) method, with 1: 200,000 soil map, 1: 200,000 land use map and 1: 200,000 soil type land use in Xinyi County, Jiangsu Province, Mixed maps were used to estimate the SOC reserves of Xinyi County under different soil profile points. The SOC stocks and SOC densities (SOCDs) estimated from the best profile points were compared and the accuracy was evaluated. The results showed that the best cross-sectional points of PKB method were 397 points and the best grid was 2 km × 2 km in the soil type map, land use map and soil type land use mixed map. In the mid-scale map When estimating the SOC reserves by PKB method, the accuracy of estimation can be greatly improved by comprehensively considering the types of soil and land use, and the attributes of land use type are more important than the properties of soil type. The results provide a scientific basis for improving SOC estimation accuracy under medium-scale conditions.