Abstract:In this paper, the main objective was to better understand the spatial distribution characteristics of soil organic carbon (SOC) and labile organic carbon (LOC) on the sloping farmland. Soil samples were collected from different geomorphic positions at the Suining site, which was a typical purple soil hilly region. Content and storage of SOC and LOC were studied. The results showed that soil depth was only 22.3 cm in the upper position. Compared with the soil depth in the upper position, it was almost 2.01 times in the middle position and 3.30 times in the lower position. Soil bulk density in the middle and lower position was 12.12% and 2.42% lower than in the upper position, but soil porosity in the middle and lower position was 19.82% and 3383% higher than in the upper position, respectively. Storages of SOC and LOC significantly increased from the upper position to the lower position. Compared with the upper and middle positions, SOC storage in the lower position was 674.74% and 104.09% higher, LOC storage was 958.51% and 267.75% higher, respectively. Contents of SOC and LOC in different positions of the sloping farmland decreased with the increasing soil depth. The depth distribution of SOC and LOC for the middle and lower positions could be described by the formula [Y = aln(X) + b], but it did not follow this formula for the upper position. There was a significant positive correlation between SOC and LOC in the sloping farmland. Therefore, the spatial distribution pattern of SOC and LOC were affected by soil erosion in the sloping farmland.