Elevation and total nitrogen are the critical factors that control the spatial distribution of soil organic carbon content in the shrubland on the Bashang Plateau, China

[Display omitted] •SOC content of shrubland is closely related to elevation and total nitrogen.•Elevation affects shrubland SOC content through both direct and indirect pathways.•Total nitrogen has the greatest total and direct effect on the shrubland SOC content. Shrubland has been identified as the most uncertain factor in the C sink in China, but little detail is available regarding the soil organic carbon (SOC) of this significant biome. The effects of influencing factors on the spatial distribution of SOC content have been extensively investigated, but whether these factors reflect a ‘direct’ or ‘indirect’ effect is not clear. In this study, 93 topsoil plots were surveyed to measure the SOC content and the influencing factors, including topography (elevation (Ele), slope gradient (SG), and aspect (SA)), soil conditions (pH, bulk density (BD), soil total porosity (STP), soil water content (SWC), soil temperature (ST), soil salinity (SS), total nitrogen (TN), total phosphorus (TP), and available potassium (AK)), and vegetation (aboveground biomass (AGB)) on the Bashang Plateau in China. The results indicated that the SOC content varied moderately across the entire catchment and was closely related to Ele and all soil conditions (P