Soil organic carbon (SOC) is the largest terrestrial organic carbon pool; thus, there is a growing interest in its spatial distribution and potential for carbon sequestration. However, our knowledge about spatial distribution in different soil depths and under different land uses is still limited in many regions of the world. The aim of this study was to analyse the soil depth and land use specific SOC contents in a small catchment (6.46 km²) located in the tropical monsoon climate of South India and to determine potential auxiliary variables suitable to derive high resolution maps. A soil survey was carried out, taking 112 soil cores representing three soil depth increments each (< 0.2 m, 0.2 - 0.5 m, and 0.5 - 0.9 m, respectively) and a number of spatially distributed auxiliary variables (slope; curvature; elevation above the next potential irrigation source; water erosion; wetness index; mean NDVI) were determined. The interrelationship between SOC contents and these variables and their principal components were analysed with a combination of an ANCOVA, an iterative linear regression and a multivariate non-linear regression procedure. The mean SOC contents of 3.4 g kg-1 (upper 0.9 m) are consistent with large scale data. The more detailed analysis of land use specific differences in SOC contents showed that the sampling points of irrigated arable land had the highest mean contents in topsoil and over the whole measured depth. SOC contents under arable land were followed by those under plantations, forests/shrubland and grassland. Within the different land use categories SOC under arable land declines with increasing elevation above the next potential irrigation source, SOC under grassland is positively correlated with mean NDVI, and SOC under forest/shrubland is best described by variables indirectly related to the accessibility of forest areas. Overall, this study indicates that the commonly used relations to estimate spatial distribution of SOC on larger scales might not be adequate for large areas in South India, which are dominated by pronounced dry and wet seasons, intensive irrigation farming and human-induced forest degradation.