Soil Carbon Content in Areas with Different Land Uses and Vegetation Cover in the Cerrado–Amazon Transition, Mato Grosso, Brazil

The conversion of native forests into agricultural areas without conservation practices can expose tons of soil organic carbon (SOC) to the atmosphere. This study aimed to evaluate the effect of land use and cover (LULC) on C in regions of the Caiabi (SBC) and Renato (SBR) River sub-basins, located in the Brazilian Cerrado–Amazon transition. Data on physical attributes and SOC were obtained by region (upper, middle, and lower), LULC (cropland, pasture, and native forest), and depth (0–10, 10–20, and 20–40 cm), with five replicates for each variable. The highest SOC values were found in areas with higher clay contents or in areas of native forest or crop residues. In the SBC, there was a negative correlation of SOC with sand and particle density (PD) and a positive correlation with silt. In the SBR, there was a positive correlation between SOC and microporosity and total porosity, and a negative correlation with sand, soil bulk density, and PD. The highest SOC values were found in the SBC upper region, in native forest (107 Mg ha−1), cropland (69 Mg ha−1), and pasture (49 Mg ha−1). In the SBR upper region, the values were highest in pasture and cropland (93 and 58 Mg ha−1), and in the lower region, the values were highest in native forest (48 Mg ha−1). SOC varied in relation to the SBC and SBR regions, the LULC, depth, and physical attributes, especially soil texture.