SOIL CARBON STOCK IN DIFFERENT USES IN THE SOUTHERN CONE OF MATO GROSSO DO SUL

Abstract

This study aimed to assess the soil density (Sd) and the total organic carbon contents and stocks in different management systems and implementation times in the municipality of Iguatemi, MS, Brazil. A completely randomized design with four replications was applied to four areas: conventional tillage (CT), reformed pasture (RP), and degraded pasture (DP), in addition to a native forest (NF) area with no anthropic action. Disturbed and undisturbed soil samples were collected at depths of 0–0.05, 0.05–0.1, and 0.1–0.2 m. The determination of Sd and total organic carbon content (TOC) allowed calculating the carbon stock (Cstock), the stratification index (SI), and the carbon stock variation (ΔCstock), with subsequent multivariate analysis. The NF area presented the highest TOC contents at all depths compared to the managed areas, with a value of 17.45 g kg−1 at a depth of 0–0.05 m. The RP and NF areas showed similar SI, which was higher in PD, with a value of 2.54. Except for RP, the other managed areas showed a negative ΔCstock in the soil profile relative to the NF area. The RP and NF areas promoted the maintenance of TOC in the soil, while DP and CT compromised the edaphic quality.