Organic carbon and carbon stock in soil in different management systems

Abstract

The present study aimed to evaluate the levels of total organic carbon (TOC) and carbon stocks (EstC) in different management systems conducted over time in the municipality of Iguatemi, MS, Brazil. a completely randomized design with four replications, with four areas located on the same rural property being studied, conducted with different management systems, namely: conventional planting, permanent pasture and eucalyptus crops, in addition to the native forest area without anthropic action. Soil collection was carried out in the 0-5, 5-10 and 10-20 cm layers, with the following analyzes: soil density (Ds), TOC levels, with later calculations of the stratification index (SI), EstC and carbon stock variation (EstC), with the forest area as a reference. Subsequently, the variables were grouped in multivariate analysis. All managed areas showed Ds values above the critical limit, higher than the forest area, reaching 1.73 Mg m-3. The forest area obtained higher levels and carbon stocks in all layers, when compared to the managed areas, and these did not present potential for carbon accumulation in the soil, presenting negative EstC in all evaluated layers. All areas studied had an SI greater than 1.00, with the forest area higher than the managed areas, which are similar to each other. The multivariate analysis formed two distinct groups, one containing the forest area and the other containing the management systems.