Impacts of Agricultural Use on Organic Matter of Histosols in the Cerrado in the north of Minas Gerais State, Brazil

摘要

Despite restrictions imposed by environmental legislation, there is a recurring use of Histosols in Veredas in the Cerrado region, by the farmers in northern Minas Gerais State in southeast Brazil. This hydrophilic environment has low regenerative capacity and is sensitive to human disturbance, and is of great ecological and socio-economic importance (Cunha, 2009).This study analyzed the impacts of agricultural land use by farmers of the rural settlement of San Francisco, Buritizeiro, Minas Gerais, on the organic matter of Histosols. As methodology, we observed the forms of land use and management of these soils through dialogues with farmers, before selecting three representative points for the classification of soils, according to the Soil Taxonomy (USDA, 1999) and the collection of samples at 0-20 cm and 20-40 cm depths. We determined the density of organic matter - DMO (Lynn et al., 1974), organic matter - OM, and the total carbon - Ct (Embrapa, 2006), microbial biomass carbon content -Cbms (Islam and Weil, 1998; Tedesco et al., 1995), and carbon - Corg fractions of soil organic matter (Swift, 1996; Yeomansand Bremner, 1988).