Soil chemical and physical attributes of an inceptisol under different land uses, in the Zona Da MA TA of Minas Gerais State, Brazil

Knowledge on chemical and physical soil features in mountainous areas is very important for sustainable planning of natural resources. Thus, this study aimed to determine the soil chemical and physical attributes of an Inceptisol under different land uses, in Visconde do Rio Branco, in the Zona da Mata of Minas Gerais state. Five land uses were evaluated: orange, rubber tree, sugar-cane, pasture and forestry. Rubber tree, orange and pasture were cultivated during 15 years, and sugar-cane for 1.5 years. Prior to these uses the area had been cultivated with sugarcane for about a century. Sampling was carried out in three replicates (soil pits) at depths of 0-20 and 20-40 cm. The following chemical attributes were determined: soil organic matter (MOS); pH in H2O, P, Ca2+, Mg2+, K+, A1(3+), H+Al, SB, CEC(t), CEC pH 7.0 (T), BS, aluminum saturation (m), P-rem. The following physical attributes were measured: texture, bulk density, particle density, porosity, water retention curve, soil penetration resistance and agkregate stability, as well as the ratios of available water / total porosity and field capacity/total porosity. Results showed that the soil fertility is low and exchangeable Al3+ very high under all land uses, apart from sugarcane, with medium values of soil fertility and negligible levels of exchangeable aluminum. The agricultural use decreased MOS. Land uses with rubber tree and sugarcane improved the soil physical properties to values comparable with the native site. On the other hand, in areas under orange and pasture the soil bulk density and resistance increased compared to the other land uses, while the aggregate stability and porosity decreased.