Chemical Attributes of an Oxisol Under Different Agricultural Uses in the Brazilian Semiarid Region

Different soil managements evidence soil properties, contributing positively or negatively to its quality. A study was conducted in the city of Martins, Rio Grande do Norte (RN) state, in four cultivated areas- corn intercropped with beans (CICB), cassava monocrop (CAMO), bean monocrop (BEMO) and native forest (NF, considered as the original soil condition). This study aimed to evaluate changes in the chemical properties of an Oxisol in function of different agricultural uses (N, P, K+, Ca2+, Mg2+, Na1+, Al3+, pH, EC, H+Al, BS, V, CEC, t, m, OM and ESP) and the distinction of environments using multivariate analysis. The sampling was performed up to 30 cm deep. Soil pH values were kept close to 5.5, except for the area with corn intercropped with beans, whose values were higher than 7.0. Corn intercropped with beans had the highest concentrations of K+, Na+ and Ca2+ on the soil, with a direct impact on base sum. Different uses modified soil chemical properties. Corn intercropped with beans differs from the other treatments due to the addition of solid waste to the soil. Principal component analyses showed pH and exchangeable bases are the most sensitive indicators of environment separation.