Resumen
The future of the Amazon Biome depends on the ability of its ecosystems to withstand the perturbations caused by land use and climatic changes. The understanding of how soils functions under different uses is essential to the adoption of alternative systems for a sustainable agricultural. The objective of this study was to comprehend the soil attributes which are most affected by the change of use from forest (F) to pasture (P). The soil data were acquired from the detailed characterization of two toposequences in Eastern Amazonia. The study area is located in Nova Ipixuna (Pará, Brazil) a region with a concentration of agroextractivist settlements. The evaluated attribute were: soil structure type, organic matter content (OM), particle size distribution, bulk density (Bd), cation exchange capacity (CEC), pH and porosity. The exploratory analysis allowed us to better understand the main attributes responsible for the differentiation of soil under P from one under F. The structure type, pH, mesoporosity, CEC and the Bd were the main attributes affected for the land use differentiation. The soil attributes which differentiate forest from pasture can be considered as those most affected by land use changes, confirming the hypothesis of the research. The knowledge acquired may assist in the definition of sustainable production systems in areas of family agriculture.