Homegardens are considered as an alternative to preserve and/or restore the fertility and productivity of degraded soils. The assessment of changes in soil chemical properties resulting from land use and management is important to understand these changes and allow a rational intervention to ensure production on a sustainable basis. Thus, the aim of this study was to evaluate the soil chemical properties of homegardens and other systems of land use, as well as to identify the factors that influence fertility in areas of family farming in the municipality of Bonito, Eastern Amazon. Three soil samples were collected from secondary forest, cassava (Manihot esculenta) monoculture, silvopastoral systems and homegardens, from the depth range of 0-20 cm, and were evaluated in a completely randomized design with 12 treatments and three replications. The data were subjected to analysis of variance with the Kruskal-Wallis test, correlation analysis and principal component analysis. The variables studied, except Mg and Ca, were influenced by the soil cover. The homegardens, agricultural monoculture and silvopastoral systems were similar to the secondary forest in terms of nutrient cycling, with the exception of one 35-year-old homegarden, where the levels of P and K were higher. The soil fertility was explained by three factors: soil nutrients and salinity (P, K and Na); soil acidity and aluminum toxicity (Ca, Al, Mg, and pH); and by soil organic matter (SOM).
Key words: Soil cover, agroforestry systems, tropical soils, family agriculture, Amazon region.