SPATIAL DISTRIBUTION OF SOIL CHEMICAL ATTRIBUTES IN AREAS UNDER DIFFERENT AGRARIAN USES - DOI: 10.13083/1414-3984.v22n05a06

Abstract

Knowledge on spatial variation of soil properties can help to identify the effects of use and management applied to soil over time. In this sense it was sought to study the chemical characteristics of typic quartzipsamment soil submitted to five different types of use. The experiment was conducted in October 2010, in the municipality of Araguaína – TO, characterized as belonging to the Amazon biome. We studied the spatial variability of the following soil chemical properties: pH, P, K+, Ca2+, Mg2+, Al3+ and organic matter (MO). The area assessed included five different land uses (sugarcane plantation, pasture with poultry in alluvial areas, irrigated pasture and conventional pasture, native forest), all being related. Chemical variables were obtained in regular grids of 50 x 50 m, at two depths, 0-10 cm and 10-20 cm, totaling 110 soil samples. It was observed that the chemical properties are influenced by the soil use. Areas of irrigated pasture and sugarcane showed a great capacity for nutrient extraction by these types of use. Poultry production in alluvial areas tends to show chemical properties similar to native forest, highlighting the natural recovery. The grid of 50 by 50 m used for sampling of soil chemical characteristics is sufficient to show spatial distribution the chemical properties pH, K+, Ca2+, Mg2+, Al3+, and MO, but it is not sufficient to present spatial distribution of P, indicating the need for a smaller sampling grids for its detection.