SPATIAL VARIABILITY OF SOIL ATTRIBUTES IN AN AREA UNDER NO-TILLAGE SOYBEAN AND CORN CULTIVATION

Abstract

The use of tools such as mapping the spatial variability of soil attributes makes it possible to rationalize management and promote sustainable agriculture, in addition to gains in production. The objective of this work was to perform a detailed analysis of the physical and chemical properties of the soil in a study area located in the municipality of Itapaci - GO. A sampling grid with 50 points spaced at 100 m was used, 44 points in the established grid and 6 points randomly. The cone index (IC) was sampled at depths of 0.00-0.10 m, 0.10-0.20 m, 0.20-0.30 m and 0.30-0.40 m, and samples of silt, clay, sand, organic matter and pH were sampled at 0.00-0.20 m, 0.20-0.40 m, with the points georeferenced with a GNSS receiver. The data were submitted to geostatistical analysis in the QGIS program with the Smart-Map plugin. The adoption of a 1 ha sampling grid with random points was effective in determining spatial dependence and mapping the studied variables. The IC values were high, exceeding 2 MPa, which may limit root development. The soil organic matter content (between 15 and 20 g kg^-1) was considered adequate for cultivation, promoting a healthy production system. The slightly acidic pH and clayey texture benefit nutrient retention and support capacity for crops, and it is important to monitor these parameters regularly to ensure optimal conditions for agricultural production.