Variabilidade espacial e correlação de micronutrientes catiônicos do solo e NDRE da soja

Abstract

The spatial analysis of chemical attributes of the soil allows the monitoring of their variability over time, serving as information for the management of fertility at levels satisfactory to agricultural crops. As a result, interventions are usually carried out in a localized manner through the application of inputs at a variable rate. Therefore, the objective was to evaluate the spatial variability and availability of soil micronutrients and pH throughout the area, using the 2018/19 soybean crop as a criterion. The experiment was conducted in an area of approximately 100 ha located in the municipality of Maracajú, MS, during the 2018/2019 corn harvest. Soil correction was carried out by applying a variable rate of calcitic and magnesium limestone, followed by incorporation of these by a plow harrow. Subsequently, georeferenced samplings were carried out in a grid with regular spacing for soil collection. 50 sample points were allocated, with a 2 ha grid, collecting 12 sub-samples per point in the 0.00-0.20 m layer, for pH determination in CaCl2, Fe, Cu, Mn and Zn. A classic descriptive analysis and a normality test of the data were performed. Finally, spatialization maps were made using the Ordinary Kriging method. There was a predominance of Fe, Cu, Mn and Zn contents in the soil, with a predominance of them throughout the area, while in the same there is a predominance of medium contents for pH throughout the area. Zn and Fe showed greater spatial variability and RENDI showed uniformity in the production unit, pointing to a normal development of the soybean crop.