Spatial distribution of soil chemical properties in the cerrado of Tocantins

Abstract

Information on spatial variability of soil chemical properties is allowing an increasingly efficient management of soil fertility. This study was conducted in the municipality of Santa Rosa do Tocantins, TO, in the 2018/2019 crop year. The objectives of the study were to characterize the spatial variability of chemical properties of a dystrophic Red Latosol in the Cerrado of Tocantins using geostatistics and optimize the management of soil fertility by means of precision agronomy techniques, for more efficient input use in agricultural production areas. For the experiment, 49 soil samples were collected at 0.2 m depth, from equidistant points in a regular grid 100 m apart, over an area of ??150 ha. Each sample was composed of 5 subsamples. The soil properties evaluated included pH, bases sum, potential acidity, organic matter, total cation exchange capacity, base saturation, phosphorus, sulfur, potassium, calcium, magnesium, boron, copper, iron, manganese, and zinc. A descriptive analysis was carried out, highlighting the mean, median, minimum, and maximum values for each soil variable. In addition, the coefficients of variation, asymmetry, kurtosis, and the normality test of Kolmogorov-Smirnov were performed. The area presented significant variations in chemical and macronutrient attributes and little variation in micronutrients, except for zinc. The study reveals variations in different soil attributes and the need for correction depending on the requirements of the crop.