Correlação espacial entre a condutividade elétrica e atributos químicos e físicos do solo

Abstract

Precision agriculture is a set of techniques and technological resources to support the management of agricultural production systems, with the objectives of maximizing economic results and optimizing natural resources while preserving the environment. Theelectrical conductivity enters this context, together with the geostatistics, facilitating and reducing the costs of soil sampling. The objectives of this work were: I) To determine the variability of the chemical and physical attributes and the electrical conductivity of the soil measured by direct contact sensor. II) To determine the linear and spatial correlations of the chemical and physical attributes of the soil with the electrical conductivity. III) Perform the kriging of the attributes of the soil and electrical conductivity, as well as the cokrigagem of the attributes of the soil as a function of the electrical conductivity. The experiment was conducted at Ribeiro do Céu farm, located in the municipality of Nova Mutum. The soil of the site is classified as Dystrophic Red-Yellow Latosol, with a sandy clay loam texture. For this, a rectangular mesh was installed with 46 sampling points distributed over an area of 226 hectares, in which the physical and chemical attributes of the soil in the 0-0.20 m and CE layer were determined in the layers 0-0.30 m (CE30) and 0.30-0.90 m (CE90). The electrical conductivity was measured using the Veris 3100® sensor, and was georeferenced with the aid of a GNSS receiver. The Red-Yellow Dystrophic Latosol presents high variability of the physical, chemical and EC attributes, since the coefficients of variation of soil and EC attributes were higher than 15%. The levels of sand, clay and organic matter presented the best correlation with EC. The cokrigagem of the attributes of the soil according to the EC presented greater efficiency in the prediction of physical and chemical attributes of the soil.