Variabilidade espacial de atributos químicos e físicos do solo, e da produtividade de culturas

Abstract

Knowing the spatial variability of soil chemical and physical attributes is important for the management of crops of agronomic importance such as soybean and corn. The objective of this study was to investigate the Spatial analysis, by means of geostatistical analysis techniques of soil chemical and physical attributes (texture and resistance to penetration), and characterize units of differentiated management according to the thematic maps interpolated by ordinary kriging and indicative kriging. The work was carried out in a commercial field with succession of the soybean and corn crops, sown in the 0.45 m spacing under Distroferric Red Latosol, in a plot of 126 ha, located in the municipality of Dourados-MS. The data were collected at 126 points separated by 100 m from each other for soil chemical attributes and 60 points for soil granulometry. The composite samples were composed of eight (8) sub-samples randomly taken around each sampling point, in the layers 0.0-0.10 and 0.10-0.20 m for the evaluation of soil chemical attributes and granulometry. Sampling for the study of soil resistance to penetration was performed with an electronic penetrometer at 126 points to a depth of 0.40 m. According to the maps, the chemical attributes were found with indices considered high for Ca, Mg, P and K. It was observed that most of the area presents resistance to penetration between 2 and 4 MPa, which demonstrates that there is no need To perform a process of soil revolving, however in case it needs, the layers to be revolved will be at the intermediate depths. The productivity maps show points of the area with low productivity, as well as points in the border of the area, and by climatic factors directly influence the productivity, however its production throughout the seasons was satisfactory.