Variabilidade espacial de atributos químicos do solo

Abstract

The reconciliation of spatially distributed data in the agricultural area through its analyzes is an important diagnostic tool for a more efficient use of information, allowing a better management of variability in the field. The objective of this work was to study, through geostatistics, the spatial variability of chemical attributes of the soil after the harvest of the corn crop. The research was developed at Fazenda Água Boa located in the municipality of Antônio João / MS. Soil data were collected according to a mesh of 153 sample points spaced 70 m in a 0-20 m layer. After laboratory analysis the data were explored in the GS + ® program. The following PH variables CaCl2, PH H2O, P and K were determined; Ca, Mg and Al, H + Al. Base saturation (V%), CTCtotal (T) and base sum (SB) were calculated. The data were evaluated by descriptive statistics and spatial dependence analysis, based on semivariograms adjustment, interpolation of data by kriging and construction of isoline maps. Most of the attributes presented a mean coefficient of variation (CV), the highest one found for Al, 96.75%, and the lowest for pH CaCl2, pH H2O. The great majority of the evaluated attributes showed spatial dependence, which was classified as moderate and strong. Most of the data conformed to the semivariogram of the Spherical model, followed by the Gaussian and exponential.