Efeito residual do pó de basalto nos atributos químicos do solo

Abstract

Fertilizers are essential for the production chain, however, Brazil is highly dependent on countries that export raw materials for domestic supply. Therefore, alternatives to minimize this dependence on Brazilian agriculture are necessary. Currently, Brazil is the fifth largest consumer of NPK in the world, being dependent on the foreign market. Thus, soil remineralizers are an option to complement chemical fertilization and reduce external dependence. This is because its source material is natural and a source of various nutrients for plants, in addition to enabling the structuring of more stable soils for agricultural production. Therefore, the objective was to evaluate the residual effect of doses of basalt powder on the chemical attributes of the soil, after growing corn second crop, in 2021. The experiment was carried out in an experimental area of the Federal University of Grande Dourados (UFGD), in the municipality of Dourados, MS. The local soil was classified as Distroferric Red Latosol. The experimental design was randomized blocks, with three replications. The treatments consisted of five doses of rock dust (0, 2.5, 5.0, 7.5 and 10 Mg ha-1) manually applied to the surface, without incorporation, 30 days before soybean sowing, in the harvest from 2017/18. After corn harvesting, a soil sample was collected for further chemical analysis. Two samples were collected in the line and four samples between the lines, in different places in the useful plot, stratifying the layers of 0-10 and 10-20 m deep, forming a sample composed by plot, for each soil layer. The soil was taken to the soil laboratory of the Faculty of Agricultural Sciences, passed through a 2.0 mm sieve and dried in the air. The following were analyzed: pH in water, pH CaCl2, M.O, Ca, Mg, K, P Melich-1, Al, H+Al, Cu, Fe, Mn and Zn. The data collected from the different measured variables were used in analysis of variance (ANOVA), by the F test. The residual of the basaltic rock dust influenced the pH in CaCl2, pH in water, iron, copper and Ca/Mg ratio for the layer of 0-10 cm, with a linear increase in pH values and Fe and Cu contents as a function of basalt powder doses. For the 10-20 cm layer, there was an influence on pH in CaCl2 and pH in H2O, with a linear increase in pH values depending on the doses of basalt powder Basalt powder has potential for use in agriculture, mainly due to its properties of providing micronutrients to the soil and its alkalizing power.