Chemical properties of soils submitted to the application of a bioactivator and basalt and serpentinite powders¹

Atributos químicos de solos submetidos à aplicação de bioativo e dos pós de basalto e serpentinito

HIGHLIGHTS:

Basalt and serpentinite powders are complementary alternatives to correctives and mineral fer-tilizers.

Basalt and serpentinite remineralizers must be added at least three months before cultivation for soil acidity correction.

The Penergetic bioactivator accelerates the reaction of remineralizers in the soil.

ABSTRACT

Dependence on external raw materials, the high cost of fertilizers, and the search for more sustainable alternatives have encouraged research with remineralizers. This study aimed to evaluate the effect of adding remineralizers associated or not with a bioactivator on pH, H+Al, Al, P, and K in two soils after four incubation times. A completely randomized experimental design was used in a 5 x 2 x 2 x 2 factorial scheme, as follows: doses of remineralizers (0, 2, 4, 8, and 16 Mg ha^-1), bioactivator (with and without application), type of remineralizer (basalt and serpentinite), and soil class (Oxisol and Entisol), with four replications. The soils were incubated for 30, 90, 120, and 240 days after the treatment applications. The samples were submitted to pH, Al, H+Al, P, and K analyses at the end of each incubation period. The use of increasing doses of remineralizers favored an increase in pH, P, and K and a reduction in Al and H+Al in the studied soils. Serpentinite powder was more efficient in neutralizing soil acidity, while basalt powder was more efficient in providing P and K to soils. The bioactivator reduced the reaction time of the remineralizers and favored the increase in K availability.

Key words:
rock dust; bioactivator; soil incubation time; soil chemical characteristics