Soil quality indicators for Urochloa brizantha fertilized with wood ash ¹

Indicadores de qualidade do solo sob cultivo de Urochloa brizantha adubada com cinza de madeira

HIGHLIGHTS:

The use of wood ash increased P and K concentrations in the soil and activity of the acid phosphatase enzyme.

The management of wood ash incorporation is directly linked to soil density.

Wood ash reduced soil bulk density by up to 9.66%, favoring root growth.

ABSTRACT

The objective was to evaluate the effect of wood ash dose and application management on soil quality attributes in a Cerrado area cultivated with Urochloa brizantha. The experiment was carried out in a randomized block design in a 5 × 2 strip-plot scheme and four repetitions. The ash doses were 0, 8, 16, 24, and 32 t ha^-1, and the application management considered wood ash that is incorporated and not incorporated into the soil. The P, K, and pH values of the soil increased with an increase in the doses of wood ash. The soil bulk density decreased by 9.66% with the wood ash doses of 24 and 32 t ha^-1 incorporated into the soil. Owing to an increase in the soil pH, a wood ash dose of greater than 16 t ha^-1 decreased the enzymatic activity. A wood ash dose of 24 t ha^-1 resulted in better conditions for the soil, improving its quality and contributing to the balance and dynamics between the chemical, physical, and biological attributes of the soil, which led to the reduced density and greater availability of P in the soil.

Key words:
ash management; phosphatase enzyme; soil improvers; paiaguás grass