Soil Organic Matter and Microbial Biomass Under Cultivation of Urochloa Brizantha Fertilized with Wood Ash in the Cerrado of Mato Grosso

ABSTRACT

The use of waste such as wood ash as an alternative fertilizer in agricultural production can result in an improvement in the chemical and biological characteristics of the soil. The objective of this research was to evaluate the effect of doses and management of wood ash application in the organic matter content and biological attributes of the soil in a Cerrado area cultivated with Urochloa brizantha cv BRS paiaguás. The experiment was performed in randomized blocks, in a 5 × 2 striped scheme, with five doses of wood ash (0, 8, 16, 24 and 32 t ha⁻¹) and two application managements (with and without incorporation to the soil) with four repetitions. The variables analyzed were: soil organic matter content, microbial biomass carbon, basal respiration, qCO₂ and β-glucosidase activity. During the evaluations it was observed a reduction of 0.36 g kg⁻¹ of organic matter for each ton of ash applied to the soil, regardless of management. This reduction also occurred in microbial biomass carbon and β-glucosidase activity. initially the ash doses elevated the soil respiration and the metabolic quotient, evidencing a small stress in the soil microbiota, however, in the last evaluation the rates of these two variables remained stable. The application of wood ash, in doses ranging from 16 to 24 t ha⁻¹, can be used as soil conditioner and fertilizer in pastures, because it results in better conditions for the soil.

KEYWORDS:

• Basal respiration
• paiaguás grass
• pasture maintenance
• soil enzyme
• soil quality

Acknowledgements

Thanks to CAPES (Coordination for the Improvement of Higher Education Personnel) for supporting research. To GPAS (Group of Practices on Water and Soil) of the Federal University of Rondonópolis, for the assistance in the execution of field and laboratory activities.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The work was supported by the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES).