Soil organic carbon in no-tillage systems of different ages in Southwest Mato Grosso, Brazil

Abstract

The objectives of this study were to evaluate the effect of the no-tillage system on soil bulk density, soil organic carbon, and carbon stocks in Plinthic subgroups and Oxisols, located in Pontes and Lacerda, State of Mato Grosso, Brazil. The treatments were native vegetation and no-tillage systems established for 3, 8, 10, and 12 years. To analyse soil organic carbon, soils were sampled in each area, with three repetitions, at layers of 0-0.05; 0.05-0.10; 0.10-0.20; 0.20-0.40; 0.40-0.60; 0.60-1.00; 1.00-1.50 and 1.50-2.00 m. For soil bulk density, undisturbed samples were collected at layers of 0-0.20 and 0.20-0.40 m. Compared with areas of native vegetation, soil bulk density values after 12 years increased by 25% in Oxisols and 30% in the Plinthic subgroups. In Oxisols and Plinthic subgroups, respectively, organic carbon concentration was, on average, 20.57, 25.04 g kg-1 under native vegetation; 16.82, 16.59 g kg-1 after 3 years of no-tillage; 13.31, 4.96 g kg-1 after 8 years; 16.52, 14.39 g kg-1 after 10 years; and 17.97, 18.53 g kg-1 after 12 years. In both soils, the no-tillage system contributed to an increase in carbon stocks over the years, but not at depth, being generally limited to the top 0.20 m of the soils. Compared to native vegetation, after 12 years of no-tillage, carbon stocks decreased at a rate of 0.075 Mg ha-1 year-1 in the Plinthic subgroups and increased by 2.3 Mg ha-1 year-1 in Oxisols.

Atributos físicos, químicos e caracterização morfológica de solos na cidade de Cáceres - Mato Grosso

“…Em Mato Grosso, estudos com distintas perspectivas, mas que tem em comum o estudo dos solos, tem sido desenvolvido (Padilha et al, 2020;Oliveira et al, 2020;Oliveira et al, 2021;Severino et al, 2021;Silva et al, 2022). Oliveira et al (2022) analisaram as contribuições dos componentes ambientais para o Pantanal mato-grossense.…”