Forest residuals layer in the preconsolidation pressure of two Oxisols

Abstract

The objective of this work was to evaluate the effect of forest residue on the preconsolidation pressure using the load support capacity models of a Typic Haplustox and aTypic Acrustox. Twenty undisturbed soil samples were collected in each soil type at 10–13 cm depth, in the traffic line of the forwarder after it trafficked over residue disposition, two and eight times, in three conditions, being the traffic performed: on brushwood (G); on the brushwood and bark (GC); on soil without residue (SR); and on soil with no traffic (ST). Undisturbed soil samples were used in the uniaxial compression tests. The particle size distribution, organic matter and particle density were also determined. The traffic over forest residues attenuated the soil compaction in the studied soils, mainly in the condition of brushwood and bark (GC); soil without residue (SR) was the worse condition in the two soil types. As traffic intensity increased from two to eight times, a larger soil compaction ocurred.