Soil tillage, machine traffic and animal trampling in unsuitable wet soil conditions (consistency in the plastic state) cause plastic and non-recoverable deformations in the soil. The aim of this study was to determine and evaluate the soil physical and mechanical properties to characterize the level of soil compaction and load bearing capacity in three areas with different land uses (rotational grazing, native forest and conventional tillage). Undisturbed soil samples were collected in layers from 0.00-0.05, 0.05-0.10 and 0.10-0.15 m, with five replications. The different land uses altered soil bulk density (from 0.84 Mg m-3 in the native forest to 1.48 Mg m-3 in rotational grazing), preconsolidation pressure (from 16.5 kPa in conventional tillage to 79.4 kPa in rotational grazing), compression index (from 0.14 in rotational grazing to 0.77 in native forest), resistance to penetration (from 0.45 MPa in conventional tillage to 2.56 MPa in rotational grazing) and macroporosity (from 0.35 m³ m-3 in native forest to 0.03 m³ m-3 in rotational grazing). Animal trampling in an intensive grazing area alters soil structure up to levels of compaction restrictive for plants. Native forest and conventional tillage are most susceptible to soil compaction due to their high compression index and low preconsolidation pressure and bulk density.
native forest; penetration resistance; soil bulk density; preconsolidation pressure
