Physical recovery of an Oxisol under an integrated crop-livestock system in southern Brazil

Soil management could help the recovery from a soil compaction. We investigated the impact of a 14-year integrated soybean-beef cattle system on soil physical recovery. Soil core samples were taken from 0-5 and 5-10 cm twice after grazing and soybean harvesting. Soil compaction and soil recovery capacity were determined in the laboratory by compression of field core samples following wetting-drying cycles. Soil bulk density and macroporosity were measured six times, i.e. before and after the soil compression, and after each wetting-drying cycle (four times). Soil organic carbon and texture were determined. Intensive grazing increased soil bulk density compared to moderate and light (from 1.38 Mg m(-3) to 1.24 Mg m(-3)) and decreased macroporosity (from 0.09 m(3) m(-3) to 0.14 m(3) m(-3)) at the 0-5 cm layer. The wetting-drying cycles reduced soil compaction in all treatments, especially in the lower grazing intensity and ungrazed (macroporosity from 0.08 m(3) m(-3) after compaction to 0.16 m(3) m(-3) after recovery). Our data suggest that the soil physical recovery depends on its initial physical conditions. Soil recovery responses to stresses observed, positive in moderate grazing, suggest that measurements of physical recovery could be useful in describing differences between integrated soybean-beef cattle systems.