The objective of this work was to evaluate soil compaction induced by tractor traffic in a Red Latosol (Typic Acrustox), submitted to different soil managements. The experiment was arranged in a subdivided parcel scheme, with types of soil tillage as the primary soil treatments and the number of tractor passes as secondary treatments. In addition to a control treatment without soil tillage, the treatments were: tilling to a depth of 18 cm, a tilling to a depth of 18 cm followed by harrow use at a depth of 10 cm, and a 40- cm deep subsoil tilling. After preparing the parcels, soil penetration resistance was measured with an electronic penetrometer, before tractor passes and after 1, 3, 5 and 7 tractor passes on the same track. Soil density was also evaluated. It was concluded that the greater the pulverization during soil tillage, the greater the potential for compaction. Recently tilled soils (plough + harrow) were more susceptible to compaction than soils that were just tilled or deeply tilled. The effect of tractor traffic was chiefly concentrated on a superficial layer. The first tractor pass caused the greatest soil compaction, while the effect of subsequent passes was smaller.
soil physical characteristics; soil tillage system; resistance to penetration
