Soil compaction induced by careful logging in the claybelt region of northwestern Quebec (Canada)

Abstract

Soil compaction induced by forest harvesting operations can reduce site productivity. Intensity, extent and persistence of soil compaction were assessed on fine- to medium- and coarse-textured soils. Severe compaction took place in the wheel track section of the skid trails. On fine- to medium-textured soils, half of the effects on the 0- to 10-cm and 10- to 20-cm mineral soil bulk densities (+11 and +8%) and half of the changes in the 10-cm depth soil strength (+69%) occurred in the course of the first two skidding cycles (cycle of half impact). On coarse soils, half of the effect on the 0- to 10-cm bulk density (+11%) occurred during the first three passes. Cycles of half impact for soil strength were 9, 14, 7 and 6 for the 2.5-, 5-, 10-, and 20-cm depths and corresponded to increases of 235, 402, 157 and 103% respectively. Compaction was more limited between track sections of trails. Six to twelve years following clearcutting on fine- to medium-textured soils, 0- to 10-cm soil bulk density was less in the skid trails than on the undisturbed sections of cutovers. Careful logging on moist, fine- to medium-textured soils is the safest way to limit the extent of soil compaction. On coarse-textured soils, spreading the traffic remains a valid option. Key words: Soil compaction, bulk density, soil strength, forest harvesting, careful logging