Investigation of Forest Soil Disturbance Caused by Rubber-tired Skidder Traffic

Abstract

Soil compaction and rutting from ground skidding is a common consequence of soil disturbance on skid trails. In this research
the superficial transformation and degree of soil compaction caused by rubber-tired skidders Taf E655 was investigated in Patom
district, hyrcanan forests, IR-Iran. To measuring superficial transformation of soil, skid trail cross profiles were taken in every 10
meter and changes were recorded after skidder passes. Rut depths were measured with the leveling instruments and ruler. The
field method and sand bottle cylinder were used to estimation of soil bulk density. Results showed that the rut depth developed
with increasing of skidder traffic. Also, at the center of skid trail (140-260cm) little change of depth with traffic was observed.
While at the edge of the skid trails the rut was deeper than the center. Skidder traffic significantly increased the soil bulk density.
The maximum increase in soil bulk density was occurred in 18th pass (1.62 gr cm-3). Beyond 18th pass, there was no significant
increase in bulk density. The forest soil compaction and rutting problems can be reduced by restricting the amount of ground area
covered by skid trails, using of tire pressure-control systems and choice of best machine with respect to environmental impact and
productivity.