SMOOTHER TERRAIN-MACHINE Progress report from an R D-project

摘要

Damages by terrain-vehicles on the ground and growing trees is a problem of increasing importance in forest operations, primarily in thinnings. These damages cause considerable loss of volume and quality yield in subsequent harvesting operations. The importance of this problem is expected to increase for several reasons. One is the continously increasing area of thinning stands due to an uneven age distribution of Swedish forests. Another reason is the development towards logging systems where tops, branches etc. are utilized for energy purposes. Under such conditions the slash will not be available as a ground cover, protecting the soil for compaction and root systems for damages. Access to terrain-machines, less liable to damaging the stand, is therefore a crucial prerequisite for the successful development of future thinning systems. The knowledge of how to design less damaging terrain vehicles is, however, very limited. A research project Smoother terrain-machine' was first out-lined at SLU in 1978 in order to fill this gap of basic knowledge. Following a few years of pilot studies, evaluation of alternative research approaches and development of measuring techniques, the project is now in a productive phase.