Levels of induced pressure and compaction as caused by forest harvesting operations

this study aimed to determine levels of pressure and compaction induced by forest harvesting operations in a red latosol (lv) under planted eucalyptus. undisturbed soil samples were collected from layers 0-3 and 15-18 cm and then used in a uniaxial compression test. sampling was done before and after harvesting operations. equipment being evaluated included: harvester, feller buncher, forwarder, self-loading adapted tractor, standard truck, wide-tire truck and grapple saw. average pressures induced by the grapple saw were 320 kpa and 272 kpa, causing compaction in 80% and 20% of samples respectively from layers 0-3 cm and 15-18 cm, which indicates substantial degradation of soil structure in areas where timber is processed. in layer 0-3 cm, average pressures induced by the harvester and by the feller buncher were 240 kpa and 263 kpa respectively, while in layer 15-18 cm pressures were 234 kpa and 239 kpa respectively. the feller buncher caused higher soil compaction than the harvester in layer 0-3 cm, yet in layer 15-18 cm they had similar behavior. all timber forwarding equipment led to soil compaction. the wide-tire truck was the forwarding implement promoting the highest rate of compaction, in both residue conditions. traffic intensity 7 promoted the highest rate of soil compaction.