IMPACTS OF MECHANIZED WOOD HARVESTING IN CHESTNUT COPPICES: A CASE STUDY

Abstract

The authors carried out a survey to identify the damages produced by the improper use of an advanced mechanization in the final cut of chestnut coppices, assessing the incidence that this practice can have on forest ecosystem and coppice sustainability. This study took place in two yard of Central Apennines, in the final cut of a chestnut coppice, the damages were recorded in felling performed by crawler excavator with harvester head, in felling with chainsaw and in skidding performed by excavator with grapple cranes. A detailed survey of damages was conducted on stumps and on the residual trees. The evaluation of damages considered also soil compaction. From data analysis resulted a large damage in residual stand, particularly where the operations of felling were performed using the excavator with harvester head. A large damage spread on stumps was caused by tracks of felling and skidding machines. In the area where the felling operation was performed with chainsaw resulted a reduction of damaged stumps, the percentage of damages was sensitively reduced. The residual trees were damaged particularly on stems, the damage was high in both the felling methodologies, mainly caused by a non directed felling and by the movement of felled trees. In the excavator area was noticed a wide soil compaction on the whole surface, with a sensitive bulk density increase, both on main and secondary forest roads. The study results shows that in order to use an advanced mechanization in these forests a suitable network of strip roads is indispensable, allowing damages only on roads and their edges, reducing damages extension on the whole residual stand. Moreover impacts on soil and residual stand is reduced with the necessary operators training, the use of proper working techniques and choice of the best machines in each operational context.