Assessing the damaged regeneration by mechanized and traditional loggings in the forest (Case study: Lala forest of Mazandaran Wood and Paper Company)

Ecologically and economically sound forest logging is regarded as a biological and practical necessity. However, the logging activities cause damages to forest, in particular to its regeneration. Both traditional and in mechanical wood harvesting and transportation are practiced in Caspian forests. Here, the damages to the regeneration raised by skidding with mule (traditional) and Skidder (mechanized) were assessed and also compared. This study was conducted in Parcel 4 of Lala series of Mazandaran Wood and Paper Company forests. The applied forestry regime is single tree selection. Random systematic sampling was used with circular sample plots to study the regeneration damages for the two methods, measured before and after skidding. The results showed that 2.38 % of the regeneration was damaged during the tree felling and conversion operations, whereas 8.56% was damaged after the skidding operations. In this study, the industrial skidding damages to groups of seedling, small sapling and sapling were assessed to account for 10.67%, 7.46% and 1.78%, respectively. Furthermore, the traditional skidding damages to groups of seedling, small sapling and sapling were 9.2%, 9.11% and 6.58%, respectively. Also the total damages to regeneration in the industrial skidding were assessed to be 7.93%, whereas the rate was 9% in traditional skidding. Finally, the statistical analysis showed that the damages caused by traditional and industrial skidding are not significantly different between the two studied parts of the forest parcel.