نوع مقاله : علمی - پژوهشی
1 استادیار، گروه کشاورزی، دانشگاه آزاد اسلامی واحد خلخال، خلخال، ایران.
2 دانشیار، گروه جنگلداری، دانشکدۀ منابع طبیعی، دانشگاه گیلان، صومعه سرا، ایران.
عنوان مقاله [English]
One of problems in managing of uneven-age forests is logging damages to residual trees and reducing stand quality and quantity in years after logging operation. In this research, trend of bole decay and economic loses by it, following logging damages, were analyzed at a 10 year period in a mixed beech forest in Guilan province. Volume of decayed section on trees bole was measured by Smalian formula, and volume of standing trees bole was estimated by local tree volume tables via plots of 0.1 ha area and systematic sampling design at the start and end of period. Results showed that volume of decayed bole were increased from 0.48 m3/ha at the start of period to 1.71 m3/ha at the end of period (P < 0.01). Ratio of decayed-bole volume to standing tree volume were increased from 0.24% at the start of period to 0.81% at the end of period (P < 0.01). The volume trend of decay was estimated 0.123 m3/ha/yr and the economic trend of decay was estimated 1.25 mil. Rial/ha/yr. The decay volume at the end of period was more than the start of period in the all tree species (P < 0.01). The volume trend of decay was increased by increasing of trees DBH. In order to reduction of trees-bole decay, logging damages should be reduced, that this issue needs to careful and principles planning of each logging stage, education and reeducation of logging personnel, and continuous assessment of logging damages.