نوع مقاله : مقاله پژوهشی
1 استادیار گروه جنگلداری، دانشکده کویرشناسی دانشگاه سمنان، ایران
2 دانشیار گروه جنگلداری، دانشگاه تربیت مدرس، نور، ایران
3 دانشیار گروه علوم و صنایع چوب و کاغذ دانشگاه تهران، ایران
عنوان مقاله [English]
In this study, the impact of ground based skidding operation on increment growths of standing beech trees placing at alongside of skid trails investigated in Hyrcanian forests. For this purpose, four abandoned skid trails were selected which 5, 10, 15 and 20 years passed from their last skidding. Each trail divided to three segments of low, medium and high traffic with regard to distance from landing and skidder traffic intensity. The number of 72 standing beech trees were sampled alongside of trails using increment borer, and annual ring width were calculated using measuring table of LINTAB 6 with 0.01 mm accuracy. The results of ring width mean comparison between years after and before skidding operation showed about 11% decreasing in trees growth of all skid trails. Ring width in all skid trails showed significant decreasing (about 18%) in mean value of wounded trees compared with sound ones. Furthermore, trees located in high traffic segments revealed lowest mean value of increment than other segments and 33% decreasing in mean annual ring width were recorded in comparison with trees placed on low traffic segments.