میزان افت چوب و کاهش ارزش آن طی عملیات قطع درخت و بینه بری (مطالعه موردی: درختان راش و ممرز جنگل خیرود)

نوع مقاله: مقاله پژوهشی

نویسندگان

1 دانشجوی کارشناسی ‏ارشد مهندسی جنگل، دانشکدة منابع طبیعی، دانشگاه تهران، کرج، ایران

2 دانشیار گروه جنگل‌داری و اقتصاد جنگل، دانشکدة منابع طبیعی، دانشگاه تهران، کرج، ایران

چکیده

میزان ضایعات چوب و کاهش کیفیت و ارزش آن، در رابطه با عملیات قطع درخت و بینه‌بری دو گونۀ راش و ممرز و نوع صدمه در بخش نمخانۀ جنگل آموزشی ـ پژوهشی خیرود مطالعه شد. برای محاسبۀ افت چوب بر اثر قطع و انداختن درخت و بینه‏بری در بخش قطع و انداختن درخت در مجموع 250 اصله درخت، و در بخش بینه‏بری در مجموع 167 عدد گرده‏بینه از گونه‏های راش و ممرز به‌صورت تصادفی بررسی و اندازه‏گیری شدند. نتایج نشان داد که از کل حجم قطع‌شده در بین تمام گونه‏ها، 5/42 متر مکعب (9 درصد) و در بخش بینه‏بری 05/16 متر مکعب (3/10 درصد) چوب دچار انواع درجه‏های صدمه شدند. بیشتر صدمات مشاهده‌شده در چوب بر اثر عملیات قطع در این بررسی مربوط به شکاف و پارگی طولی است که حدود 46 درصد افت را شامل می‏شود. میزان افت از نوع ارتفاع زیاد کنده 3 درصد، شکستگی و خردشدگی 27 درصد، و افت جداشدگی ورقه‏ای 24 درصد شده است. میزان افت از نوع شکاف طولی گرده‏بینه صفر، جداشدگی ورقه‏ای 8/1 درصد، و خطای اندازه‏گیری 8/20 درصد شده است. بیشترین افت کیفی چوب از نوع شکاف و پارگی طولی برابر با 52/46 درصد و کمترین افت از نوع ارتفاع بیش از حد کنده 66/1 درصد است. بقیۀ گروه‏های افت که شامل شکستگی و خردشدگی و صدمه به‌صورت جداشدگی ورقه‏ای‌اند به‌ترتیب 33/21 درصد و 5/30 درصد از کل افت کیفی چوب بر اثر عملیات قطع را شامل می‏شوند.

کلیدواژه‌ها


عنوان مقاله [English]

Harvested Log Damage Associated with Motor-Manual Tree Felling and Bucking (Case Study: Beech and Hornbeam trees in Kheyrud Forest)

نویسندگان [English]

  • Zahra Ghorbani 1
  • Meghdad Jourgholami 2
1 MSc. Student, Forest Engineering, Faculty of Natural Resources, University of Tehran, Karaj, I.R.Iran
2 Associate Professor, Department of Forestry and Forest Economics, Faculty of Natural Resources, University of Tehran, Karaj, I.R.Iran
چکیده [English]

The log damage and value loss were examined by felling and bucking function, species, and damage type, in Kheyrud Forest in Namkhaneh district in the Hyrcanian Forest of Iran. In order to calculate the wood value following tree felling and bucking, 250 trees and 167 logs consisting of beech and hornbeam species were measured. There were five types of damage recorded following the tree felling operations: split damage, stump height, slab damage, splintering or breakage damage and no damage. Results showed that the total volume of damaged logs was 42.5 cubic meters (9%) for all trees. The majority of woody tissue damage is caused by splits, slab and splintering or breakage damage. Stump height consists of a small amount of volume loss. Also There were four types of damage recorded the effects of bucking operations: slab damage, log length split, measurement error and without damage. The total volume of damaged logs was 16.1 cubic meters (10.3%) for all logs. The majority of woody tissue damage consists of the measurement error. Slab and Log length split caused a small amount of volume loss. Value loss associated with splits was 46.52%, and value loss associated with high stump was 1.66%. Slabs and Splintering or breakage damage caused a small amount of average volume loss per damaged log which were 30.5 and 21.33%, respectively.

کلیدواژه‌ها [English]

  • bucking
  • Forest harvesting
  • log damage
  • tree felling
  • wood loss
[1]. Murphy, G., and Twaddle, A.A. (1986). Techniques for the assessment and control of log value recovery in the New Zealand forest harvesting industry. IN Improving productivity through forest engineering: Proceedings of the 9th Annual Council on Forest Engineering. September 29-October 2, 1985. 25p.

[2]. Seymouret, R.S., Hannah, P.R., Grace, J.R., and Marquis, D.A. (1986). Silviculture: The next thirty years, the past thirty years. Journal of Forestry, (6): 31–38.

[3]. Boston, k., and Dysart, G. (2000) .A comparison of felling techniques on sump height and log damage with economic interpretations. Western Journal of Applied Forestry, 15(3): 59–61.

[4]. Gallagher, T.V., Shaffer, R.M., and Stuart, W.B. (1985). An assessment of shear damage to southern pine sawlogs. Forest Products Journal, 35(11/12): 87–91.

[5]. Greene, W.D., and McNeel, J.F. (1989). Potential costs of shear damage in a southern pine chip-n-saw mill. Forest Products Journal, 39(5): 12–18.

[6]. Shaffer, R.M., Swiatlo, J.A., Stuart, W.B., and Wengert, E.M. (1990). An analysis of shear damage at two southern pine sawmills. Forest Products Journal, 40(6): 33–36.

[7]. Greene, W.D., and McNeel, J.F. (1987). Productivity, costs, and levels of butt damage with a Bell Model T feller-buncher. Forest Products Journal, 37(11/12): 70–74.

[8]. Middleton, G.R., and Munroe, B.D. (1987). Evaluating two methods of coping with tree shear damage at the sawmill. Forest Products Journal, 37(7/8): 17–22.

[9]. Sessions, J. (1988). Making better tree-bucking decisions in the woods. Journal of Forestry, (10): 43–45.

[10]. Sarikhani, N. (1972). The amount of wood waste during logging operations in Iranian forests in different work conditions. Faculty of Natural Resources publication, No. 3, Tehran Univ. 30p.

[11]. Emadi, S. (1997). Determining of wood waste in different stages of logging process, M.Sc. thesis. Faculty of Natural Resources, Tarbiat Modares University. 91p.

[12]. Tavankar, F., and Einollahy, Y. (2010). Logging in northern forests of Iran. Asian Journal of Chemistry,22(2):1615–1618.

[13]. Keivan Behjou, F., Majnounian, B., Namiranian, M., Saeed, A., and Feghhi, J. (2010). Determination of Volume and Value Loss in Logging Operations. Journal of Forest and Wood Products, 63(3): 299–304.

[14]. Etehadi Abari, M. (2010). Quantitative and qualitative of wood loss following motor-manual tree felling. M.Sc. Seminar 1. Faculty of Natural Resources, Tehran University. 50p.

[15]. Pearce, J.K., and Stenzel, G. (1972). Logging and Pulpwood Production. The Ronald Press Co. New York. 453p.

[16]. Soleimanzade, E. (1987). Appropriate stump height to reduce waste during felling operation in the forest of beech and hornbeam trees. Research Institute of Forests and Rangelands. Technical Publication No. 48. Tehran. 46p.

[17]. Soltaninejad, M. (1990). Phenomenon of provide lumber and cutting waste and wood Extraction in Traditional logging in forest kheyrud noshahr. M.Sc. thesis. Faculty of Natural Resources, Tarbiat Modares University. 157p.

[18]. Vanderberg, M.R. (2002). Harvested log damage and value loss associated with two ground-based harvesting systems in central Appalachia. MSc. Thesis. Davis College of Agriculture, Forestry, and Consumer Sciences. West Virginia University. Morgantown, West Virginia. 98p.

[19]. Gerasimov, Y., and Seliverstov, A. (2010). Industrial Round-Wood Losses Associated with Harvesting Systems in Russia. Croatian Journal of Forest Engineering, 31(2): 111–126.

[20]. Anonymous, (2000). Forest management plan of Namkhaneh District, Kheyrud Educational and Research Forest in Nowshahr. Natural Recourses Faculty. University of Tehran. 360p.