ارزیابی روند تغییرات شاخص‌های رقابت به‌منظور برآورد اثر نشانه‌گذاری در جنگل راش شرقی (Fagus orientalis Lipsky) منطقه لاویج نور

نوع مقاله: علمی- پژوهشی

نویسندگان

1 استاد، گروه جنگل‌داری، دانشکده کشاورزی و منابع طبیعی، واحد علوم و تحقیقات، دانشگاه آزاد اسلامی، تهران، ایران

2 دانشجوی دکتری جنگل‌داری، دانشکده کشاورزی و منابع طبیعی، واحد علوم و تحقیقات، دانشگاه آزاد اسلامی، تهران، ایران

3 دانشیار، گروه جنگل‌داری، دانشکده کشاورزی و منابع طبیعی، واحد علوم و تحقیقات، دانشگاه آزاد اسلامی، تهران، ایران

چکیده

تغییرات بین پایه‌ای رویش متأثر از ترکیب، ساختار و رقابت بین پایه­‌ها است. بر این اساس، آگاهی از الگوی ساختار و درک مناسب از چگونگی پاسخ پایه­‌ها به تعاملات رقابتی از اهمیت قابل توجهی برخوردار است. پژوهش پیش‌رو با هدف ارزیابی روند تغییرات شاخص‌­های رقابت در اثر اقدامات مدیریتی در جنگل­ راش (Fagus orientalis Lipsky) خالص (پارسل مدیریت شده به مساحت 36 هکتار) در منطقه لاویج شهرستان نور، استان مازندران، انجام شد. کلیه پایه­‌های نشانه­‌گذاری شده (58 پایه) پیش از قطع مکان­‌یابی شده و به‌عنوان پایه هدف درنظر گرفته شدند. به مرکزیت پایه هدف و به شعاع 3/5 برابر شعاع تاج پایه هدف، قطعه‌نمونه دایره­‌ای پیاده شد و فاصله، آزیموت، قطر برابر سینه، ارتفاع، ارتفاع شروع تاج و شعاع تاج در جهت­‌های مختلف کلیه پایه­‌ها با قطر بیشتر از 7/5 سانتی‌­متر اندازه­‌گیری شد. به­‌منظور بررسی رقابت، از شاخص‌­های وابسته به فاصله نظیر جرارد، بلا، هگی و براث استفاده شد. نتایج نشان داد که توده‌­های مورد بررسی میانسال و بیشتر دخالت­‌ها در طبقه میان‌قطر انجام شده بود. همچنین، پس از نشانه­‌گذاری، در مقدار شاخص‌­های رقابت تغییر معنی­‌داری ایجاد نشده بود. بر این اساس، اقدامات مدیریتی (نشانه­‌گذاری) در سطح توده هدفمند نبوده و به روند تغییرات رقابت پایه‌­ای توجه نشده است. بنابراین، با توجه به اهمیت عامل رقابت و ارتباط آن با پارامترهای اندازه‌­ای توده، باید در اقدامات مدیریتی به روند تغییرات آن توجه شود.

کلیدواژه‌ها


عنوان مقاله [English]

Evaluation of competition indices to assess the effect of management interventions on oriental beech (Fagus orientalis Lipsky) forest of Lavij- Noor region, Mazandaran province

نویسندگان [English]

  • Asadollah Mataji 1
  • Reza Sheydaei 2
  • Hadi Kiadaliri 3
1 Prof., Department of Forestry, Faculty of Agriculture and Natural Resources, Science and Research Branch, Islamic Azad University, Tehran, Iran
2 Ph.D. Student Forestry, Faculty of Agriculture and Natural Resources, Science and Research Branch, Islamic Azad University, Tehran, Iran
3 Associate Prof., Department of Forestry, Faculty of Agriculture and Natural Resources, Science and Research Branch, Islamic Azad University, Tehran, Iran
چکیده [English]

Tree to tree variation in growth results from compositional complexity, stand structure and competition. Therefore, it is essential to know how trees respond to competitive interactions. This study aims to evaluate of competition indices in order to assessment of management interventions effects in pure beech (Fagus orientalis Lipsky) stands (with 36 hectares) in Lavij- Noor region of Mazandaran province. For this purpose, the positions of all 58 marked trees were recorded as cored trees. Competition plots centered on the cored tree with radius of 3.5 × the cored tree crowns were established. The following attributes were measured for each tree (≥ 7.5 cm diameter at breast height (DBH)) within the plots: X and Y coordinates (m), total height, DBH, crown diameter at the base of the living crown in different directions and crown length. In order to quantify the competition level by each of the cored trees, 4 different distance-independent indices including Gerrard, Bella, Hegyi and Braathe were used. The results showed that the studied stands were middle-aged, the major interventions were in the middle DBH classes, and there was no significant change in the amount of competition indices following the interventions. Accordingly, the management interventions (marking) were not targeted and the process of individual tree competition changes was not measured. Therefore, the process of competition changes is necessary to be considered in stand management due to the high importance of the competition factor and its relation to the stand parameters.

کلیدواژه‌ها [English]

  • Distance-independent indices
  • Hyrcanian forests
  • stand structure

- Aakala, T., Fraver, S., D’Amato, A.W. and Palik, B.J., 2013. Influence of competition and age on tree growth in structurally complex old-growth forests in northern Minnesota, USA. Forest Ecology and Management, 308: 128-135.

- Anonymous, 2011. Forest management plan of Lavij, district No. 2. Forests, Range and Watershed Management Organization, Tehran, 240p (In Persian).

- Bella, I.E., 1971. A new competition model for individual trees. Forest Science, 17(3): 364-372.

- Biging, G.S. and Dobbertin, M., 1995. Evaluation of competition indices in individual tree growth models. Forest Science, 41(5): 360-377.

- Bollandsas, O.M. and Naesset, E., 2009. Weibull models for single-tree increment of Norway Spruce, Scots Pine, Birch and other broadleaves in Norway. Scandinavian Journal of Forest Research, 24(1): 54-54.

- Braathe, P., 1980. Height increment of young single trees in relation to height and distance of neighboring trees. Mitteilungen der Forstlichen Bundesversuchsanstalt, 130(3): 43-48.

- Bugmann, H., 2001. A review of forest gap models. Climatic Change, 51(3-4): 259-305.

- Contreras, M.A. and Chung, W., 2011. A modeling approach to estimating skidding costs for individual trees for thinning operations. Western Journal of Applied Forestry, 26(3): 133-146.

- Coomes, D.A. and Allen, R.B., 2007. Mortality and tree-size distributions in natural mixed-age forests. Journal of Ecology, 95(1): 27-40.

- Daniels, R.F., Burkhart, H.E. and Clason, T.R., 1986. A comparison of competition measures for predicting growth of loblolly Pine trees. Canadian Journal Forest Research, 16(1): 1230-1237.

- Eid, T. and Tuhus, E., 2001. Models for individual tree mortality in Norway. Forest Ecology and Management, 154: 69-84.

- Gerrard, D.I., 1969. Competition quotient: A new measure for the competition affecting individual forest trees, Michigan State University. Agriculture Research Station Research Bulletin, 20(6): 1-32.

- Hartmann, H., Beaudet, M., Mazerolle, M.J. and Messier, C., 2009. Sugar maple (Acer saccharum Marsh) growth is influenced by close conspecifics and skid trail proximity following selection harvest. Forest Ecology and Management, 258(1): 823-831.

- Hegyi, F., 1974. A simulation model for managing Jack pine stands. Proceedings of IUFRO meeting S4.01.04 on Growth models for tree and stand simulation, Royal College of Forestry, Stockholm, Sweden,  1974: 74-90.

- Holmes, M.J. and Reed, D.D., 1991. Competition indices for mixed species northern hardwoods. Forest Science, 37(5): 1338-1349.

- Keddy, P.A., 1989. Competition. Chapman and Hall, London, 224p.

- Kubota, Y. and Hara, T., 1995. Tree competition and species coexistence in a sub-boreal forest, northern Japan. Annals of Botany, 76(5): 503-512.

- Ledermann, T., 2010. Evaluating the performance of semi-distance-independent competition indices in predicting the basal area growth of individual trees. Canadian Journal of Forest Research, 40(4): 796-805.

- Lexer, C., 2005. Barrier to gene flow between two ecologically divergent Populus species, P. alba (white poplar) and P. tremula (European aspen): The role of ecology and life history in gene introgression. Molecular Ecology, 14(4): 1045-1057.

- Lorimer, C.G., 1983. Tests of age-independent competition indices for individual trees in natural hardwood stands. Forest Ecology and Management, 6(1): 343-360.

- Marvi Mohajer, M.R., 2005. Silviculture. University of Tehran Press, Tehran, 387p (In Persian).

- Moore, J.A., Budelsky, C.A. and Schlesinger, R.C., 1973. A new index representing individual tree competitive status. Canadian Journal of Forest Research, 3(3): 495-505.

- Pacala, S.W., Canham, C.D., Saponara, J., Silander, J.A., Kobe, R.K. and Ribbens, E., 1996. Forest models defined by field measurements: Estimation, error analysis and dynamics. Ecological Monographs, 66(1): 1-43.

- Parish, R. and Antos, J.A., 2004. Structure and dynamics of an ancient montane forest in coastal British Columbia. Oecologia, 141(4): 562-576.

- Pedersen, R., Nesset, E., Gobakken, T. and Bollandas, O.M., 2013.On the evaluation of competition indices -The problem of overlapping samples. Forest Ecology and Management, 310: 120-133.

- Rivas, J.J.C., Gonzàlez, J.G., Aguirre, O. and Hernàndez, F.G., 2005. The effect of competition on individual tree basal area growth in mature stands of Pinuscooperi Blanco in Durango (Mexico). European Journal of Forest Research, 124(1): 133-142.

- Robert, S.D. and Harington, C.A., 2008. Individual tree growth response to variable-density thinning in coastal Pacific Northwest forests. Forest Ecology and Management, 255: 2771-2781.

- Stage, A.R. and Ledermann, T., 2008. Effects of competitor spacing in a new class of individual-tree indices of competition: semi-distance-independent indices computed for Bitterlich versus fixed-area plots. Canadian Journal of Forest Research, 38(4): 890-898.

- Tomé, M. and Burkhart, H.E., 1989. Distance-dependent competition measures for predicting growth of individual trees. Forest Science, 35(3): 816-831.

- Woodall, C.W., Fiedler, C.E. and Milner, K.S., 2003. Inter tree competition in uneven-aged ponderosa pine stands. Canadian Journal of Forest Research, 33(9): 1719-1726.