أثیر شدت برداشت در شیوه جنگل‌شناسی تک گزینی بر مشخصات ساختار توده‌ ممرز آمیخته

نوع مقاله : مقاله کامل علمی پژوهشی

نویسندگان

1 دکتری جنگل‌شناسی و اکولوژی جنگل، دانشکده علوم جنگل، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان، ایران

2 دانشیار، گروه جنگل‌شناسی و اکولوژی جنگل، دانشکده علوم جنگل، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان، ایران.

چکیده

سابقه و هدف: نشانه‌گذاری و برداشت درختان با شدت‌های مختلف در شیوه جنگل‌شناسی تک­گزینی تابعی از مشخصات توده، رویشگاه و نظر کارشناس است. شدت برداشت متفاوت بر توده باقی‌مانده و وضعیت تجدید حیات که آینده جنگل را معرفی می­کند تأثیر قابل‌ملاحظه‌ای دارد. تأثیر شدت برداشت بر مشخصه‌های مختلف جنگل و توده جنگلی از جمله بر ساختار جنگل‌های هیرکانی ارزیابی نشده است. پژوهش حاضر به بررسی و مقایسه مشخصه­های ساختار توده ممرز آمیخته در یک توده شاهد (بهره­برداری نشده) و توده برداشت‌شده با شدت‌های متفاوت می­پردازد.
مواد و روش‌ها: برای انجام این پژوهش از شبکه نمونه‌برداری منظم تصادفی به ابعاد 300 در 400 متر استفاده گردید. تعداد 70 قطعه‌نمونه نیم هکتاری در 24 پارسل از دو توده برداشت‌شده و شاهد، اندازه‌گیری گردید و اطلاعات درختان و خشک‌دارها در قطعات نمونه برداشت شد. با توجه به اطلاعات صورت‌مجلس برداشت، توده­ها به چهار گروه برداشت با شدت کم، متوسط، زیاد و بدون برداشت (شاهد) تقسیم گشت. برای تعیین ساختار توده از مثلث ساختار انجمن جنگلبانی فرانسه استفاده شد و با توجه به نمودار نیمه لگاریتمی، تعداد کل درختان در طبقه‌های قطری 5 سانتی‌متری بین 40 تا 90 سانتی‌متر قرار گرفتند.
یافته‌ها: تراکم گونه ممرز به‌عنوان گونه اصلی در توده برداشت­شده بیش‌تر از توده شاهد بود اما قطر برابرسینه کم‌تری داشتند. نتایج نشان داد شدت برداشت تأثیری بر مشخصه‌های ارتفاع لوری، حجم درختان و حجم خشک‌دار نداشت درحالی‌که تأثیر آن بر قطر برابرسینه و مشخصه‌های تاج‌پوشش به‌ویژه ارتفاع تنه و تاج، سطح و حجم تاج درختان معنی‌دار بود. کم‌ترین شدت برداشت بیش‌ترین تأثیر افزایشی را بر سطح تاج (47 درصد) و حجم تاج
(142 درصد) درختان ایجاد نمود و افزایش شدت برداشت در کوتاه‌مدت منجر به بهبود مشخصه حجم تجاری تنه شد. ساختار توده‌های برداشت‌شده تفاوت معنی‌داری با توده شاهد نداشت هرچند بیش‌ترین شدت برداشت باعث جوان‌تر شدن توده‌ها و ایجاد ساختار کم‌قطر و میان‌قطر شد. شدت برداشت متوسط بیش‌ترین شباهت از لحاظ قرارگیری قطعات نمونه در هفت کلاسه ساختار را با توده شاهد داشت. اغلب توده‌ها ساختاری نامنظم، قطور و میان قطر داشتند که گویای وضعیت ساختاری برای توده‌های نامنظم ناهمسال برای تمامی توده‌های ممرز آمیخته بررسی شده است.
نتیجه‌گیری: نتایج نشان داد که شیوه تک‌گزینی با شدت کم‌تر از 5/13 درصد در توده ممرز آمیخته جنگل شصت‌کلاته باعث بهبود مشخصات ساختار توده گردیده که این موضوع بیان‌کننده اهمیت و تأثیر مدیریت صحیح و اجرای مناسب شیوه تک­گزینی در حفظ و بهبود ساختار توده جنگلی ممرز آمیخته می­باشد. با توجه به نزدیکی ساختار توده در شدت برداشت متوسط (بین 5/3 تا 5/9 درصد) با توده شاهد این شدت به‌عنوان شدت بهینه در تنظیم ساختار توده ممرز آمیخته میان‌بند جنگل‌های شرق هیرکانی معرفی می‌گردد.

کلیدواژه‌ها


عنوان مقاله [English]

The effect of harvesting intensity in the single tree selection system on mixed Hornbeam stand characteristics

نویسندگان [English]

  • Mahmoud Radaei 1
  • Hashem Habashi 2
1 head of production group of management and planning organization of mazandaran
2 معاون دانشجویی
چکیده [English]

Background and Objectives: Marking and harvesting tree with different intensities in the single-tree selection method depends on stand characteristics, site conditions, and expert opinion on silvicultural practices. Different harvesting intensities have a significant effect on the remaining stands and regeneration characteristics that describe the future sustainability of the forest. The impact of harvesting intensity on forest and stand characteristics has not been studied, particularly in the Hyrcanian forests. This study investigated the silvicultural characteristics of a mixed hornbeam stand in a control and harvested stand under different harvesting intensities.
Materials and Methods: A regular random sampling layout with a size of 300 × 400 m was used in this study. A number of 70 half-hectare sample plots covering 24 management units were surveyed to measure trees and shrubs characteristics. Forest stands were classified into three harvesting intensities of low, medium, and high compared to an unharvest stand (control) based on the report of harvest council. The structural triangle of the French Forestry Association was used to determine the stand structure, and according to the semi-logarithmic diagram, the total number of trees were classified in 5 cm diameter classes between 40 and 90 cm. 
Results: The density of hornbeam as the main species in the harvested stands was higher than that of the control stand, but it had a smaller diameter at the breast height. The results showed that harvesting intensity had no effect on the Lorey’s height, tree volume and deadwood volume, while its effect on diameter at the breast height, crown characteristics, such as trunk and crown height and canopy volume, was significant. The lowest harvesting intensity had the greatest additive effect on tree crown (47%) and tree canopy volume (142%). Increasing harvest intensity in the
short-term improved the commercial characteristics of trunk volume.
The structure of the harvested stands was not significantly different
from the control stand, although the highest harvesting intensity rejuvenated the stand structure with small to medium diameter classes. Intermediate harvesting intensity in terms of placement of sample pieces
in seven structural classes was most similar to the control stand. Most
of the stands had an irregular structure with an intermediate and large diameter, indicating the structural state of irregular uneven-aged for all mixed hornbeam stands.
Conclusion: The results showed that harvesting intensity below 13.5% improved stands characteristics in mixed hornbeam stands, indicating the importance of forest management treatments and the impact of implementing a single tree selection silviculture on improving stand structure. Due to the proximity of the stand structure at the medium harvesting intensity (between 3.5 and 9.5%) with the control stand, this level of intensity is introduced as an optimal treatment to adjust the structure of the mixed hornbeam stands in eastern Hyrcanian forests.

کلیدواژه‌ها [English]

  • Stem height
  • "."selection system"
  • "Stand structure"
  • "Harvest intensity"
  • "Carpinus
1.Shariatnezhad, Sh. 2001. Comparison of peer-to-peer and non-peer forestry techniques in Golband - Noshahr
forests. Iranian J. of Natural Resources. 54: 2. 131-142. (In Persian)
2.Storch, F., Kändler, G., and Bauhus, J. 2019. Assessing the influence of harvesting intensities on structural diversity of forests in south-west Germany. J. Forest Ecosystems. https:// doi.org/10.1186/s40663-019-0199-6.
3.Levers, Ch., Verkerk, P.J., Müller, D., Verburg, P.H., Butsic, V., Leitão, P.J., Lindner, M., and Kuemmerle, T. 2014. Drivers of forest harvesting intensity patterns in Europe. J. of Forest Ecology and Management. 315: 160-172.
4.Radaei, M., Habashi, H., Rahmani, R., Shataee, Sh., and Sohrabi, H. 2021. The Effect of harvesting intensity in single-tree selection on biomass of hornbeam - Persian ironwood stand. J. of Forest Research and Development. 7: 3. 359-373. (In Persian)
5.Hassanzad Navroodi, I., and Seyedzadeh, H. 2013. Effects of Shelterwood method on some important forest stands features in Shafarood District Nine of Guilan. J.of Iranian Forests Ecology. 1: 2. 41-55. (In Persian)
6.Pourbabaei, H., and Ranjavar, A. 2008. The effect of gradual-refuge approach on plant species diversity in Eastern beech forests. Iranian J. of Forest and Poplar Research. 16: 1. 61-73. (In Persian)
7.Moridi, M., Sefidi, K., and Etemad, V. 2015. Stand characteristics of mixed oriental beech (Fagus orientalis Lipsky) stands in the stem exclusion phase, Northern Iran. European J. of Forest Research. 134: 4. 693-703. (In Persian)
8.Kakavand, M., Marvie Mohadjer, M.R., Sagheb Talebi, Kh., and Sefidi, K. 2015. Structural diversity of mixed beech stands in the middle stage of succession) case study: Gorazbon, Kheyrood forest, Nowshahr). Iranian J. of Forest and Poplar Research. 22: 3. 411-422.(In Persian)
9.Sefidi, K., Esfandiary Darabad, F., and Azaryan, M. 2016. Effect of topography on tree species composition and volume of coarse woody debris in an Oriental beech (Fagus orientalis Lipsky) old growth forests, Northern Iran. J.of Forest-Biogeosciences and Forestry.9: 658-665. (In Persian)
10.Amiri, A. 2018. The study of some silvicultural characteristics of an unlogged mixed oriental beech stand in the Golesatan province. J. of Plant research. 31: 3. 756-768. (In Persian)
11.Falk, K.J., Burke, D.M., Elliott, K.A., and Holmes, S.B. 2008. Effects of single-tree and group selection harvesting on the diversity and abundance of spring forest herbs in deciduous forests in Southwestern Ontario. J. of Forest Ecology and Management. 255: 7. 2486-2494.
12.Karamdost Marian, B., Bonyad, A., and Tavankar, F. 2019. Effect of harvest intensity on volume growth of mixed beech stands in Asalem Nav forests. J. of Forest Research and Development.4: 4. 534-547. (In Persian)
13.Seyd, S.Z., Moayeri, M.H., and Mohammadi, J. 2015. Comparison of tree species diversity in the beech managed (selection cutting) and unmanaged stands (case study: Shastkalateh forest- Gorgan). J. of plant Research. 4: 28.784-793. (In Persian)
14.Jaafar, W.M., Woodhouse, I.H.,Silva, C.A., Omar, H., and Hudak, A.T. 2017. Modelling individual tree aboveground biomass using discrete return LiDAR in lowland dipterocarp forest of Malaysia, J. of Tropical Forest Science. 29: 4. 465-484.
15.Carrer, M., Castagneri, D., Popa, I., Pividori, M., and Lingua, E. 2018. Tree spatial patterns and stand attributes in temperate forests: The importance of plot size, sampling design, and null model. J. Forest Ecology and Management. 407: 125-134.
16.Feldmann, E., Glatthorn, J., Hauck, M., and Leuschner, Ch. 2018. A novel empirical approach for determining the extension of forest development stages in temperate old‑growth forests. European J. of Forest Research.137: 321-335.
17.Hassanzad, A., Seyedi, N., and Seyfolahian, H.R. 2009. Investigation of changes in quantitative and qualitative characteristics of forest stands after a period of forestry. J. of Iranian Forest.1: 4. 301-311. (In Persian)
18.Crow, T.R., Buckly, D.S., Nauertz, E., and Zasada, J.C. 2002. Effects of management on the composition and structure of Northern hardwood forests in upper Michigan. J. of Forest Science. 48: 1. 129-145.
19.Amini, M., Sagheb Talebi, Kh., Khoronkeh, S., and Amini, R. 2009. Investigation of forestry characteristics in mixed beech-hornbeam stands, Zalemrood, Mazandran. Iranian J. of Forest and Poplar Research. 18: 1. 21-34. (In Persian)
20.Ghasemi, A. 2018. The study of some ecological properties in control and managed by single selection method parcels (a case study: Series 4 - Section 2- Haftkhal, NekaChoob). M.Sc. Thesis, Sari Agricultural Sciences and Natural Resources University. 58p. (In Persian)
21.Sefidi, K., and Marvie Mohadjer, M.R. 2010. Characteristics of coarse woody debris in successional stages of natural beech (Fagus orientalis) forests of Northern Iran. J. of Forest Science.56: 7- 17. (In Persian)
22.Amiri, M., Dargahi, D., Azadfar, D., and Habashi, H. 2009. Comparison Structure of the natural and managed Oak (Quercus castaneifolia) Stand (shelter wood system) in Forest of Loveh, Gorgan. J. of Agricultural Sciences and Natural Resources. 15: 6. (In Persian)
23.Kialashaki, A., and Asadpour, D. 2011. Investigation of the effects of breeding operations on managed and control stands. J. of Natural Resources Science and Technology. 6: 1. 75-87. (In Persian)
24.Paritsis, J., and Aizen, M.A. 2008. Effects of exotic conifer plantations on the biodiversity of understory plants, epigeal beetlets and birds in Notofagus dombeyi forests J. of. Forest Ecology and Management. 255: 1575-1583.
25.Schütz, J.P. 2004. Opportunistic methods of controlling vegetation, inspired by natural plant succession dynamics with special reference to natural out mixing tendencies in a gap regeneration. Annals of Forest Science. 61: 2. 149-156.
26.Battaglia, L.L., Sharitz R.R., and Minchin, P.R. 1999. Patterns of seedling and overstory composition along a gradient of hurricane disturbance in an old-growth bottomland hardwood community. Canadian J. of Forest Research. 29: 1. 144-156.
27.Angers, V.A., Messier, C., Beaudet, M., and Leduc, A. 2005. Comparing composition and structure in old- growth and harvested (selection and diameter limit cuts) Northern hardwood stands in Quebec. J. of Forest Ecology and Management. 217: 275-293.
28.Barzin, M., Mohammadi, J., Shataei, Sh., and Mosavinejad, S.H. 2017. Comparison of quantitative and qualitative characteristics of forest stands structure in managed and unmanaged forest stands (case study of Loveh forestes and Khandushan forests plans. J. of Natural Resources Science and Technology. 24: 4. (In Persian)
29.Anisi, A., Kiadaliri, H., Akhavan., R., and Babaye, S. 2009. Impact of management on quantitative and qualitative characteristics of forest compared to control forest. Iranian J. of Forest and Poplar Research.17: 4. 615-626. (In Persian)
30.Tavankar, F., Bonyad A.E., and Majnoniyan, B. 2011. Investigation of stand damage due to cutting of grassland and logging in Guilan Nava Asalem forest. J. of Environmental Studies.37: 59. 89-98. (In Persian)
31.Bebber, D.P., Cole, W.G., Thomas, S.C., Balsillie, D., and Duinker, P. 2005. Effects of retention harvests on structure of old-growth Pinus strobus L. stands in Ontario. J. of Forest Ecology and Management, 205: 91-103.
32.Javanmiri Pour, M., Marvie Mohadjer, M.R., Zobeiri, M., Etemad, V., and Jourgholami, M. 2017. Quantitative changes of forest stand structure through full calipering method (Case Study: Gorazbon district, Kheyrud Forest, Noshahr). Iranian J. of Forest research. 8: 4. 493-505. (In Persian)
33.Sagheb-Talebi, Kh., Parhizkar, P., Hassani, M., Pourhashemi, M., Mirkazemi, S.Z., Karimidoost, A., Maghsoudlou, M.K., Ghorbani, H., Mortazavi, M., Seyedi, M., Rafiee, F., and Nourolahi, S.S. 2021. Structure of intact mixed broad-leaved stands in Hyrcanian forests (Case study: Loveh, Golestan province). J. Forest and Wood Products. 73: 4. 439-453.
34.Javanmiri Pour, M., Marvie Mohadjer, M., Etemad, V., and Jourgholami, M. 2018. Determining structural variation in a managed mixed stand in an old-growth forest, northern Iran. J. of Forest research. 30: 5. 493-505.