ارزیابی روش‌های اندازه‏گیری تاج درختان شاخه‏زاد در جنگل‌های زاگرس با استفاده از تصاویر هوایی UltraCam-D

نوع مقاله : مقاله پژوهشی

نویسندگان

1 استادیار، بخش مدیریت مناطق بیابانی، دانشکدة کشاورزی دانشگاه شیراز، شیراز، ایران

2 دانشجوی کارشناسی ارشد، بخش مدیریت مناطق بیابانی، دانشکدة کشاورزی دانشگاه شیراز، شیراز، ایران

چکیده

تاج پوشش مهم‌ترین ویژگی زیست‏سنجیِ مورد استفاده در مدیریت جنگل‌های زاگرس بوده که اندازه‏گیری این ویژگی در درختان شاخه‏زاد با شکل تاج نامتقارن اهمیت بیشتری دارد. بنابراین، این مطالعه با هدف بررسی صحت و دقت روش‌های میدانی تعیین مساحت تاج درختان شاخه‏زاد بلوط ایرانی و امکان برآورد قطر متوسط تاج این درختان با استفاده از تصاویر هوایی UltraCam-D انجام گرفت. بدین‌منظور، در یک محدوده به مساحت 30 هکتار در جنگل‌های بلوط ایرانی در جنگل‌های استان کهگیلویه و بویراحمد دو قطر بزرگ و کوچک تاج 125 پایه درخت بلوط ایرانی شاخه‏زاد اندازه‏گیری شد. مساحت تاج هر‌یک از آن‌ها نیز از تصاویر هوایی UltraCam-D منطقة مورد مطالعه محاسبه شد. سپس دو شکل بیضی و دایره و دو روش محاسبۀ قطر تاج متوسط هندسی و حسابی ارزیابی شدند. نتایج نشان داد مساحت واقعی تاج درختان با هر‌یک از روش‌های اشاره‌شده اختلاف معنی‏داری نداشته و از صحت کافی برخوردارند. البته محاسبة مساحت تاج درختان مذکور با شکل دایره با قطر متوسط حسابی، 9/8 درصد، و با شکل دایره با قطر متوسط هندسی و شکل بیضی، 7/7 درصد بیشتر از مقدار واقعی بود. همچنین استفاده از شکل بیضی بیشترین دقت را در برآورد مساحت تاج در مقایسه با دو روش دیگر ارائه داد. برآورد قطر متوسط تاج درختان شاخه‏زاد بلوط ایرانی نیز از روی تصاویر هوایی مذکور و با استفاده از یک مدل درجة سوم بدون اختلاف معنی‌‌دار از مقدار واقعی ممکن است.

کلیدواژه‌ها

عنوان مقاله [English]

Assessment of Crown Measurement Techniques in Coppice Trees of Zagros Forests by UltraCam-D Aerial Imagery

نویسندگان [English]

  • Yousef Erfanifard 1
  • Masoumeh Mouselo 2
1 Assistant Professor, Department of Desert Region Management, College of Agriculture, Shiraz University, Shiraz, I.R. Iran
2 M.Sc. student, Department of Desert Region Management, College of Agriculture, Shiraz University, Shiraz, I.R. Iran
چکیده [English]

Crown cover is one of the most important biometric characteristics applied in Zagros forests
management that its measurement is more important in coppice trees because of their asymmetric
crown shape. The aim of this research was investigating on the accuracy and precision of different
mensuration methods of crown area measurement in Persian Oak coppice trees and the possibility of
mean crown diameter estimation of these trees by UltraCam-D imagery. The maximum and minimum
crown diameters of 125 Persian Oak coppice trees were inventoried in a 30 ha plot in the forests of
Kohgiluye-BoyerAhmad province. The crown area of each tree was measured on UltraCam-D aerial
imagery of the study area. Two circular and elliptical shapes and two mathematical and geometric
methods of calculating mean crown diameter were analyzed in this respect. The results showed that
the applied methods have no significant difference with the true crown area and they were accurate
enough. Although the crown area of the trees with circular shape and mathematical mean diameter
were 8.9 percent and with circular shape and geometric mean diameter and elliptical shape were 7.7
percent greater than the true values. The elliptical shape was also more precise in measuring the crown
area than two other methods. It was also possible to estimate the mean crown diameter of Persian Oak
coppice trees applying the aerial imagery and cubic models with no significant difference from the
true values.

کلیدواژه‌ها [English]

  • circular crown shape
  • Coppice
  • crown cover
  • elliptical crown shape
  • Persian Oak
  • UltraCam-D aerial imagery
  • Zagros

مراجع

[1]. Kangas, A., and Maltamo, M. (2006). Forest inventory, Springer, The Netherlands.
[2]. Ke, Y., and Quackenbush, L.J. (2009). Individual tree crown detection and delineation from high spatial resolution imagery using active contour and hill-climbing methods. ASPRS Annual Conference, March 9-13, Maryland, USA, pp. 2-11.
[3]. Anttila, P. (2005). Assessment of manual and automated methods for updating stand-level forest inventories based on aerial photography. Ph.D. thesis, University of Joensuu, Finland.
[4]. Korhonen, L., Korhonen, K.T., Rautiainen, M., and Stenberg, P. (2006). Estimation of forest canopy cover: a comparison of field measurement techniques. Silva Fennica, 40(4): 577-588.
[5]. Chopping, M., Moisen, G.G., Su, L., Laliberte, A., Rango, A., Martonchik, J.V., and Peters, D.P.T. (2008). Large area mapping of southwestern forest crown cover, canopy height, and biomass using the NASA Multiangle Imaging Spectro-Radiometer. Journal of Remote Sensing of Environment, 112: 2051-2063.
[6]. Behbahani, N., Fallah Shamsi, S.R., Farzadmehr. J., Erfanifard, S.Y., and Ramazani Gask, M. (2009). Using vegetation indics of ASTER-L1B imagery to estimate single trees crown cover in arid rangelands, Case study: Tag-Ahmadshahi, Southern of Khorassan. Iranian Journal of Rangeland, 4(1): 93-103.
[7]. Erfanifard, Y., Zobeiri, M., Feghhi, J., and Namiranian, M. (2007). Estimation of crown cover on aerial photographs using shadow index (Case study: Zagros forests, Iran). Iranian Journal of Forest and Poplar Research, 15(3): 278-288.
[8]. West, P.W. (2009). Tree and forest measurement, Springer, Germany.
[9]. Adame, P., Hynynen, J., Canellas, I., and Rio, M. (2008). Individual-tree diameter growth model for rebollo oak (Quercus pyrenaica Wild.) coppices. Journal Forest Ecology and Management, 255: 1011-1022.
[10]. Jazirehi, M.H., and Ebrahimi Rostaghi, M. (2003). Silviculture in Zagros, Tehran University Press, Tehran.
[11]. Sagheb-Talebi, K., Sajedi, T., and Yazdian, F. (2003). Forests of Iran. Research Institute of Forest and Rangelands, No. 339, Tehran.
[12]. Fattahi, M. (2005). Methods of management in Zagros forests. Journal of Dehati, 52(3): 23-42.
[13]. Andarz, Z., Fallaf, A., Oladi, G., and Babaee, S. (2009). Mensuration of urban forests using aerial photographs. Iranian Journal of Environment, 35 (50): 55-62.
[14]. Parma, R., and Shataee, SH. (2010). Capability study on mapping the diversity and canopy cover density in Zagros forest using ETM+ images (Case study: Ghalajeh forests, Kirmanshah province). Iranian Journal of Forest, 2(3): 231-242.
[15]. Negahdarsaber, M. (1993). Measurement of suitable parameters in the inventory of southern conservative Zagros forests. M.Sc. thesis, University of Tehran, Iran.
[16]. Nasset, E., (2004). Practical large-scale forest stand inventory using a small-footprint airborne scanning laser. Scandinavian Journal of Forest Research, 19: 164-179.
[17]. Greenberg, J.A., Dobrowski, S.Z., and Vanderbilt, V.C. (2009). Limitations on maximum tree density using hyperspatial remote sensing and environmental gradient analysis. Journal of Remote Sensing of Environment, 113: 94-101.
[18]. Namiranian, M. (2007). Measurement of tree and forest biometry, University of Tehran Press, Tehran.
[19]. Haidari, R.H. (2008). Distance sampling methods in forest inventory, Razi University Press, Kermanshah.
[20]. Talebi, M., Sagheb-Talebi, KH., and Jahanbazi, H. (2008). Site demands and some quantitative and qualitative characteristics of Persian Oak (Quercus brantii Lind1.) in Chaharmahal & Bakhtiari Province (western Iran). Iranian Journal of Forest and Poplar Research, 14(1): 67-79.
[21]. Rudnicki, M., Silins, U., and Lieffers, V. (2004). Crown cover is correlated with relative density, tree slenderness and tree hight in Logepole Pine. Journal of Forest Science, 50(3): 356-363.
[22]. Lang, M. and Kurvits, V. (2007). Restoration of tree crown shape for canopy cover estimation. Journal of Forestry Studies, 46: 23-34.
[23]. Salehi, A., Wilhelmsson, E., and Soderberg, U. (2008). Land cover changes in a forested watershed, southern Zagros, Iran. Journal of Land Degradation & Development, 19: 542-553.
[24]. Aghakhani, S., and Metaji, A. (2009). The study of ecological seriate structure of Markazi province jungles (case study: Shazand city Oak jungles). Journal of Plant Ecophysiology, 1(3): 53-63.
[25]. Bordbar, K., Sagheb-Talebi, Kh., Hamzehpour, M., Joukar, L., Pakparvar, M., and Abbasi, A.R. (2010). Impact of environmental factors on distribution and some quantitative characteristics of Manna Oak (Quercus brantii Lind1.) in Fars province. Iranian Journal of Forest and Poplar Research, 18 (3): 390-404.
[26]. Logli, F., and Joffre, R. (2001). Individual variability as related to stand structure and soil condition in a Mediterranean oak coppice. Journal of Forest Ecology and Management, 142: 53-63.
[27]. Garcia, M., and Retana, J. (2004). Effect of site quality and shading on sprouting patterns of holm oak coppices. Journal of Forest Ecology and Management, 188: 39-49.
[28]. Zobeiri, M. (2007). Forest inventory: measurement of tree and forest, 2nd Ed., University of Tehran Press, Tehran.
[29]. Fensham, R.J., Fairfax, J.E., Holman, J.E., and Whitehead, P.J. (2002). Quantitative assessment of vegetation structural attributes from aerial photography. International Journal of Remote Sensing, 23(11): 2293-2317.
[30]. Carreiras, M.B., Pereira, M.C., and Pereira, S. (2006). Estimation of tree canopy cover in evergreen oak woodlands using remote sensing. Journal of Forest Ecology and Management, 223: 45-53.
[31]. Blaschke, T. (2010). Object based image analysis for remote sensing. ISPRS Journal of Photogrammetry and Remote Sensing, 65: 2-16.
[32]. Avery, E.T. (1977). Interpretation of aerial photographs. 3th. Burgess Publication, USA.
[33]. Korpela, I. (2004). Individual tree measurements by means of digital aerial photogrammetry. Silva Fennica Monographs, 3, 93p.
[34]. Bunting, P., and Lucas, R. (2006). The delineation of tree crowns in Australia mixed species forests using hyperspectral Compact Airborne Spectrographic Imager (CASI) data. Journal of Remote Sensing of Environment, 101: 230-248.
[35]. Zobeiri, M., and Majd, A. (2010). An introduction to remote sensing technology and its application in natural resources. 8th Ed., University of Tehran Press, Tehran.   
[36]. Sohrabi, H., Zobeiri, M., and Hosseini, S. (2009). Preparation of aerial volume table using visual interpretation of digital aerial images. Iranian Journal of Forest and Wood Products, 62(3): 261-274.
[37]. Van Laar, A., and Akca, A. (2007). Forest mensuration, Springer, The Netherlands.
[38]. Koukoulas, S. and Blackburn, G.A. (2005). Mapping individual tree location, height and species in broadleaved deciduous forest using airborne LIDAR and multi-spectral remotely sensed data. International Journal of Remote Sensing, 26(3): 431-455.
[39]. Kohl, M., Magnussen, S.S., and Marchetti, M. (2006). Sampling methods, remote sensing and GIS multiresource forest inventory, Springer, Germany.
[40]. Pouliot, D.A., King, D.J., Bell, F.W., and Pitt, D.G. (2002). Automated tree crown detection and delineation in high-resolution digital camera imagery of coniferous forest regeneration. Journal of Remote Sensing of Environment, 82: 322-334.

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