نقش رژیم سایه دامنه در تراکم تاج‌پوشش و ارزیابی توان اکولوژیک جنگل‌های زاگرس (مطالعه موردی: جنگل‌های کبیرکوه شهرستان بدره، استان ایلام)

نوع مقاله: علمی- پژوهشی

نویسندگان

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

2 دانشیار، گروه جنگلداری، دانشکده علوم جنگل، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان، ایران

3 دانشیار، گروه محیط زیست، دانشکده شیلات و محیط زیست، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان، ایران

چکیده

هدف پژوهش پیش‌رو، بررسی نقش رژیم سایه دامنه در میزان تراکم تاج‌پوشش و امکان جایگزینی آن با معیار جهت دامنه در مطالعات اکولوژیکی و ارزیابی توان اکولوژی جنگل‌های کبیرکوه ایلام در حوزه رویشی زاگرس بود. برای انجام این پژوهش، ابتدا نقشه مدل رقومی ارتفاع تهیه شد و نقشه رژیم سایه دامنه از آن استخراج شد. با توجه به ارتباط مستقیم تاج‌پوشش جنگل با توان اکولوژیک رویشگاه، نقشه‌های رستری سایه دامنه و تاج‌پوشش در هم ضرب شدند و مساحت اشغال‌شده به‌وسیله تاج‌پوشش در مقادیر مختلف رژیم سایه دامنه محاسبه شد. همچنین، نقشه جهت‌های اصلی دامنه تهیه شد و در نقشه تاج‌پوشش جنگل ضرب شد. مساحت اشغال‌شده به‌وسیله تاج‌پوشش در جهت‌های مختلف دامنه نیز محاسبه شد و هیستوگرام آن ترسیم شد. درنهایت، هیستوگرام و مدل‌های رگرسیونی رابطه مقادیر مختلف رژیم سایه دامنه و درصد تاج‌پوشش جنگل تهیه شد. هیستوگرام مذکور بیانگر روند افزایش تاج‌پوشش در قبال کاهش شدت نور (افزایش سایه) بود. ضریب تبیین (R2) مدل رگرسیونی درجه دو و مدل خطی رابطه مذکور برای مقادیر با ارزش سایه بیشتر از 100، به‌ترتیب برابر با 0/58 و 0/56 به‌دست آمد. با توجه به سهولت تهیه نقشه سایه دامنه و نقش آن در پیش‌بینی تاج‌پوشش جنگل و مزیت‌های دیگری که بر نقشه جهت دامنه دارد، توصیه می‌شود که این معیار در جنگل‌های زاگرس و در جنگل‌های خشک و نیمه‌خشک دیگر، به‌عنوان یکی از عامل‌های کلیدی توان اکولوژیکی سرزمین مورد استفاده قرار گیرد.

کلیدواژه‌ها


عنوان مقاله [English]

The role of hillshade regime on canopy density and evaluation of ecological capability in the Zagros forests (Case study: Kabirkooh forest of Badreh city, Ilam province)

نویسندگان [English]

  • Ali Najafifar 1
  • Mohammad Hadi Moiyeri 2
  • Shaban Shatai-Joybari 2
  • Abdolrasoul Salman-Mahini 3
1 Ph.D. Student Silviculture and Forest Ecology, Faculty of Forest Science, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran
2 Associate Prof., Department of Forestry, Faculty of Forest Science, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran
3 Associate Prof., Department of Environment, Faculty of Fisheries and Environmental Sciences, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran
چکیده [English]

The purpose of this research was to investigate the role of hillshade values, in comparison with terrain aspect, in the canopy changes and evaluation of ecological capability in vegetation domain of Zagros forests. In conducting the research, digital elevation model (DEM) was prepared and soil map was extracted from that. Due to the direct relationship of forest canopy with the site ecological capability, the raster map of hillshade was multiplied by forest canopy; and canopy area was calculated at different values of the hillshade map. Also, the map of the main slop aspects extracted by the DEM map and that was multiplied to the map of forest canopy. Then canopy area was calculated for different aspect; and that was presented as a histogram. Thereupon, the histogram and quadratic model equation of relationship between forest canopy percent and hillshade regime was prepared, in the entire study area. The histogram and the model, show that reducing the intensity of sunlight (Rising Shadow), strong influence on the increase in canopy. Also, the quadratic regression model (R2 = 0.58) and linear regression model (R2 = 0.56) of the correlation, with 17 repetitions, obtained in the form of a square block network. Because of the easiness and the low cost of hillshade mapping, and also, its superiority over the terrain aspect map; we recommend that hillshade maps be used as one of the key factors for of land ecological capability, in the Zagros forest and other arid and semi-arid forests.

کلیدواژه‌ها [English]

  • aspect
  • canopy density
  • ecological capability
  • hillshade
  • Zagros forests

- Ahmadi Sani, N., Babai Kafaki, S. and Mataji, A., 2011. Evaluation of ecological capability of northern Zagros forests for ecotourism activities using Multi-Criteria Decision Making. Geographic Information System and Remote Sensing, 3(4): 45-64 (In Persian).

- Akpinar, E. and Usul, N., 2003. GIS in forest fires. City and Regional Planner Project Cordinator in INTA SpaceTurk, Turkey, 11p.

- Alina, C., Horia, C., Florica, M., Ioana P. and Ancuţa, R., 2013. Aspects of solar radiation analysis using ArcGis. Bulletin UASVM Horticulture, 70(2): 437-440.

- Amiri, M.J., Mahini, A.S., Hosseini, S.M. and Jalali, S.Gh., 2013. OWA analysis for ecological capability assessment in watersheds. International Journal of Environmental Research, 7(1): 241-254.

- Babaie-Kafaky, S., Mataji, A. and Sani, N.A., 2009. Ecological capability assessment for multiple-use in forest areas using GIS-based multiple criteria decision making approach. American Journal of Environmental Sciences, 5(6): 714-721.

- Barth, M., 2010. Environmental correlates of tree species distribution in old-growth forests. B.Sc. thesis, Faculty of Forest Resources, University of Washington, Washington, 41p.

- Borzoei, N., Maleknia, R. and Zeinivand, H., 2014. Ecological capability evaluation of Taf traditional-property for intensive recreation based on MCDM. Agriculture Science Developments, 3(2): 175-182.

- Christian, P. and Jean-Claude, G., 2007. Multiscale computation of solar radiation for predictive vegetation modeling. Annals of Forest Science, 64: 899-909.

- Espahbodi, K. and Tabari, M., 2004. Determining the most suitable shade rate for producing Beech (Fagus orientalis Lipsky) seedlings in a mountain nursery. Iranian Journal of Natural Resources, 57(3): 439-446 (In Persian).

- Farque, L., Sinoquet, H. and Colin, F., 2001. Canopy structure and light interception in Quercus petraea seedlings in relation to light regime and plant density. Tree Physiology, 21: 1257-1267.

- Fu, P. and Rich, P.M., 1999. Design and implementation of the Solar Analyst: an ArcView extension for modeling solar radiation at landscape scales. Proceedings of the 19th Annual ESRI User Conference, San Diego, USA.

- Fu, P. and Rich, P.M., 2000. A geometric solar radiation model and its applications in agriculture and forestry. Proceedings of the Second International Conference on Geospatial Information in Agriculture and Forestry, 10-12 Jan. 2000: 357-364.

- Gardiner, E.S. and Hodges, J., 1998. Growth and biomass distribution of cherrybark oak seedling as influenced by light availability. Forest Ecology and Management, 108:‌ 127-134.

- Gorchibeigi, K., 2001. Studying the qualitative and quantitative of the properties of beech seedlings with cavity gap surface. Ph.D. thesis, Faculty of Agriculture and Natural Resources, Islamic Azad University, Science and Research Branch, Tehran, 180p (In Persian).

- Guth, P.L., 1999. Contour line “ghosts” in USGS level 2 DEMs, photogrammetric. Engineering & Remote Sensing, 65(3): 289-296.

- Iverson, L., Dale, M., Scott, Ch. and Prasad, A., 1997. A GIS-derived integrated moisture index to predict forest composition and productivity of Ohio forests (USA). Landscape Ecology, 12: 331-348.

- Jahanpour, F., Fatahi, M., Khademi, K., Sohrabi, S.R., Karamian, R. and Biranvand, R., 2008. Studying the influence of light on surviving of pistachio saplings in Lorestan province. Report of Research Project, Published by Research Institute of Forests and Rangelands, Tehran, 66p (In Persian).

- Najafifar, A., Hoseinzadeh, J. and Pourhashemi, M., 2015. The effect of topography and habitat ecological capability in forest dieback in Ilam province. Report of Research Project, Published by Research Institute of Forests and Rangelands, 74p (In Persian).

- Najafifar, A., Sagheb Talebi, K. and Saeb, K., 2012. The role of light intensity on survival of Quercus branti saplings in relation to slope aspect and distance from seed trees in Ilam province forests. Journal of Forest and Wood Products, 64(4): 1-14 (In Persian).

- Pierce, K., Lookingbill, T. and Urban, D., 2005. A simple method for estimating potential relative radiation (PRR) for landscape-scale vegetation analysis. Landscape Ecology, 20(2): 137-147.

- Rich, P.M., Dubayah, R., Hetrick, W.A. and Saving, S.C., 1994. Using viewshed models to calculate intercepted solar radiation: applications in ecology. Technical Paper, American Society for Photogrammetry and Remote Sensing, pp: 524-529

- Sagheb Talebi, Kh., Delfan Abazari, B. and Namiranian, M., 2005. Regeneration process in natural uneven-aged Caspian beech forest of Iran. Swiss Forestry Journal, 156(12): 477-480.

- Teimoorzadeh, A., Akbarini, M., Hoseini, S. and Tabari, M., 2004. The effect of shades on survival and growth seedlings of Persian oak (Quercus macranthera F. et. M.). Pajouhesh & Sazandegi, 16(4): 12-17 (In Persian).

- Weinreich, A., 2002. Regeneration of oak in gaps: comparative studies of quality and stem-development of young oaks Libel, grown under different light condition. Journal of Ecology, 82(2): 227-237.

- Wise, S.M., 2001. Error assessment for digital terrain models. Available at: http://www.shef.ac.uk/geography/staff /wise_stephen/dtm/dtm.htm