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واکاوی زوال جنگلهای استان ایلام و ارتباط آن با تغییرات بارش | ||
| تحقیقات جنگل و صنوبر ایران | ||
| مقاله 11، دوره 23، شماره 3، مهر 1394، صفحه 502-515 اصل مقاله (2.27 M) | ||
| نوع مقاله: علمی- پژوهشی | ||
| شناسه دیجیتال (DOI): 10.22092/ijfpr.2015.105655 | ||
| نویسندگان | ||
| قاسم عزیزی* 1؛ مرتضی میری2؛ حسین محمدی3؛ مهدی پورهاشمی4 | ||
| 1دانشیار، دانشکده جغرافیا، دانشگاه تهران | ||
| 2دانشجوی دکتری اقلیم‌شناسی، دانشکده جغرافیا، دانشگاه تهران | ||
| 3استاد، دانشکده جغرافیا، دانشگاه تهران | ||
| 4دانشیار پژوهش، مؤسسه تحقیقات جنگلها و مراتع کشور | ||
| چکیده | ||
| امروزه به دلیل بروز پدیده زوال بلوط، گستره قابل توجهی از جنگلهای زاگرس دچار خشکیدگی شده است. هدف اصلی پژوهش پیش رو تعیین گستره پوشش‌های جنگلی استان ایلام و بررسی روند تغییرات زمانی آنها طی دوره 14ساله (2000 الی 2013) در ارتباط با تغییرات بارش می‌باشد. برای این منظور از تکنیک‌های سنجش از دور و سیستم اطلاعات جغرافیایی استفاده شد. داده‌های مورد استفاده دربرگیرنده تصاویر NDVI سنجنده مادیس با فواصل 16روزه، تصاویر موجود در آرشیو Google earth و نقاط کنترل زمینی، داده‌های اقلیمی ایستگاه‌های همدید، داده‌های درازمدت GPCC و داده‌های بارش ماهواره TRMM بودند. تعیین تعداد طبقات مطلوب برای شناسایی پوشش‌های منطقه و درنهایت جنگلها با استفاده از روش نظارت‌نشده و تکنیک ISODATA و شاخص‌های تفکیک واگرایی کمترین و میانگین انجام شد. نتایج به‌دست‌آمده از طبقه‌بندی نشان داد که تعداد طبقه 35 برای بررسی سالانه و طبقه 30 برای بررسی درازمدت، منطقیترین تعداد طبقه مطلوب برای پوشش‌های این استان هستند. نمودار طیفی نیز بیانگر دوره رشد جنگلهای استان ایلام از اواخر بهمن تا اوایل مرداد بود که اوج سبزینگی آنها نیز در اواسط اردیبهشت بود. نمودار روند تغییرات NDVI مناطق جنگلی طی دوره 14ساله بیانگر اولین کاهش قابل توجه سبزینگی در سال 2005 (1383) و به میزان بیشتری در سال 2008 به‌همراه روند نزولی آن برای سه سال انتهایی دوره بود. نتایج به‌دست‌آمده از بررسی داده‌های بارش ایستگاهی و شبکه‌ای نشاندهنده روند منفی بارش در مقیاس‌های زمانی سالانه و ماهانه بر پوشش‌های مختلف استان ایلام و جنگلهای منطقه بود. در مناطق جنگلی استان، روند منفی بارش در سطوح اطمینان 90 و 95 درصد معنی‌دار بود. طی فصل رشد جنگلها، بیشترین روند منفی بارش در اسفند (هم‌زمان با اوایل دوره رشد جنگل) مشاهده شد. بررسی ارتباط بین میزان NDVI و روند بارش نشان داد که یکی از عامل‌های اصلی خشکیدگی و کاهش سبزینگی در جنگلهای این منطقه، کاهش معنی‌دار بارش و ایجاد تنش خشکی در مقیاس سالانه و به ویژه فصل رشد می‌باشد. | ||
| کلیدواژه‌ها | ||
| تفکیک‌پذیری؛ زوال بلوط؛ GPCC؛ ماهواره TRAA؛ ماهواره TRMM | ||
| عنوان مقاله [English] | ||
| Analysis of relationship between forest decline and precipitation changes in Ilam Province | ||
| نویسندگان [English] | ||
| Ghasem Azizi1؛ Morteza Miri2؛ Hossein Mohammadi3؛ Mehdi Pourhashemi4 | ||
| 1Associate Prof., Faculty of Geography, University of Tehran, Tehran, Iran | ||
| 2Ph.D. Student, Faculty of Geography, University of Tehran, Tehran, Iran | ||
| 3Prof., Faculty of Geography, University of Tehran, Tehran, Iran | ||
| 4Associate Prof., Research Institute of Forests and Rangelands, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran | ||
| چکیده [English] | ||
| Oak decline phenomenon recently led to considerable dieback within Zagros forests. This study was designed to assess the temporal trends of changes in forest cover of the Ilam province in association with precipitation variations during a 14-year period (2000-2013). To this aim remote sensing and GIS techniques were used. The remote sensing data included 16-day NDVI products of MODIS data as well as Google-Earth archive and the related control points. Additionally climatic data from synoptic stations, GPCC long-term data and TRMM rainfall data were applied. The optimal number of land cover and forest classes was defined by means of an unsupervised ISODATA method and mean and minimum divergence separation indexes. The result indicated 35 and 30 land cover classes to be appropriate for annual and long-term assessments, respectively. Spectral graph revealed a growth period from mid-February to early-May within Ilam forests. NDVI trend revealed the first significant reduction in forest cover in 2005 and the second one in 2008, which was followed by a descending trend in forest cover for the last 3-years of the investigated 14-year period. The data from ground stations and rainfall grid point indicated negative annual and monthly rainfall trends. The trend was significant within forests in 90% and 95% confidence levels. The peak of the declining precipitation trend was observed in the beginning of growth season in March. Correlating the NDVI with and precipitation trend revealed significant reduction of annual precipitation and drought stress during the growth season are particularly responsible for considerable amounts of forest dieback and chlorophyll decline within forests of Ilam. | ||
| کلیدواژه‌ها [English] | ||
| Separability, oak decline, GPCC, satellite TRAA, Satellite TRMM | ||
| مراجع | ||
|
- Anonymous, 2011. National project on prevention and control of oak decline in Zagros forests. Published by Forests, Range and Watershed Management Organization, Tehran, 52p (In Persian). - Arend, M., Brem, A., Kuster, T.M. and Gunthardt, M.S., 2012. Seasonal photosynthetic responses of European oaks to drought and elevated daytime temperature. Plant Biology, 15(1): 169-176. - Bravo, F., LeMay, V., Jandl, R. and Gadow, K., 2008. Managing Forest Ecosystems: The Challenge of Climate Change. Springer, 333p. - Bugmann, H., Brang, P., Elkin, C., Henne, P., Jakoby, O., Lévesque, M., Lischke, H., Psomas, A., Rigling, A., Wermelinger, B., Zimmermann, N.E., 2014. Climate change impacts on tree species, forest properties, and ecosystem services: 79-88. In: Raible, C.C.; Strassmann, K.M. (Eds.) CH2014-Impacts, Toward Quantitative Scenarios of Climate Change Impacts in Switzerland, Bern: OCCR, FOEN, MeteoSwiss, C2SM, Agroscope, and ProClim. - Dewan, A.M. and Yamaguchi, Y., 2009. Using remote sensing and GIS to detect and monitor land use and land cover change in Dhaka Metropolitan of Bangladesh. Environmental Monitoring and Assessment, 150: 237-249.
- Hamzehpour, M., Kia-daliri, H. and Bordbar, K., 2012. Preliminary study of manna oak (Quercus brantii Lindl.) tree decline in Dashte-Barm of Kazeroon, Fars province. Iranian Journal of Forest and Poplar Research, 19(2): 352-363 (In Persian). - Hanson, P.J. and Weltzin, J.F., 2000. Drought disturbance from climate change: response of United States forests. The Science of the Total Environment, 262: 205-22. - Hosseini, A., Hosseini, S.M., Rahmani, A. and Azadfar, D., 2013. Comparison between two oak stands (healthy and affected by oak decline) in respect to characteristics of competitive environments at Ilam province. Iranian Journal of Forest and Poplar Research, 21(4): 606-616 (In Persian). - Jafari, M.R., Hosseinzadeh, J., Pourhashemi, M., Norouzi, A.A., Mirakhorlou, Kh. and Mohammadpour, M., 2014. Identification and zoning of forest stands affected by oak decline using GIS & RS in Ilam Province. Final Report of Research Project, Published by Research Institute of Forests and Rangelands, 48p (In Persian). - Krahwinkler, P. and Rossmann, J., 2010. Tree species classification based on the analysis of hyperspectral remote sensing data. 30th EARSeL Symposium: Remote Sensing for Science, Education and Culture, Paris, 207p. - Mapfumo, B., Murwira, A., Masocha, M. and Andriani, R., 2014. Monitoring and evaluating the impacts of subtle deforestation on tree diversity in savanna woodlands. International Journal of Research in Agriculture and Food Sciences, 1(5): 2311-2476. - Mas, J.F., Puig, H., Palacio, J.L. and Sosa-Lopel, A., 2004. Modeling deforestation using GIS and Artificial Neural Networks. Environmental Modeling & Software, 19: 461-471. - Nguyen,T.T.H., 2013. Earth observation for rice crop monitoring and yield estimation: Application of satellite data and physically based models to the Mekong Delta. Ph.D. thesis, Faculty of Geoinformation Science and Earth Observation, University of Twente, Netherlands, 49p. - Papoli Yazdi, M. and Fathnia, A., 2007. Relationships between humans and oak. Journal of Geography Education, 20(1): 7-17 (In Persian). - Parma, R. and Shataee Jouybari, Sh., 2010. Impact of physiographic and human factors on crown cover and diversity of woody species in the Zagros forests (Case study: Ghalajeh forests, Kermanshah province). Iranian Journal of Forest and Poplar Research, 4(42): 539-555 (In Persian). - Pietrzyk, P.J. and Lindenbergh, R.C., 2014. Detection of harvested trees in forests from repeated high density airborne laser scanning, ISPRS Annals of the Photogrammetry. Remote Sensing and Spatial Information Sciences, 2(5): 275-280. - Ryan, M.G., Vose, J.M. and Weed, A., 2012. Effects of climatic variability and change on forest ecosystems: A comprehensive science synthesis for the U.S. forest sector. Chapter 2: Effects of Climatic Variability and Change. General Technical Report PNW-GTR-870, Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station, 5p. - Sakthivel, R., Manivel, M., Jawahar Raj, N., Pugalanthi, V., Ravichandran, N. and Vijay, D.A., 2010. Remote sensing and GIS based forest cover change detection study in Kalrayan hills, Tamil Nadu. Journal of Environmental Biology, 3(5): 737-747. - Shen, Z., Gang, F., Chengqun, Y., Sun, W. and Zhang, X., 2014. Relationship between the growing season maximum enhanced vegetation index and climatic factors on the Tibetan Plateau. Remote Sensing, 6: 6765-6789. - Sun, J., Cheng, G., Li, W., Sha, Y. and Yang, Y., 2013. On the variation of NDVI with the principal climatic elements in the Tibetan Plateau. Remote Sensing, 5: 1894-191. - Tou, J.T. and Gonzalez, R.C., 1974. Pattern Recognition Principles Massachusetts: Reading, Advance Book Program. Addision-Wedley Publishing Company. - Weber, P., Bugmann, H., Fonti, P. and Rigling, A., 2008. Using a retrospective dynamic com-petition index to reconstruct forest succession. Forest Ecology and Management, 254: 96-106. - Hussin, Y.A. and Bijker, W., 2000. Inventory of remote sensing applications in forestry for sustainable management. ISPRS 2000 Congress: Geoinformation for All, Amsterdam, the Netherlands, 16-23 July, pp. 575-587. - Zangiabadi, S., Ahmadimoghadam, A. and Naseri, F., 2011. Forest classification using IRS satellite data. World Applied Sciences Journal, 15: 1409-1413. - Zebardast, L., Jafari, H.R., Badehian, Z. and Ashegh Moalla, M., 2011. Assessment of the trend of changes in land cover of Arasbaran protected area using satellite images of 2002, 2006 and 2008. Environmental Researches, 1: 23-33 (In Persian). - Zhao, X., Xu, P., Zhou, T., Li, Q. and Wu, D., 2013. Distribution and variation of forests in China from 2001 to 2011: A study based on remotely sensed data. Forests, 4: 632-649. | ||
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