نوع مقاله : علمی - پژوهشی

نویسندگان

1 استاد گروه جغرافیای طبیعی، دانشکده علوم زمین، دانشگاه شهید بهشتی، تهران

2 دانشجوی دکتری ژئومورفولوژی، دانشکده علوم زمین، دانشگاه شهید بهشتی، تهران

چکیده

تالاب‌ها باقیمانده دریاچه‌های بارانی هستند که در اثر پس‌روی یخچال‌ها در اواخر عصر پلئیستوسن و غلبه شرایط گرم و توسعه رسوبات تبخیری عصر هولوسن به وجود آمده‌اند. دریاچه‌های کویری، پلایاها و لندفرم‌های مشابه آن در بسیاری از مناطق خشک و نیمه‌خشک، در‌ نتیجه فعالیت‌های انسانی دچار اختلال و آشفتگی شدند. در حال‌حاضر، برداشت منابع معدنی و در نتیجه تخریب سطوح پلایا، همچنین بی‌نظمی در آب ورودی، موجب تحول جدیدی در این ژئوسیستم‌ها شده است. این تحولات زمینه دگرگونی در میکروفرم‌های این مناطق را فراهم آورده، به‌طوری‌که می‌توان این دگرگونی را شاهدی بر بی‌نظمی یا آشوب در سیستم شکل‌زایی حاضر و گذار آن به سیستم دیگر دانست که به وسیله هندسه فرکتالی قابل بررسی است. در این تحقیق، بررسی‌های میدانی درباره وضعیت پلایای گاوخونی در جنوب شرق اصفهان و تغییرات ایجاد‌شده در میکروفرم‌های آن در زمستان 1393در منطقه انجام شد که طی آن ابعاد 109 ترک گلی در زون مرطوب پلایای گاوخونی بررسی شد و از بین آنها ابعاد61 ترک گلی که به‌خوبی توسعه یافته بودند، محاسبه شدند. با بررسی هندسی فرکتالی محیط-مساحت در میکروفرم‌ها، میزان آشفتگی آنها بررسی شد. DAP به‌دست‌آمده مقادیری بین 27/1 تا 44/1 را نشان داد، که گویای آشفتگی در منطقه است. نمودار لگاریتمی نیز ارتباط خطی بین لگاریتم محیط و مساحت فرم‌های مورد نظر را آشکار ساخت، به‌طوری‌که ضریب همبستگی R2 به‌دست‌آمده بزرگتر از 96/0 بود. افزایش آشفتگی در منطقه، حاکی از تحول سیستم شکل‌زایی و تبدیل تالاب به اکوسیستمی جدید بوده است که می‌تواند مخاطرات جدی را در این منطقه به همراه داشته باشد.

کلیدواژه‌ها

عنوان مقاله [English]

A Morphological Approach to Strategic Management of Wetlands and Playas (Case Study: Gavkhuni Playa)

نویسندگان [English]

  • Manijeh Ghahroudi Tali 1
  • Ladan Khedri Gharibvand 2

1 Professor, Department of PhysicalGeography, Faculty of Earth Sciences, University of Shahid Beheshti, Tehran

2 Ph.D. Student of Geomorphology, Faculty of Earth Sciences, University of Shahid Beheshti, Tehran

چکیده [English]

Wetlands are the remnants of pluvial lakes which have evolved following the retreat of glaciers in the late Pleistocene era and have overcome the hot conditions and the development of evaporative deposits in the Holocene era. Most arid and semi-arid areas, desert lakes, playas and similar landforms have been disturbed as a result of human activities. Recently, mineral extraction prompts destruction of the playa surfaces and irregularities in the incoming water in order to create a new evolution in these geo-systems. This new evolution provides a suitable situation to change the micro-landforms, and these irregularities or turbulences in geodynamic systems are the best evidence for converting them to other systems and, also, they can be studied by fractal geometry. In this study field studies were conducted in the winter of 2015 in order to examine the situation of the Gavkhuni playa southeastern Isfahan Province and the changes in micro-landforms and, in these, 109 mud cracks in the wetland zone of Gavkhuni playa were examined. Among them, 61 well developed mud cracks were used in the calculations. By using the fractal geometry perimeter-area model on these micro-landforms, their turbulence could be examined, and the DAP, derived from the fractal model, was valued at between 1/27 - 1/44; this expresses the confusion and irregularities in the micro-landforms of that region. The logarithmic graph of the fractal model showed a linear relationship between the log of perimeter and the log of area on that micro landform and, so, the correlation coefficient R2 is greater than 0.96. Increasing chaos in the Gavkhuni playa shows the evolution in the geodynamic system and its transformation into a new ecosystem that it can yield to produce serious risks in this area.

کلیدواژه‌ها [English]

  • Gavkhuni
  • Micro-landform
  • Fractal
  • Mud crack

Asgari A. Playa and evaluate mineral potential in the khorasan province (with attitude specifically, lithium). National Geoscience Database of Iran (NGDIR); 1999. p.11.[In Persian

Gill T E. Eolian sediments generated by

anthropogenic disturbance of playas: human

impacts on the geomorphic system and

geomorphic impacts on the human system .

Geomorphology Journal; 1996; 17(1-3): 207.

Ghahroudi Tali M. Comparative study of climate

change and geomorphology in Playa Meighan .

Shahid Beheshti University of Tehran, Iran .

Research project; 2012. p43. [In Persian

Ghahroudi Tali M, Mirzakhani B, Askari A. The

phenomenon of desertification in Iran wetlands ,

Case Study: Meighan wetlands. Geography and

environmental hazards Journal; 2012; 4: 22. [In

Persian

Ghahroudi Tali M, Derafshi K. The study of

chaos in the flood risk pattern of Tehran. Environmental Spatial Analysis Disaster Journal; 2015; 7 (2):1-16. [In Persian

Martino G D, Riccio D. A Novel Approach for

Disaster Monitoring: Fractal Models and Tools. IEEE Transactions on Geoscience and Remote Sensing Journal; 2007; 45(6):12.

Mandelbrot, B B.The fractal geometry of nature

(updated and augmented edition). Freeman, New

York; 1983.p.468.

Malamud B D, Turcotte D L, Guzzetti F,

Reichenbach P. Landslide inventories and their

statistical properties. Earth Surface Processes and

Landforms Journal; 2006; 29 (6): 687.

Lovejoy S. Area–perimeter relation for rain and cloud areas. Science Journal; 1982; 216(4542):185-187.

Mandelbrot B B, Passoja D E, Paullay A J. Fractal character of fracture surfaces of metals. Nature Journal; 1984; 308 (5961): 721.

Goodchild M F. Lake on fractal surfaces: a null hypothesis for lake-rich landscapes. Math Geol Journal; 1988; 20(6):15–630.

Lovejoy S, Schertzer D. Multifractal analysis techniques and the rain and cloud fields .From 10–3 Dordrech; 1991.

Cheng Q, Russell H, Sharpe D, Kenny F, Qin P. GIS-based statistical and fractal / multifractal analysis of surface stream patterns in the Oak Ridge’s Moraine. Computer Geoscience Journal; 2001; 27(5):513-526.

Ramesht M H. Hazards Tracing Hoz-e Soltan

Playa through Investigating Chaos in Microlandforms. Geography and Development Iranian Journal; 2003; 1 (1):13-36. [In Persian

Ghahroudi Tali M, Alinoori K. Hazards Tracing

Hoz-e Soltan Playa through Investigating Chaos

in Micro-landforms. Iranian Journal of Hazards

Science; 2015; 1 (2):241-252. [In Persian

Ghahroudi Tali M, khedri gharibvand L. The Investigation of Chaos in Micro-Landforms in

the Gavkhooni Everglade. Geodynamics Research International Bulletin (GRIB) Journal; 2014; 2 (3):44-51.

Vandenberge D R, Brandon T L, Duncan J M. Triaxial Tests on Compacted Clays for Consolidated Undrained Conditions. Geotechnical Testing Journal; 2014; 37: 4.

Karam A. Chaos theory, fractal and nonlinear systems in geomorphology. Natural geography journal; 2010; 3(8):72. [In Persian

Cheng Q. Multifractal modeling and spatial analysis with GIS: Gold potential estimation in the Mitchel-Sulphurets area, Northwestern British Columbia. Ph.D.: University of Ottawa, Ottawa; 1994.p.268.

Salami H, Naderi H. Technical report assessing the sources and uses of water in the catchment area of the river. Iran Water Resources Research journal; 2007 ; 2(1):74. [In Persian

Ebrahimzadeh E, Karimi J. Analysis of the planning and development of ecotourism in wetland basin Gavkhoni using bioclimatic indices. Geography and planning journal; 2012; 16(39):4. [In Persian

Bateni F, Fakheran S, Soffianian A. Assessment of land cover changes & water quality changes in the Zayandehroud River Basin between 1997–2008. Environmental Monitoring and Assessment Journal; 2013; 185(8): 117.

Allahdadian L, Khoshakhlagh R. Economic Water Reallocation in the Zayande Rood Basin (Iran) Among Different Uses via Designed Software. International Journal of Academic Research in Economics and Management Sciences Journal; 2013; 2(6): 1

Soltani S. Gavkhoni determines wetland water rights (section Limnology). Environmental Protection Agency Isfahan province. Research project; 2010; 1. [In Persian

NASA (2012), Satellite image of Gavkhuni Area. Scene 135-3.

Najari H. Wetland of International Gavkhuni of Isfahan. Environmental Protection Agency Isfahan province; 2014: 155. [In Persian

Pakzad H.R, Fayazi F. Sedimentology and Stratigraphic Sequence of The Gavkhuni Playa Lake, SE Esfahan, Iran. Carbonates and Evaporites Journal; 2007; 22(2):93.

Cheng Q .The Perimeter–Area Fractal Model and Its Application to Geology. Math Geol Journal; 1995; 27(1):69.

Wang Z, Cheng Q, Cao L et al. Fractal modelling of the microstructure property of quartz mylonite during deformation process. Math Geol Journal; 2006; 39(1):53.