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
کلیدواژهها
عنوان مقاله [English]
نویسندگان [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]