نشریه جغرافیا و برنامهریزی (Oct 2014)
Investigation on Aji-Chay River Meander Changes on Flood Plain
Abstract
Meanders, as a interesting water flow patterns in nature, is giving dynamic to courses of rivers.Creation of curvature on courses of rivers is give enough energy for migrate active channel on floodplain. This migration is main reason for many geomorphology in events is floodplains and at final is changing the floodplain pattern .These changing is created many problems for man-made structures that is constructed at bank or on courses of rivers. Aji-Chay River, as a typical meander is migrate on floodplain by creation curvature on its course (is situated at 37° 58′ to 38° 07′ N and from 46° 15′ to 47 °45′ W). In this article is analyzed and estimated migration rate, migration potential and time of migration ,by use of experimental methods, by satellite and areal images In this study rely on parameters of meanders, as bind and width of river corridor is estimated by use of W methods and ∆t, R/W calculation, in order to investigation on capability of rivers for movement .In this study also is estimated time of active channel migration on floodplain by use of valid methods .The results of this study show that active channel of Aji-Chay repeatedly movement on floodplain in during time and because these movement and changing and bank erosion, is flatten the floodplain .In part of Aji-Chay course time period for completed a cycle of migration is from 1 to over 5 years. This period is vary in many parts of river course. The results of this study also suggested that sinuosity rate at length of Aji-Chay course is changed in during time and old race of water flow is evidence these changes.
