The Study and Estimate of Floods in meandering river channels according to changes the channel bending (Case Study: Aji-Chay river in the North West of Iran)

Introduction Active Mending Rivers are the most dynamic and sensitive parts of the fluvial landscapes. Meandering rivers suffer a large Geomorphic changes during the annual flood events. Based on large flood evidences، reconstruction of the channel bed migration will be possible، which is use for Evaluation of future Evaluation and flood risk assessment in the flood plain areas. The morphological evolution of river meanders has been analysed by many authors and various pattern and models has been suggested (eg. Alfredo 2010، chen 2006، Hook 2008، Borisova 2006). Many researchers have examined the morphological impacts of floods and some studies of channel instability have combined time scales، examined the combined effects of flood phases and demonstrated temporal and spatial variability of stream stability. There are many meandering rivers passing from flood Palin areas in Iran which are studied by Iranian researchers (eg. Bayati Khatibi 2012، Rezaei moghadam and khoshdel 2009، Yamani 2008، Jahadi Toroghi and Hosseinzadeh 2012). The purpose of this paper is to demonstrate of active channel changes of Aji-Chay River over the time and assessment of flood occurrence potential based on disptacement of bending river course.