Determining Daily Variations Of River Flood Plains In The Southern Buffer Zone Of Urmia Lake In 2010

This study investigates the Buffer area of main southern streams of the lake Urmia including Zarinehrood, Gadarchai and Mahabadchai rivers as south western streams, Zarinerood and Mardoogh chaii as southern streams and ghalee chaii and Soofi chaii as south eastern streams. Buffer zone area is located between maximum and daily extent of Lake Urmia that is selected as the study area. The study is done based on 143 days of the year 2010 that buffer area and southern streams are not cloudy. Using available data from Bonab meteorological hydrometry stations, changes of Buffer area were analyzed. The aim of this study is Determining of Daily Variations of river flood plains in the southern buffer zone of Uremia Lake. Temporal Analysis of flood plains showed that from late May, most southern feeder streams got dried. Also, the analysis of time-discharge charts have shown that similar to dried feeder streams, from late May, the registered discharge of terminal hydrometry stations got zero. Also, analysis of discharge-time graphs show that prportionable to dried flood plains, registered discharge in tail-end stations became zero. Results of investigation of daily precipitaton show that effective rainfall occurs in the first 135 days which means from middle Bahman to middle Khordad and daily precipitation decrease prportionable to discharge and floodplain in the summer. Based of the study findings southern stream that includes Zarinerood and Mardooghchaii rivers, is more stable than two other western and eastern streams and this branch is connected to the lake in all 143 days.