Investigation of Vertical Distribution of Dust Storms Sediment Flux in Sistan Region

Prolonged drought has resulted in severe wind erosion and dust storms in Sistan region. Investigating wind erosion and dust storms is essential to control these Phenomena. Investigating the vertical distribution of aeolian sediment flux is important for assessing sediment transport, validating wind erosion models, and understanding the mechanism of particle movement. In this study, six dust storm events and vertical distribution of sediment flux within these events were studied during a period of four months of 2018 in Sistan. Recorded diurnal wind speed, visibility, and PM10 data at Zabol meteorological station were obtained for the study period. To obtain a vertical distribution of sediment flux, seven sediment samplers were installed at seven heights from 20- to 700 cm in the Niatak area of Sistan. Results indicated that the six dust storm events have been recognized to be severe, because wind speeds of 16-19 m/s have blown in a long period of the events, visibility was 10 increased >2000 µg m-3 and sometimes >8000| µg m-3. The greatest sediment flux was observed in events 3 and 4 and least in event 3. Sediment flux was attributed to wind speed and durian of blowing wind speed. Sediment flux is greater in higher wind speeds and long events. There was a close relationship between recorded PM10 at Zabol station and collected sediment. There was a negative and power correlation between sediment flux and height.