MORPHODYNAMIC ANLYSIS OF WIND FACES USING SPATIAL SAND ROSE MODEL IN ZABOL AND ZAHAK REGION, IRAN

Abstract

The majority of Iran’s area is covered by arid and semiarid climates. In these areas, wind causes more erosion compared to water. Therefore, determination of wind characteristics especially its velocity is very important. One of the simplest methods that can supply researchers with the origin of wind erosion in the shortest time is synthesizing sand rose model and interpretation of aerial photographs or satellite images. The main purpose of this research was to find the relationship of soil drift potential. Sand rose is a diagram that shows not only the direction of wind transportation but also the wind erosion potential. Using a formula, soil ablation potentials were determined for drawing sand rose. A computer program was used to simplify and speed up the computations and increase the accuracy. Two stations in Sistan – Balochestan province, namely Zabaol and Zahak were selected. These two stations are located on flat lands and are naturally faced with higher wind erosions. The two stations are faced with the 120 days winds of Sistan and have very high drift potential. The results of this study show a south- southeast direction of drift potential, which exactly matches the direction of 120 days Sistan winds. Interpretation of aerial photographs and satellite images confirmed the sand rose study results because most of sand dunes showed a south – southeast direction of wind. Considering the location of sand dunes result drift direction, and the distance that sand can be transported, the locations of sand ablation was identified to be waterways and pediments of Sistan and also agricultural lands around Zabaol and zahak.