Document Type : Research Paper
Authors
1 Department of Geography, University of Shahid Beheshti
2 Associate Professor, Department of Geography, Shahid Beheshti University
3 Graduate Student, Shahid Beheshti University geomorphology
Abstract
Flood is a natural phenomenon, which has been experienced by human being from very old times. In Iran, due to its very large area, several climates, time and local density of precipitation in most watersheds, there are many great floods in most areas of the country. In this study, run-off coefficient, maximum debit of flood, identifying the factors and elements that are effective on floodiness, and zoning of the area of Mardaq Chai watershed based on its flood bearing are analyzed. The curve number method of the Soil Conservation Service of America, which proposed a method to determine surplus precipitation in 1954, was used for this watershed. This is the most usual method for prediction of run-off volume. To do this, firstly, the needed data and information including the statistical situation of the area climates and satellite images were gathered and entered to the GIS data system. Compiling these data and information by the SCS method and the CN of the watershed, the infiltration level and run-off volume were prepared. Finally, the zoning map of the annual flooding potential of the area with different reoccurring periods were produced using weighting model and compiling the area precipitation, hydrological groups of soil, slope level, land use, etc. Iran, due to its very large area, several climates, and time and local density of precipitation in most watersheds, faces with many great floods in most areas.
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