مدل بندي منطقه اي سيلاب در حوضه آبخيز جنوب غربي اردستان

Flood regional modeling in southwest watershed of Ardestan city

Flood occurrence in different regions of our country has urged as to study the reasons of flood occurrence and intensification. Due to particular features of climate, geomorphologic, physiographic and land use in arid and semi arid region, the effects of flood have higher extension and damage in such areas. In this study, the effective factors on flood in different watersheds in southwest of Ardestan with the area of 316.5 square kilometere were determined using GIS techniques, and field study. Then, using statistical methods such as factor analysis and cluster analysis, regression model which suggests mathematical relationships between flood factors and flood intensification as independent variables related to different return periods as dependent variables, was developed. Results show that the watershed area is the most important factor on flood peak discharge. Among climatic factors, rainfall intensity with 200-year return period was found to be effective on flood peak discharge which is due to very high return period of rainfall intensity.