The use of frequency ratio method in erosion susceptibility analysis: the case of Selendi River Basin (Manisa)

Erosion susceptibility analysis done by Geographic Information Systems are made using prepared or independent erosion models. Recently, erosion susceptibility analyses made by independent erosion models in which parameter numbers and analysis methods can be freely selected by users, have raised. There are various methods used in creating independent erosion model. One of them is frequency ratio. Frequency ratio is totally statistical method and is usually used in landslide susceptibility studies. It is possible to make landslide susceptibility analysis because it is easier to create an inventory by defining landslide on area or via satellite imaging, even by topographic map. In this study, it is aimed to make an erosion susceptibility analysis which is totally statistical, by using frequency ratio. This measurement and defining process is much harder than landslide. Therefore, an inventory is prepared by using signs that show erosion is severe in the land. In research area, a database is created by using topographic, geologic, hydrographical, environmental and climatic parameters which are tought to be effecting erosion. Finally, an erosion susceptibility analysis for Selendi River Basin through the frequency ratio method. In this method, the parameters that is tought to be effecting the erosion in the area and the erosion surfaces inventory are assessed together. Using of a completely statistical method such as frequency ratio enables users to make an assessment which is objective. Also, using these methods may inhibit errors originating from users, on the contrary of subjective parameter weighting which is based on specialist opinion