Hydrological Delineation of Homogeneous Regions in Tunisia

An innovative method for hydrological delineation of homogeneous regions in Tunisia is presented. The approach considered is based on the shape of the empirical Cumulative Distribution Function (CDF) and similarities of physiographic and climatic characteristics. Based on annual flood data of 49 hydrometric stations, with record lengths ranging from 10 to 100 years, spatial trends of the shape of the CDF were employed to identify mixed processes in the flood series. This resulted in dividing the study area into mixture and non-mixture zones. Hydrologic homogeneity of the delineated regions was tested by L (Linear) moment-based statistical tests. The exercise resulted in dividing Tunisia into 10 homogeneous regions, where mixed flood processes haven't been recognized.