cluster analysis for determination of the hydrologic homogeneitym, assessment with discriminant analysis and andrew curves in karkheh basin

usually sufficient number of data of the hydrological variables is not available for frequency analysis. therefore, through the method of regional analysis the sample data are used for fitting with probability distributions and for probability theories regarding statistical population. the results of regional analysis would be valid, in case of the study region to be homogeneous in the view of climatic, physiographical factors and soil characteristics. in this study, using 16 hydrologic characteristics from 41 hydrometry stations in karkheh basin, factoranalysis and choosing the independent physiographical factors by cluster method, the homogeneous region delineation by discriminant analysis and andrew curves have been used. five factors of diameter of equivalent circle, mean elevation, mean slope and bifurcation ratio of basin, distinguished as independent physiographical factors. also classification with cluster analysis by considering 10 for euclidean distance and ward's method, six basins of holian (seymareh), tang-sazbon, cham-jab, jeloghir (majin), cham-gaz and pay-pol were there. consequently, the region was grouped into two sub-groups of 3s and six catchments