To achieve relatively better compatibilities between the models and the study areas, the calibrations and validations of the TOPMODEL and TOPX were performed in the study watersheds. Using the data of the first three years of the corresponding study periods, TOPMODEL and TOPX were calibrated with the method of trial-and-error. The model validation for each study watershed was investigated with the data of the remaining two or three years of the corresponding study periods. The results of the calibrations and validations showed adaptive applications for TOPX in YLX and WJB, and for TOPMODEL in HQ. The calibrated parameters for TOPX and TOPMODEL are listed in Table 4.