1991 Volume 35 Pages 161-166
The objectives of this paper are (1) to show longitudinal variation of channel geometry and flow resistance of mountain rivers, (2) to incorporate this variation into distributed rainfall-runoff model already developed and (3) to apply this model to predict flood hydrographs. In two experimental basins, 28 cross-sections are surveyed for channel geometry, slope and discharge at that time. From this data, Manning's n is computed. Both channel width and Manning's n show a longitudinal variation, and are related to drainage area used as longitudinal index in this study. By taking this variation into account, the model reproduces the measured hydrographs with a good correspondance both in experimental basins and in large basins.