| dc.description.abstract | Hypsometric integral of drainage basin can be used to infer the landscape evolution stage, but caution must be taken that it is significantly influenced by scale dependency. Locating at oblique convergence boundary, mountain belt of Taiwan results in different phases of geomorphological development, which is suitable for illustrating different hypsometric characteristics of drainage basins. In this study we used 10meter-DEM which reduced from 5meter-DEM to process elevation analysis. We choose erosion and transportation dominating watersheds for study, so that the effect of deposition along channels and flat land can be minimized. The raised new small scale analytical units we call it erosion-dominant unit. In this condition, the hypsometric analysis can carry out under the original assumption of erosion dominating background.
According to previous studies, the northern, central, and southern segments of Taiwan mountain belt are differentiated as collapsing mountain, mature mountain, and growing mountain, respectively. To investigate scale dependency, we select three representative drainage basins from each segment of the western mountain belt and do detailed analysis. At last, we pick two drainage basins from each segment and do analysis in the most representative scale, to discuss distinct hypsometric characteristics through different stage in mountain belt. In addition, I compare my result with the result of previous studies in western Central mountain range.
The sub-basin scale, which SWCB used, with area between 100 and 200 square kilometers, can be used to distinguish different mountain evolution stages, and to support Ohmori′s cycle of hypsometric curve. In addition, taking erosion-dominant unit as the new small scale analytical unit, its geological signification is more conforming to original hypothesis of drainage basin evolution cycle. With this scale, we could recognize the details of landscape evolution stage at each drainage basin through the use of hypsometric integral value distribution. | en_US |