open access

https://hdl.handle.net/2115/39723

Geomorphic impacts of tributary fans on mainstem fluvial system in Shukushubetsu River Catchment, northern Japan

英語

2009-11-02

Tributary fan is a major geomorphic component and can exert significant effects on channel processes along the mainstem. In mountainous regions, numerous tributaries develop fans with various morphology and related vegetation structure. Size and four distinct patterns of vegetation structure of fans were used to evaluate the geomorphic impacts. Channel characteristics of mainstem at each confluence were also examined to understand connectivity of tributary fans with mainstem channel. Catchment size of tributaries relative to the mainstem is a major factor to control tributary fan size, while this efficiency was much differ among the four patterns. In the gorge segment, fan areas were dominated by younger features. In the upper floodplain segment, on the contrary, features of fans were varied from younger to older. Results indicated that geomorphic impacts of tributary fans were affected by not only relative size of tributary catchment but also discontinuous changes in channel characteristics of mainstem.

会議発表資料

Not Applicable (or Unknown)