Vol.5-1
 
千曲川水系の変遷に伴う流出形態の変化に関する研究
Studies on the Change of Run-off Trend Caused by the Transition of Chikuma Basin
荒木 正夫* ・ 富所 五郎* ・ 寒川 典昭* ・ 松岡 保正**
Masao ARAKI*, Goro TOMIDOKORO*, Noriaki SOGAWA* and Yasumasa MATUOKA**

 

Abstract
 On the froods in the Chikuma, the relation between basin development and run-off trend is described on process of time.
 Firstly, tha 1st principal component obtaied from an principal component analysis using five factors of the basin development is adopted as a basin development index, and it becomes clear that the correlation between the index amd run-off percentage has existed obviously.
 Seconly, it is proved that the 1st run-off percentage has increased gradually, and the time of flood concentration has reduced according to the run-off analysis using a storage function model.
 Finally, it is proved that the inundation damages have translated gradually from the upper basin to the middle or the lower one with development, and it is found that the retarding volume contributes to the reduction of food run-off discharge.


* 信州大学工学部
Faculty of Engineering, Shinshu Univ.
** 長野工業高等専門学校
Nagano National College of Technology


日本自然災害学会