11:00 〜 11:15
[HGM03-07] 梓川上流，上高地における流路変動と元の河床微地形との関係
キーワード：網状河川、流路変動、微地形、河床、上高地、梓川
The purpose of this study is to discuss relationships between channel migration process and micro landforms on riverbed in Kamikochi region, the upper Azusa River, central Japan. Based on ground surveying geomorphological maps of the observation area which were made every year in summer season. Interval shooting cameras took photographs every 15 or 20 minutes interval between 2011 and 2016. Also section surveying performed every autumn season.
During the Bai-u rainy season in 2013 and 2017 the major channel migrations occurred. On that days daily rain fall were over 140 mm. Those heavy rain events caused the bankfull discharge and the major channel migration. When the channel migration occurred, without gradual lateral move of channels, former channels were buried and/or narrowed and new main channels excavated tracing small channels and/or small ditches which had existed just before channel migration.
During the Bai-u rainy season in 2013 and 2017 the major channel migrations occurred. On that days daily rain fall were over 140 mm. Those heavy rain events caused the bankfull discharge and the major channel migration. When the channel migration occurred, without gradual lateral move of channels, former channels were buried and/or narrowed and new main channels excavated tracing small channels and/or small ditches which had existed just before channel migration.