Relationships between landform changes in the riverbed and rainfall in 2011 in the upper reaches of the River Azusa, Central Japan

Abstract

This study aims to discuss the relationships between the landform changes and rainfall in the upper reaches of the R.Azusa. The geomorphological maps, photographs taken in every 10 minute and rainfall data from AMeDAS in Kamikochi were used for discussions. In 2011 heavy rainfall events occurred on 10 May (before the Baiu rainy season), 23 June (in the Baiu) and 20 September (by typhoon). Daily rainfall was recorded over 120mm. The landform changed in the May or June event. Although flooding water covered large extent of the riverbed during the September event, only minor landform change was recorded.