RUNOFF PROCESS, SEDIMENT YIELD AND TRANSPORT IN A MOUNTAIN WATERSHED (18)

The study of runoff process, sediment yield and transport have been performedsince 1966 in the Ashiaraidani creek (7.2 km2) of the Jintsu river.In this study, three problems are discussed;(1) The relation between sediment yield and rainfall, slope grade are examined, to clarify the processes of sediment yield in various slopes, taking seasonalvariations as well as site conditions into accounts. (2) The relation betweensediment runoff and sediment storage in the steep channel with pools wereinvestigated in the Hirudani creek (0.85 km2). (3) The occurrence of debris flow wereinvestigated with attention forcused on rainfall intensity and infiltration in theShiramizudani creek (2.1 km2).