石狩川の土砂流出に関する研究

抄録

It is an important subject to evaluate sediment transport bubfet in river management works. In this paper sediment transport output from the Ishikari River is investigated as primitive example for this subject. Relationship between turbidity data and suspend sediment concentration data is investigated and a formula to evaluate wash load transport rate is proposed. Using the daily discharge data of the past 20 yeas, the annual sediment runoff from the Ishikari River mouth is calculated. The annual runoff of the bed material is also calculated by a numerical model for bed load and suspended load transport, bed deformation and grain size distribution of bed material. The results of wash load runoff and bed material load runoff are compared and it is found that wash load runoff can be explained as a part of bed material load.