Estimation of attached-algae removal amount in gravel-river based on field observation of spatio-temporal distribution of sediment transport

2015 Fiscal Year Final Research Report

• Project/Area Number: 26820205
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Hydraulic engineering
• Research Institution: Hiroshima University
• Principal Investigator: Tsubaki Ryota 広島大学, 工学(系)研究科(研究院), 助教 (80432566)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: 洪水 / フラッシュ放流 / 土砂移動 / ハイドロフォン / 付着藻類

Outline of Final Research Achievements

A method to monitor spatio-temporal distribution of graded sediment transport during small/medium flood events was developed. This method was utilized to understand the contribution of sediment transport on attached-algae removal in a section of gravel-bed river during flushing flow events. It was found that transport of medium-sized gravel (d=0.5 to 3 cm) is quite limited even if there is supply from upstream. This is because medium-sized gravel has been trapped in the dents formed between the larger gravels and cobbles. This implies that the contribution of gravel transport during small/medium floods in the focused river section on the attached-algae removal is negligible.

Free Research Field

河川工学