Budget Amount *help |
¥5,330,000 (Direct Cost: ¥4,100,000、Indirect Cost: ¥1,230,000)
Fiscal Year 2013: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000)
Fiscal Year 2012: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
Fiscal Year 2011: ¥2,470,000 (Direct Cost: ¥1,900,000、Indirect Cost: ¥570,000)
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Research Abstract |
Recently, riparian vegetation has been extremely increasing and alternate bars covered with much vegetation can be seen as one of typical landscape in gravel-bed rivers. This situation brings about forestation in river which reduces the capacity of flood discharge and affects channel morphology by increasing of local roughness. This study aims to propose an effective method for restoration in such deteriorated gravel rivers by flood disturbance. The bed excavation over the vegetated gravel bar in the segment-1 zone of Watarase River was conducted for the restriction of growth of riverine trees and the recovery of crooked low-water channel caused by leading flash flood flow over forested bars. As results of the field survey and the numerical hydraulic simulation, it was confirmed that induced flood disturbance due to bed excavation on a stable forested gravel bar is one of effective measures for forestation controlling and management of gravel-bed river.
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