摘要：Physical modelling experiments are conducted to investigate if a
modification of the Isère River (French Alps) hydrology by changing dams
management is able to foster riverbed morphodynamic and, thus limiting
riparian plant development. The experimental setup is a 1:35 scale,
undistorted movable bed designed to ensure the Froude number similarity
and initial conditions for sediment particle motion. The physical model is 35
m long, 2.6 m wide, with a sand mixture composed of three grain size
classes. Two runs with different flow and bed load conditions are simulated.
Preliminary results show an intense riverbed activity when the system
reaches a dynamic equilibrium state. Under these conditions, bar mobility is
strong enough to limit vegetation encroachment only when water discharges
are higher than the discharge of a 5-years flood during more than 10 days.
These results indicate that the hydrological characteristics of the Isère River
and the actual configuration of the hydropower structures could be not able
to release annually the flow conditions needed to control riparian plant
development.
其他摘要：Physical modelling experiments are conducted to investigate if a modification of the Isère River (French Alps) hydrology by changing dams management is able to foster riverbed morphodynamic and, thus limiting riparian plant development. The experimental setup is a 1:35 scale, undistorted movable bed designed to ensure the Froude number similarity and initial conditions for sediment particle motion. The physical model is 35 m long, 2.6 m wide, with a sand mixture composed of three grain size classes. Two runs with different flow and bed load conditions are simulated. Preliminary results show an intense riverbed activity when the system reaches a dynamic equilibrium state. Under these conditions, bar mobility is strong enough to limit vegetation encroachment only when water discharges are higher than the discharge of a 5-years flood during more than 10 days. These results indicate that the hydrological characteristics of the Isère River and the actual configuration of the hydropower structures could be not able to release annually the flow conditions needed to control riparian plant development.
