Plant - Water - Sediment Interactions Studies

In the engineering field, the relationship between vegetation, water and sediment, has been researched by domestic and foreign experts and scholars. Vegetation in water, on the one hand vegetation increases the resistance of the river, slows the flow rate of rivers, results in rising water level of rivers, reduces the flood discharge capacity of the river; on the other hand, vegetation in water reduces the capacity of river sediment transport, promotes sediment deposition to prevent beach flood erosion. The existence of the plant leads to the flow turbulence diffusion coefficient decreasing, not only can effectively block bedload sediment's movement, can also effectively intercept suspended sediment, promote sediment deposition, directly affect the suspended sediment concentration in the distribution of the vertical. However, up to date, the problem of the interaction between the plants-sediment-water is still in the research stage. Therefore, it is necessary to conduct further studies of sediment-laden flow with vegetation.This paper systematically summarizes the findings of previous vegetation sediment-laden flow, and vegetation sediment-laden flow based on the presence of sediment form is divided into two categories:(1) plant-water-suspended sediment mud sand flow structure;(2) plant-water-bed load sediment in the flow structure. This article is with respect to their experimental study, and the main contents are as follows:(1) the study of plant-water-suspended sediment in river flow structure includes instantaneous flow field and typical sections of suspended sediment concentration with three-dimensional ultrasound Doppler Velocimeter (ADV) measurements at different positiens with the height of the different plants and under different flow, the analysis of longitudinal surface line of the water, the average velocity on cross-section, the typical cross-section of vertical mean velocity, the equivalent roughness whether with plant nor sediment.(2) the study of plants-water-bed load sediment in the flow structure includes instantaneous flow field and typical sections of suspended sediment concentration with ADV measurements at different posiuons with the height of the different plants and under different flow, the analysis of longitudinal surface line of the water, the average velocity on cross-section, the typical cross-section of vertical mean velocity and the equivalent roughness whether with plant nor sediment.