Velocity distribution characteristics within the non-submerged sea buckthorn plant flexible dam

摘要

The seabuckthorn plant flexible dam (The SPFD) is a new type of ecological engineering, which can efficaciously control soil erosion and capture sediment in the Pisha sandstone gully within Loess Plateau of China. The seabuckthorn plant can resist flow due mainly to slowing velocity, and thus reduce the flow scour stress and the sediment carrying capacity. It is therefore necessary to analyze the flow velocity distribution within the SPFD. The results showed that: i) the SPFD has a significant effect on the both lengthwise and transverse directions; ii) the average transect velocity reduced progressively in longitudinal direction, and the width-averaged velocity in the same depth at each transect reduced along the lengthways direction; iii) the velocity distribution at transect shows the reverse-tongue pattern that is quite different from that of general river. This study can lay a significant foundation for further study on the vegetation resistance and its formulation as well as function.