Riparian Vegetation and Braided Stream Dynamics

Goal:

1. To study and quantify the interactions between riparian vegetation, channel morphology, and flow dynamics.

2. To investigate how river systems self-organize as a result of these interactions.

3. To investigate spatial and dynamic scaling in braided rivers with and without vegetation.

Reseachers: Michal Tal, Chris Paola, Elizabeth Tilman (Water Resources, Univ. of MN), Efi Foufoula-Georgiou (Civil Engineering, Univ. of MN)

Result:

Ongoing experiments at the St. Anthony Falls Laboratory are designed to isolate the effects of vegetation on braided stream dynamics. These experiments show how a fully braided stream with a noncohesive bed transitions to a single-thread (meandering) system when continuously forced with vegetation. Time-lapse photography and measurements of bed topography, flow depth, sediment output, and flow velocities enable us to study and quantify the morphodynamics of the system associated with this change.

研究目标：
1. 研究并量化河岸植被（riparian vegetation）、河道地貌（channel morphology）与水流动力（flow dynamics）之间的相互作用。
2. 探究此类相互作用下河流系统的自组织机制。
3. 探究有、无植被情况下辫状河流（braided rivers）的空间与动态尺度特征。

研究人员：Michal Tal、Chris Paola、Elizabeth Tilman（水资源系，明尼苏达大学（Univ. of MN））、Efi Foufoula-Georgiou（土木工程系，明尼苏达大学（Univ. of MN））

研究成果：
圣安东尼瀑布实验室（St. Anthony Falls Laboratory）目前正在开展的实验旨在分离植被对辫状河道动力过程的影响。实验结果表明，当持续受植被作用时，由非黏性床沙组成的完整辫状河道系统会转变为单一河道（蜿蜒型）系统。通过延时摄影、床面地形（bed topography）测量、水流深度监测、泥沙输出量（sediment output）测定以及水流流速测量，我们得以研究并量化该系统在此转变过程中的地貌动力学（morphodynamics）特征。