The role of morphology on the displacement of particles in a step–pool river system
The role of morphology on the displacement of particles in a step–pool river system
复制标题
阶梯池河流系统中形态对颗粒位移的作用
DOI：
10.1016/j.geomorph.2007.11.005
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发表时间：
2008
期刊：
影响因子：
3.9
通讯作者：
A. Roy
中科院分区：
文献类型：
--
作者：
H. Lamarre;A. Roy
尽管近年来关于陡峭和粗粒河道中泥沙运动的研究越来越多，但对阶梯塘河流系统中泥沙运动的动力学仍然知之甚少。本文研究了单个碎屑流经典型的阶梯塘水道--云杉溪流的位移，以及河道形态对碎屑路径长度的影响。无源集成应答器标签(PIT)被用来跟踪196个单个颗粒物在包括堤岸满阶段在内的一系列放电过程中的位移。在五次洪水事件之后，对碎屑进行了追踪。结果表明，距离分布符合双参数Gamma模型。在每个洪水事件序列中，所研究的颗粒大小发生了相同的迁移率传输。碎屑的平均行进距离可以从过剩的水流功率中估计出来，碎屑的迁移率比在冲洗池河道中报道的模型小一个数量级以上。地层的主要形态长度标度也控制着碎屑的路径长度。这些结果证实了有关阶梯塘河道泥沙输移的一些初步观测结果。
Although studies of sediment transport in steep and coarse-grained channels have been more numerous in recent years, the dynamics of sediment transport in step–pool river systems remain poorly understood. This paper investigates displacements of individual clasts through Spruce Creek (Québec, Canada), a classic step–pool channel, and the effects of the channel morphology on the path length of the clasts. Passive integrated transponder tags (PIT) were used to track the displacement of 196 individual particles over a range of discharges including the bankfull stage. Clasts were tracked after five sequences of flood events. The results showed that the distance distributions match a two-parameter Gamma model. Equal mobility transport occurs for the particle size investigated during each sequence of flood events. Mean travel distance of the clasts can be estimated from excess stream power, and the mobility of the clasts is more than an order of magnitude less than the model reported in riffle–pool channels. The dominant morphological length scale of the bed also controls the path length of the clasts. These results confirm some preliminary observations on sediment transport in step–pool channels.