Influence of stream channel characteristics on bed morphology and step-pool structure in a rhyolitic headstream watershed
Influence of stream channel characteristics on bed morphology and step-pool structure in a rhyolitic headstream watershed
复制标题
流纹岩源头流域河道特征对床层形态和阶梯池结构的影响
DOI：
10.1016/j.catena.2021.105427
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发表时间：
2021
期刊：
影响因子：
6.2
通讯作者：
Itsukushima Rei
中科院分区：
文献类型：
--
作者：
Itsukushima Rei;Kano Yuichi;Itsukushima Rei
河源区是研究河道自组织机制或河床形态发生特征的重要河段，因为它的沉积物来源和低人为影响（如淤地坝或河道改造）。然而，较少的工作已经进行了过渡的河床形态在非常高的梯度通道，不像在台阶池渠道。本文介绍了流纹质山地河源区河床形态特征的野外观测结果，以及阶池构造与河道特征的关系。与不同的床坡度的河床形态的过渡，通过现场观察确认。从上游到下游，主要的河床形态从瀑布到瀑布再到台阶。台阶的形成过程（水力控制型和楔型）与堵塞状态的关系也不同，堵塞状态的产生既有台阶组块的供给过程，也有台阶的外力作用。山区溪流受地质影响很大，这种趋势在源头地区可能更为明显。此外，影响河床形态或河道特征的因素包括山脉的形成年龄和气候，地质和断层带的缺乏。因此，需要了解各种地质和气象条件下源头地区的河床形态。
The headstream area is an important channel segment for investigating the self-organization mechanism of a stream channel or the occurrence characteristics of stream bed morphology owing to its sediment source and low anthropogenic impact such as that from check dams or channel modifications. However, less work has been conducted on the transition of stream bed morphology in channels with very high gradients, unlike in step–pool channels. This study describes the field observation results of the stream bed morphological characteristics and the relationship between the step–pool structure and stream channel characteristics in the headstream areas of rhyolitic mountains. The transition of the stream bed morphology associated with different bed slopes was confirmed through field observations. The dominant stream bed morphology changed from a fall to a cascade to a step, from upstream to downstream. Furthermore, the relationship was different between the step formation processes (hydraulic control and keystone types) and the jamming state, which was caused either by the supply process of the step constituent boulder or the external force of the step. Mountainous streams are strongly affected by geology, and this tendency is likely to be more pronounced in headstream areas. Further, the factors influencing stream bed morphology or stream channel characteristics include the formation age of mountains and the climate, geology, and the absence of fault zones. Therefore, knowledge of the stream bed morphology of headstream areas under various geological and meteorological conditions is required.