Fluvial instabilities originate from an interplay between the carrier fluid and the erodible loose boundary at their interface, manifesting a variety of sedimentary architectures with length scales spanning from a few millimeters to hundreds of meters. This review sheds light on the current state-of-the-science of the subject, explaining the fluvial instabilities from three broad perspectives. They are micro-scale, meso-scale, and macro-scale instabilities. The interactions between the near-bed hydrodynamics and the sediment dynamics in generating various kinds of instabilities, including their natures and driving mechanisms, are thoroughly appraised in the light of laboratory experimental results, field observations, and theoretical backgrounds. Besides, this review addresses the current challenges, delineating key points as a future research scope.

中文翻译：

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河流不稳定

河流不稳定性起因于载流体和易蚀的松散边界在界面处的相互作用，从而表现出各种沉积构造，其长度范围从几毫米到几百米。这篇综述阐明了该主题的当前科学状态，从三个广泛的角度解释了河流的不稳定性。它们是微观，中尺度和宏观尺度的不稳定性。根据实验室的实验结果，现场观察和理论背景，对近地层水动力和沉积物动力在产生各种不稳定性，包括其性质和驱动机理方面的相互作用进行了全面的评价。此外，这项审查解决了当前的挑战，