Answer: River rejuvenation can have a significant impact on the grading of a river. When a river is rejuvenated, it means that the river has started to erode deeper into its bed, creating steeper banks and a steeper gradient. This can be caused by a variety of factors, such as tectonic uplift, changes in sea level, or changes in base level.
As the river erodes deeper, it will transport larger sediment sizes and create a steeper gradient. This can result in a change in the river's grading, or the distribution of sediment sizes along the river bed. With a steeper gradient, the river will be able to transport larger sediment sizes downstream, resulting in a coarser bed material.
In addition to changes in sediment size, river rejuvenation can also lead to changes in the river's channel pattern, such as the formation of meanders or the creation of a new channel. These changes can impact the river's hydraulic geometry, or the relationship between channel geometry and flow.
Overall, river rejuvenation can have a significant impact on the grading of a river, resulting in changes in sediment size, channel pattern, and hydraulic geometry. These changes can have both positive and negative impacts on the river ecosystem and nearby communities, depending on the specific circumstances.