<Table> <Tr> <Td> </Td> <Td> This article does not cite any sources . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (May 2018) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article does not cite any sources . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (May 2018) (Learn how and when to remove this template message) </Td> </Tr> <P> The depth--slope product is used to calculate the shear stress at the bed of an open channel containing fluid that is undergoing steady, uniform flow . It is widely used in river engineering, stream restoration, sedimentology, and fluvial geomorphology . It is the product of the water depth and the mean bed slope, along with the acceleration due to gravity and density of the fluid . </P> <P> The use of the depth--slope product--in computing the bed shear - stress--specifically refers to two assumptions that are widely applicable to natural river channels: that the angle of the channel from horizontal is small enough that it can be approximated as the slope by the small - angle formula, and that the channel is much wider than it is deep, and sidewall effects can be ignored . Although it is a simplistic approach to find the shear stress in what can often be a locally unsteady fluvial system, when averaged over distances of kilometers, these local variations average and the depth--slope product becomes a useful tool to understand shear stress in open channels such as rivers . </P>

What is the purpose of providing bed slope in open channel
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