Bradshaw model

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The Bradshaw Model is a geographical model which describes how a river's characteristics vary between the upper course and lower course of a river. It shows that discharge, occupied channel width, channel depth and average load quantity increases downstream. Load particle size, channel bed roughness and gradient are all characteristics which decrease downstream.

The model first appears as an illustration in M J Bradshaw's 1978 high school textbook The Earth's Changing Surface. Bradshaw's illustration is a simplifcation of Stanley Schumm's river model which had been published a year earlier in The Fluvial System, although aspects of the model had already appeared in a series of academic papers over the previous 10 years. Schumm based his model on an empirical analysis of a variety of North American rivers and suggested that it could be used to predict how any given river channel would respond to changes in discharge or sediment supply caused by river engineering, such as a dam or flood relief channel.

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