Chapter 3. Geomorphology
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Many of the processes acting on arid-region river systems (e.g., channelized
flow, sheetfloods) may be associated with more than one of these five stream
types, but differences in the spatial and temporal distribution of processes give
rise to the distinctive stream types.
After a brief summary of basic principles in fluvial geomorphology, this
chapter will describe the processes associated with the five arid-region stream
types and the resulting morphological features that develop. The reasons that the
different stream types develop and the ways in which they differ from humid-
region perennial rivers are provided, followed by methods that may prove useful
in identifying the OHWM. The focus of this review is on alluvial channel forms
in arid regions (i.e., channels formed in river-deposited sediment) and does not
address bedrock channel forms in similar climates, recently described by Wohl
(1993) and Wohl et al. (1994).