[1] Recent research has demonstrated that image processing can be
applied to derive surficial median grain size data automatically from
high-resolution airborne digital imagery in fluvial environments.
However, at the present time, automated grain size measurement is
limited to the dry exposed bed areas of the channel. This paper shows
that the application area of automated grain size mapping can be
extended in order to include the shallow wetted areas of the channel.
The paper then proceeds to illustrate how automated grain size
measurement in both dry and shallow wetted areas can be used to measure
grain sizes automatically for long river lengths. For the present
study, this results in a median grain size profile covering an 80 km
long river which is constructed from over three million automated grain
size measurements.