The potential for mapping in‐channel morphology within shallow gravel‐bed rivers using airborne multispectral imagery and aerial photography is illustrated using a case study from the River Tummel, Scotland. The technique described relies on a good correlation between observed light reflectance levels from a water body and water depth. Measured water depths are regressed against reflectance levels derived from airborne multispectral imagery and black‐and‐white aerial photographs, to obtain equations that can be used for mapping channel bathymetry. The technique has a great deal of potential for wide‐ranging applications, including detailed morphological surveys, assessing in‐channel changes and mapping riverine habitats.© 1997 John Wiley & Sons, Ltd.

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Air photo interpretation and field survey were used to examine rates and patterns of planform change over the last 40 years on an 80 km reach of the Luangwa River, Zambia. The river, a tributary of the Zambezi, is a 100±200 m wide, medium sinuosity sand-bed river (sinuosity index 1Á84). High rates of channel migration (`33 m a À1 ) and cutoffs on meandering sections are frequent. Some meandering reaches, however, have remained relatively stable. A form of anastomosing with anabranches up to 14 km in length is also a characteristic. Patterns of meander development vary between bends but all can be described in relation to traditional geomorphic models; change occurs by translation, rotation, double-heading, concave bank bench formation and cutoff causing river realignment. At the local scale spatial variability in bank resistance, induced by floodplain sedimentology, controls rate of bank erosion, and valley-side channel`deflection' is also apparent.

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