This video presents the hydrological characterisation of the Limpopo and Shashe Rivers. The model integrates spatial analysis from Arc-GIS 10, remotely sensed data, mean statistical rainfall averages, and elevation dataset.

For the Shashe-Limpopo basin context, the yellow circle covers Samaria floodplain and the black circle covers Mapungubwe landscape.

As rainfall changes from 300 to 450 millimetres in the Shashe-Limpopo basin, the lowest lying sinks of the main channel fill up first. These are highlighted in green arrows.

As the water collects in nearby streams and low lying sinks down-stream,

The narrow gorge features (circled orange in-text) downstream of the Shashe-Limpopo confluence act as dam wall buffers, such that the intensity of flooding episodes are reduced (as shown in Figure fifty).

Noteworthy, a similar process was recorded by Fredrick Elton while crossing the middle Limpopo valley in the 1870s.

In a nutshell, the simulation shows that narrow passage/gorges act as a dam wall against the Shashe-Limpopo Rivers, forcing it to back up and inundate its tributaries. A clear indication of channel resilience.

The resulting model shows that heavy flooding occurs in low-lying valley plains due to the gradual overflow of the Shashe and Limpopo Rivers. In fact, supporting evidence for these hydrological processes is found in the soil micromorphological records of this are and, specifically, the presence of micro-laminar pedofeatures linked to overbank clastic sedimentation (as discussed in Chapter 5, section 5.7).

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