The effects of the 2000 floods on channel type heterogeneity in the Sabie River, Kruger National Park, South Africa

The naturally dynamic flow regime of a river promotes heterogeneity in channel types
found within the river and therefore also promotes diversity in the riverine flora and
fauna. Increased sedimentation in the Sabie River caused by logging and farming in the
catchment area seemed to be shifting all channel types towards an alluvial-dominated
state, causing a loss in species dependent upon bedrock-dominated areas. However, the
2000 floods on the Sabie River drastically changed the template of the river, removing a
great deal of vegetation and redistributing sediment. Examining an aerial photo history of
sites along the Sabie River reveals that the flood returned the river system to a state
similar to the river’s condition after the last large flood in 1921, suggesting that the 1:100
year floods periodically reset the river system in an episodic model of change.