River channels on the Okavango Fan evolve from a system of connected flooded pools (malapos) in which rooted swamp vegetation grows and confines water flow causing incision. The resulting channel encourages further plant growth and the take over of a pioneer flora by a papyrus-dominated flora. Peat levees develop which further confine flow, allowing aggragation of the channel and its sediment fill to the point where waterloss becomes acute and avulsion become probable. Bedload meandering and low sinuosity fluvial channel systems are possible where vegetation is sufficient to produce confining peat levees.