Aeolian and fluvial systems are usually studied independently which leaves many questions unresolved in terms of how they interact. When sand dunes and rivers coincide with each other, the interaction of sediment transport fluxes between the two systems may lead to change in either or both systems therefore can significantly change surface morphology. The ephemeral Huab River in Namibia marks the start border of the Skeleton Erg, at where sand dune fields have been evolved in adjacent to the channel and northward, until they meet the Kuenne River. To find out what impact the fluvial regime has on adjacent dune field development, celluar CAESAR-LISFLOOD model has been coupled with a dune model to simulate the fluvial and aeolian landscape, in combination with field observations.