The role of vegetation in the formation of linear sand dunes

Abstract

A recent change in the vegetation cover of linear dunes in the Negev desert forms the basis for the study of the effect of vegetation on linear dune morphology. Linear dunes are elongated with little erosion of sand. The upshot is more protection of sand moisture which in turn sustains the relatively dense plant cover on this particular dune type in deserts. Destruction of the vegetation brings about abrupt change in the morphology of linear dunes and turns them into linear braided and seif dunes. This process was analyzed by aerial photographs and computer-aided photogrammetric mapping. Vegetated linear dunes align parallel to dominant wind direction while seif dunes stretch between two main dominant wind directions blowing on both sides of them at an angle of 30° ± 10° with the dune crestline.