Abstract
A study was conducted during 2006 and 2007 in Eastern Saudi Arabia to provide the needed information about the vegetation of sand dunes and sabkhas in the region and to provide insight into the factors controlling community distribution. Eastern Saudi Arabia with arid climatic conditions has sparsely distributed sand dune and sabkha vegetation cover. The vegetation comprises of perennial herbs, dwarf shrubs and few tree species. Seven major plant communities were recognized according to their dominant and co-dominant species: Panicum turgidum-Stipa capensis, Panicum turgidum-Pennisetum divisum, Panicum turgidum-Zygophyllum coccineum, Lasiurus scindicus-Stipagrostis plumose, Aeluropus lagopoides-Halopeplis perfoliata, Tamafix arabica-Aeluropus lagopoides and Zygophyllum coccineum-Cyperus conglomeratus. The seven communities represented different combinations of species. Soil organic carbon, soil salinity and soil water holding capacity appear to have a substantial influence on determining vegetation composition and abundance. In general, there are 45 species in the study area differing in their relative abundance, frequency and richness.
