Floristic Diversity of Jeddah: An Arid Desert, Western Region of Saudi Arabia

THIS STUDY was conducted in the arid deserts of Jeddah Governorate in the western region of Saudi Arabia. The main objective is to determine the floristic composition of the area, including an explanation of its different life forms and the chorology of the recorded species. A total of 107 taxa belonging to 77 genera in 31 families of the Angiospermae were recorded. Fabaceae and Poaceae account for approximately 31.8% of the recorded species in the study area. The data also reflect a high degree of monotypic, where 42% of the recorded families were represented by a single species, and 76.6% of the genera were monotypic. Perennial species dominated the plant cover with 62%, defining the character of the vegetation, while annuals were represented by about 38%. The most common lifeforms were therophytes and chamaephytes. Chronological analysis of the floristic data revealed that the biregionalSaharo-Arabian-Sudanianchorotypeis the most dominant in the Jeddah area (18.7%), followed by the two monoregionalSudanian and Saharo-Arabian chorotypes (12.1 and 11.2%, respectively). The results also showed the predominance of biregional taxa (38.32%) over the other phytogeographical elements followed by the monoregionaltaxa (28.97%). The IUCN Red List includes 17 of the species recorded in this study in the least concern category. The current study's findings could be useful for the conservation and management of the study area.