The present study provides an analysis of floristic composition, vegetation types, and structure and species distribution at 20 sites, emphasising the environmental factors that affect species distribution. | Turkish Journal of Botany Turk J Bot (2013) 37: 894-907 © TÜBİTAK doi: Research Article Floristic diversity and vegetation analysis of Wadi Al-Noman, Mecca, Saudi Arabia 1,2, 3,4 1 Kadry ABDEL KHALIK *, Mohamed EL-SHEIKH , Abeer EL-AIDAROUS Biology Department, Faculty of Science, Umm-Al-Qura University, Mecca, Saudi Arabia 2 Botany Department, Faculty of Science, Sohag University, Sohag, Egypt 3 Botany and Microbiology Department, College of Science, King Saud University, Riyadh, Saudi Arabia 4 Botany Department, Faculty of Science, Damanhur University, Damanhur, Egypt 1 Received: Accepted: Published Online: Printed: Abstract: Wadi Al-Noman in Mecca is one of the most important wadis. It was included among the most important water sources where the springs and wells of Zobida run and it provides drinking water for the holy places in Mecca and visitors to the Kaaba and Arafat regions. The present study provides an analysis of floristic composition, vegetation types, and structure and species distribution at 20 sites, emphasising the environmental factors that affect species distribution. A total of 126 species representing 39 families of vascular plants are recorded. Fabaceae, Poaceae, and Boraginaceae are the largest families, and therophytes and chamaephytes are the most frequent, indicating a typical desert life-form spectrum. The floristic composition of the different geomorphologic landscape units shows differences in species richness. The highest species richness value (23 species stand–1) is recorded in the wadi bed. The lowest species richness value (18 species stand–1) is recorded in the wadi plateau and fissures. Chorological analysis revealed that 52% of the studied species are bioregional, native to the Saharo-Arabian–Sudano-Zambezian region. After application of the TWINSPAN, DCA, and CCA programs 4 vegetation groups were identified, and .
