For two successive years, the floristic diversity and vegetation composition in the southern part of the Eastern Desert of Egypt were investigated through four transects (3 crossing the Eastern Desert and one along the Red Sea). The data collected from 142 stands covering the study area included the species composition, functional groups, chorologyand occurrences (Qvalues). A total of 94 plant species belonging to 33 different families were recorded, with Asteracea,  Zygophyllaceae,  Fabaceae, Poaceae,  Chenopodiaceae and  Brassicaceae as  the  largest  families.  Shrubs  represented  the  largest functional  group  (39.4%),while perennial herbs represented the smallest ones(12.8%). Species occurrence (Q-value) revealed that  Zilla spinosa,  Acacia tortilis  subsp. raddiana,  Morettia philaeana, Caroxylon imbricatum, Zygophyllum coccineumandCitrullus colocynthis had wide ecological range of distribution (dominant species,Q-values ≥0.2). Saharo-Arabian chorotype was highly represented (72.6 %) in  the  flora  of  this  area,  eventually  as  mono,  bi  or  pluriregional.  Classification  of  the  data  set  yielded  7  vegetation  groups included: (A)  Zilla spinosa-Morettia philaeana, (B1)  Zilla spinosa-Citrullus colocynthis-Morettia philaeana,(B2)Zilla spinosa,
(C1)  Zygophyllum  album-Tamarix  nilotica, (C2)  Zygophyllum  coccineum-Tamarix  nilotica,  (D1)  Zilla  spinosa-Zygophyllum coccineum and  (D2)  Zilla  spinosa-Acacia  tortilis  subsp.  raddiana-Tamarix  aphylla-Balanites  aegyptiaca. Certain  vegetation groups  were  assigned  to  one  or  more  transects.  Detrended  Correspondence  Analysis  (DCA)  revealed  that  electrical conductivity, sodium, potassium, calcium, magnesium, chlorides, moisture content, sulphates, pH, organic matter and gravel were the soil variables that affect the species distribution in this study.
Research Abstract	
              Research Department	
              
          Research Journal	
              Notulae Scientia Biologicae
          Research Member	
          
      Research Publisher	
              Acadimic pres
          Research Rank	
              1
          Research Vol	
              6 (1)
          Research Website	
              www.notulaebiologicae.ro
          Research Year	
              2014
          Research Pages	
              41-58