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The present study, which was conducted between 2009 and 2010, provides an analysis of the floristic composition, life forms, phenology, chorological spectrum and analysis of the vegetation in the deltaic part of Wadi Qena using multivariate analysis techniques. Twenty-five stands were sampled to represent, as much as possible, the vegetation variation in the study area. A total of 54 species (nineteen annuals and 35 perennials) belonging to 47 genera and nineteen families were recorded. The largest families were Fabaceae and Brassicaceae (nine and seven, respectively), Asteraceae and Poaceae (six for each), Chenopodiaceae (five), and Zygophyllaceae (four). Therophytes are the predominant life form (37%) followed by chamaephytes (24%), phanerophytes (18.5%), hemicryptophytes (9.29%) and cryptophytes (5.5%). Chorological analysis revealed that Saharo-Arabian (48%) and the Sudano-Zambezian (19.2%) chorotypes constitute the main bulk (67.2%) of the total flora of the studied area. The majority of the perennial species behave similarly to each other in their phenology, and usually perennials sprout at the end of February, become leafy in March, flower in April and produce fruits between April and July. Three main vegetation groups resulted from classification of the dominant vegetation. Canonical correspondence analysis revealed that magnesium, potassium and pH were the most effective soil variables. Resume Realisee en 2009 et 2010, cette etude donne une analyse de la composition floristique, des formes de vie, de la phenologie, du spectre chorologique et une analyse de la vegetation dans la partie deltaique de l'Oued Qena en utilisant des techniques d'analyses multivariees. Des echantillons furent preleves en 25 endroits afin de representer autant que possible la variation de la vegetation dans la zone etudiee. Au total, on a releve la presence de 54 especes (19 annuelles et 35 perennes), appartenant a 47 genres et a 19 familles. Les plus grandes familles etaient les Fabaceae et les Brassicaceae (9 et 7 respectivement), les Asteraceae et les Poaceae (6 chacune), les Chenopodiaceae (5), les Zygophyllaceae (4). Les therophytes sont la forme vivante predominante (37%) suivis par les chamaephytes (24%), les phanerophytes (18.5%), les hemicryptophytes (9.29%) et les cryptophytes (5.5%). L'analyse chorologique a revele que les chorotypes saharo-arabe (48%) et soudano-zambezien (19.2%) constituent la plus grande partie (67.2%) du total de la flore dans la zone etudiee. La majorite des especes perennes se comportent de facon similaire dans leur phenologie : d'habitude, les perennes sortent a la fin de fevrier, font des feuilles en mars, fleurissent en avril et produisent des fruits entre avril et juillet. La classification da la vegetation dominante aboutit a trois groupes de vegetation principaux. Une analyse ACC a revele que le magnesium, le potassium et le pH sont les variables du sol les plus efficaces. |
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