标题：LA DIVERSITÉ VÉGÉTALE DANS UN MILIEU DE TRANSITION ENTRE LES ÉTAGES BIOCLIMATIQUES MÉDITERRANÉENS ARIDE ET SAHARIEN. CAS DU SECTEUR D’OULED DABBEB, TUNISIE
摘要：Vegetable diversity of a transitional environment between the arid and the Sahara bioclimatic stages. Case-study Ouled Dabbeb, Tunisia. The apparent monotony of the sparse steppe vegetation in the area of Ouled Dabbeb in southern Tunisia conceals a wide variety of flora and physiognomy. Based on several fieldcampaigns observations, the statistical analysis of collected data and a detailed phytoecological mapping, this work aims to highlight the influence of microtopography and topoclimates on the distribution of plant communities and on their diversity in the study-area. Indeed, most of the slopes of the pediments strips exposed to the South and South-East are marked by the presence of arid species e.g. Anthyllis sericea, Calligonum comosum, while the slopes facing North and North-East are marked by the presence of dry species e.g. Hammada scoparia, Hammada schmittiana. Therefore, a set of adjustments between climate and soil conditions at local level is at the origin of this fine mosaic of vegetal cover in the Ouled Dabbeb steppe region, where various plant species are coming into contact.
