An appraisal of eremophyte diversity and plant traits in a rocky desert of the Sahara

Abstract

This study aims to identify and describe community characteristics and species traits of eremophytic vegetation in the Hammada of Debdeb (Illizi, Algerian Sahara). We recorded abundance, species richness, biodiversity (Shannon index and evenness) and plant traits (life forms, dispersal types, morphological types, adaptive strategies of Grime, Noy-Meir’s categories and phytogeographical types). The results revealed the presence of 14 plant species in 11 families with the dominance of Asteraceae. The dominant plant taxa at surveyed sites of the Hammada desert were chamaephytes, perennials and anemochorous plants whereas the dominant phytogeographical origin of plants is the Saharo-Arabian type. According to Grime’s classification, most of plant strategies were stress-tolerant, followed by the stress-tolerant ruderal type. In addition, arido-active species predominated over arido-passive plants. The eremophytic vegetation of the Hammada is characterized by low species density (Shannon index ranged between 1.12 and 2.84, evenness from 0.48 to 0.82). The xerophytic species of the rocky desert under study have sparse and scattered spatial distribution with low density. Plant traits of this eremophilous flora denote its strategies to adapt to adverse environmental conditions of the Hammada desert including the hot hyper-arid climate and the extremely poor rocky-substrate.