Analysis of phytological and phytoecological aspects of groups of Malva subovata (DC.) Molero & J.M. Monts. in Mounts of Traras was studied. The interpretation was done by correspondence analysis (AFC), the latter makes it possible to seek the affinities which exist between the species or the statements, it aiming to study the dynamics of vegetation and the nature of their evolution in the study environment. This approach allowed to identify groups based on the studied species and specially to know these phytosociological groupings, it presents a broad ecological spectrum. This global treatment allowed one to have an overview of plant formations and to verify that there is indeed an original floral procession. Using phytosociological and phytodynamic data, it was possible to understand the evolution of this species as well as its diversity. In this research, a phytoecological analysis is evident. More than 40 families have been listed. Results showed the importance of the phyto-diversity of the region studied. Bangladesh J. Bot. 51(4): 821-827, 2022 (December)

This study is based on a ruderal species: Malva subovata = Lavatera maritima which should normally grow in the littoral, under maritime influence. Its presence in the matorrals is highlighted for the first time. as it has been found far from its natural habitat. The comparison of the different biological and morphological spectra shows the importance of the therophytes that confirms the phenomenon of degradation. This degradation shows a depletion of the floristic procession, especially concerning sylvatic species which have given way to ephemeral therophytes and chamæphytes. Despite the presence of a shrubby layer, it is no longer a question of a forest ecosystem but of a pre-forest ecosystem. To better understand the characteristics of this Malvaceae in terms of resistance and adaptation in matorrals, we often use the phytomass of all anthropozoic formations and more specifically the phytomass of the species that characterize this group. In our case, this is Malva subovata. The results of the morphometric study constitute a basic element for the evaluation of the adaptive potential of our Lavatère against the degradation factors.

The argan (Argania spinosa) is a xerothermophilous tree, endemic in North-West Africa. In Algeria, it is found as wild in the northwest of the Hamada du Drâa of Tindouf (Algerian Western Sahara), where it is characterized by a great floristic diversity. Several indices were calculated in this study to have a better knowledge on the state of biological diversity of the argan tree ecosystem. It is characterized by a floristic richness composed of 123 taxa belonging to 38 families including the dominance of three major floristic families: Asteraceae, Brassicaceae and Amaranthaceae. Biologically, the study area is dominated by therophytic species. This therophytization is marked by a general invasion of annual species. The diversity index of Shannon-Weaver (4.42) associated with that of Pilou's equitability (0.843) are relatively high, which showed that the flora of the argan forest of Tindouf is highly diverse. The disturbance index is high (76%) which reflects a significant degree of disturbance of the plant formation and also a strong anthropozoic influence. Bangladesh J. Bot. 53(3): 447-457, 2024 (September)