Etude d'adaptation des Géophytes des parcours du Sahara septentrional algérien (cas de la commune de Metlili)

Abstract

The study is to reach an idea on the adaptation of spontaneous plants we mention the geophytes of northern Algerian Sahara Case of the municipality Metlili accomplish in four a stations: Oued El Drine, Chaab Ismail, Oued Mask, Oued Lahssen besder. To facilitate quantitative studies, in each station we identified substations of different geomorphological formations of 100m² in which we applied the different floristic records. From which were determined: The result of the floristic inventory show that the number of species inventoried is 25species belonging to 16 Family and the most representative: Apiaceae, among these species 19 are perennial and 6 are Ephemeral we note that the most abundant species is Asphodelus tenuifolius 46%, the average covering of the Geophytes we notice that the second highest station 0.636m². In the light of this study we have made concerns the plants studied (type Geophyte) different adaptation mechanism they are summarized in: Morphological adaptation; reduction of the leaf surface in the form of needles such, Phenological adaptation; the plant spends the dry season as a bulb or a rhizome and Physiological adaptation. We also touched on a histological study of some plants, and we were acquainted with the various tissues that change at their level to ensure the adaptation of the plant in times of drought and difficult conditions.