ARCHITECTURE RACINAIRE DE L’ARGANIER DE TOUIREF BOU AAM (TINDOUF, ALGERIE)

Abstract

In desert regions, development of root system and its orientation are not only closely linked to the physico-chemical composition, but also to the geomorphology of its substratum. The absorption of water represents a vital challenge for the botanical species. The argan tree is a strong example of adaptation in the conditions of aridity. Our study concerns the region of Tindouf (Algeria), where the argan tree remains in its most Southern and the most oriental area. It is with the aim of determining the root architecture of this species that the roots of twelve individuals, chosen at random to Touiref Bou Aam, were exposures. Biometric measures were made on the observed roots and samples of soil were taken for physico-chemical evaluations. The geomorphology was a support to understand the ecological situation and behavior of this species. The obtained results classified the individuals studied in two different groups separated according to the present correlations. A first group with numerous deep and little branched out roots evolving in a sands and unrefined silt predominant soil was observed on the realized PCA. This group is more centered on the anchoring of the tree. On the other hand, the second group contains samples with thick, very branched out superficial roots and some deep roots with a predominant sands and fine silt soil with an important retention capacity. A first representation of the space root distribution was performed. It allows to understand the root behavior of the argan tree in front of the extreme aridity of its environment.