Effet des Variables Agro-Écologiques sur la Distribution de la Végétation de la Rôneraie Anthropisée de Dasga au Niger

Abstract

The objective of this study is to contribute to the sustainable management of the Dasga palm trees forest by analyzing the phytodiversity and ecological parameters guiding the distribution of vegetation. The methods of phytosociological survey and multivariate analyzes were used. The vegetation surveys were carried out according to the sigmatistic approach of Braun-Blanquet (1932) and the multivariate analysis techniques used were those relating to factorial analysis of relaxed correspondence (DCA) and canonical correspondence analysis (CCA). A total of 144 species belonging to 100 genera and 50 families were recorded from 68 plots. This flora is dominated by a strong presence of therophytes and species with broad pantropical and palaeotropical distribution, thus showing an arid and perturbed environment. The multivariate analyzes (DCA and CCA) sow among the variables tested; only the slope and the crops were determinants in the structuring of the vegetation by the Monte Carlo permutation test. These ecological variables would appear to be the major parameters of species distribution. Thus the understanding of the relationships between vegetation and ecological parameters can be used as a tool for sustainable management of this palm trees forest.