Influence of land use on the dynamics of plant communities in the Sahelian zone: case of the rural commune of Dantchandou (Niger).
The commune of Dantchandou is one of the main sources of wood supply in western Niger, causing a disorganization of the structure and composition of the landscape. The objective of this study is to evaluate the impact of cultivation, pasture, fallow land and the influence of the villages on the dynamics of the plant communities of the commune of Dantchandou. The data were collected in the different land use and land cover units (flat, slope, depression and foot of the plateaus). Plots of 50 m × 20 m were set in each sampling site taking into account the homogeneity of the vegetation in order to avoid edge effect. Thus, for the characterization of the vegetation, three transects were retained. A total of 76 surveys were conducted. Our results show an inventory of 151 plant species including 125 herbaceous species and 26 woody species distributed among 101 genera and 28 families. In fields and fallows 106 species were recorded which belong to 81 genera and 23 families. In the fallows the floristic composition is of 58 species from 47 genera and 17 families. On the plateaus 111 species belong to 24 families were recorded. The Shannon diversity index is higher in fallows with 5.16 bits followed by fields with 5.08 bits and finally on plateaus with 5.05 bits. This landscape diversity is linked to the different types of land use, shorter fallow periods, expansion of agrosystems, overgrazing resulting in the substitution of indigenous species by invasive species.