Impact of the chemical properties of different soil units on the dynamics of vegetal biodiversity in the Benoue National Park and its Western and Northern peripheries

Abstract

This work aims at determining the impact of soils' chemical properties on the dynamics of biodiversity in the Benoue National Park (BNP) of Cameroon and its peripheries (surrounding hunting concessions N ° 1, 4, 5 and 7). Nine, out of the sixteen soil units encountered in the BNP were studied, because of their accessibility. On each of these nine soil units studied, three elementary plots were materialized for the collection of soil samples and for the study of vegetation dynamics. The chemical parameters were evaluated according to appropriate methods and the dynamics of the vegetation was obtained by carrying out a floristic inventory. Heterogeneity was observed in the chemical parameters of the different soil units. Soil units S5 and S6 are the most damaged regarding their low organic matter content (0.95 ± 0.78%) and (1.02 ± 0.33%), their carbon (5.53 ± 4.54 g.kg-1) and (5.91 ± 1.93 g.kg-1) and nitrogen (1.20 ± 0.45 g.kg-1) and (1.89 ± 0.41 g.kg-1) contents and a very low C/N ratio (4.72 ± 3.96) and (3.29 ± 1.37) respectively. These soils also have a low floristic abundance S5 (22 ± 0.53 individuals) and S6 (8 ± 1.86 individuals) unlike S4 which has good chemical properties, according to its OM (5.60 ± 0.83 %) and carbon (32.49 ± 4.79 g.kg-1) content, and C/N ratio (22.38 ± 6.84). Consequently, its floristic abundance (75 ± 1.37 individuals) and diversity (18.42 %) are considerable. These results show that the degree of chemical degradation varies according to soils. Elsewhere chemical properties of the soil influence the dynamics and sustainability of the biodiversity.