Effect of trees’ basal area and substrate on the regeneration in the Rubi Tele Domaine de Chasse mature forest

Abstract

The aim of the present study is to analyze the effect of trees’ basal area and substrate on the regeneration in the Rubi Tele Domaine de Chasse (RTDC) mature forests. The RTDC straddles the Tshopo and the Bas-Uélé provinces in the North-Eastern part of the Democratic Republic of the Congo (DRC). A census of all shrubs and arborescent individuals with 1 cm diameter at least was realized in twenty (20) plots of 0.05 ha (100 m X 5 m) each. Simultaneous accumulation of area showed in the understory layer the appearance of 95 species (2195 individuals) in the mature forest established on Periodically Flooded soils (PI) and 82 species (3192 individuals) in the mature forest established on dry gravelly soil (Gr). The mean rate of the arborescent basal recovery to the inventory area of each plot (0.05 ha) was 2.16% (Gr) and 1.54% (PI). The arborescent and understory layers showed a common floristic procession (Index of Jaccard) of 36.36% in mature forests established on Gr and 25.61% in mature forests established on PI. The effect of trees’ basal area and substrate (explained variance: 69.26%, RDA1: 85.46%, RDA2: 4.56%) on the understory layer’s spatial organization was also observed.