Facteurs déterminant l’abondance de Sericostachys scandens (Amaranthaceae) dans le Parc National de la Kibira au Burundi.
J. Anim. Plant. Sci
Habonayo, R., Azihou, A. F., Dassou, G. H., Adomou, A. C., & Habonimana, B.
J. Anim. Plant. Sci
The biological invasion is a major threat on the conservation of the biodiversity. The main objective of the study is to analyse the factors that influence the abundance of the invasive liana Sericostachys scandens Gilg & Lopr. (Amaranthaceae) in Kibira National Park, Burundi. The sampling of this liana was carried out at the scale of the park considering the invasion level and intensity on the one hand and the altitude on the other hand. The data were collected within plots of 50 m × 50 m each, evenly distributed over the invaded areas and the non-invaded ones. Within each plot, individuals with dbh ≥ 1 cm were targeted, counted, and their diameter at breast height (dbh) measured at 1.30 m above the ground. A total of 100 plots were surveyed. The comparison of the factors according to the invasion or not and the exposition has been carried out using the test of Wilcoxon, the analysis of variance and the exact test of Fisher. Their effect on the abundance of the liana was evaluated by a multiple regression on number of individual of S. scandens. The results identified the distance to the forest edge, the canopy cover and the altitude as variables influencing significantly the abundance of S. scandens (p = 0,025, p < 0.0001 and p = 0.022 respectively), the canopy cover remaining the major factor whose influence is enormous. The density of S. scandens decreased with the increase of the distance from forest edge to the forest interior or with the increase of the altitude. Its density decreased also with increasing of the canopy cover. It turns out from this study that the human disturbances were the causing factor of the expansion of this invading liana. The managers of Kibira National Park should strengthen patrols to prevent or reduce human disturbance actions.