Dynamique de Colonisation des Zones Rudérales d’un Massif Forestier Urbain par les Espèces Végétales Exotiques Envahissantes : Cas du Parc National du Banco (Côte d’Ivoire)

Abstract

The ruderal areas are starting points for invasion of natural ecosystems by invasive exotic plant. In this study we have inventoried all the invasive plants present in the PNB, highlighted their spatial distribution and followed their evolution of occupation of the soil. The floristic data were first collected by itinerant inventory in the study area. At the end of this inventory, six zones of strong presence of invasive plants were selected: under of high voltage lines, the roadside, the arboretum, the encampments (destroyed encampment and current encampment), the periphery of the park and the portion of Anguédédou forest attached to park, which represents the not ruderal zone occupied by invasive species. Thereafter that of phytosociological records carried inside 203 permanent plots of 50 m². Inside each plot, all invasive species were inventory, counted, and their area of soil occupation was measured consecutive, from 2016 to 2018. 22 species counted, one of which proven invasive and 21 potentially invasive distributed throughout the park. Chromolaena odorata and Hopea odorara constitute a real threat to this park. The encampments, the periphery of the park are the most invaded places in the park. The spatio-temporal dynamics of the species species occupy 12,01 ha of the ruderal areas of the park and 126,84 ha taking into account the planted area of Hopea odorata is 3,68 % of the total surface of the park. These results will make it possible to anticipate and of coordinate actions in order to avoid the large-scale invasion of the park