Some Aspects of the Ecology of a Potentially Invasive Species in Martinique: The Case of Dichrostachys cinerea

Biological invasions are the second most significant cause of biodiversity loss. They lead to the introduction of exogenous plant species which today threaten autochthonous and/or endemic species. Indeed, many plant species have disappeared. Other highly endangered species are currently in danger of extinction. Human activities, the overexploitation of resources, climate change but also biological invasions have advanced these extinctions. These phenomena have led to the progressive deterioration of the environments and a decrease in the diversity of the landscapes (a considerable depletion of the plant ecosystem) thus contributing to a loss of biodiversity. Natural (cyclones, etc.) or anthropogenic (pollution, etc.) perturbations create openings in the ground cover allowing more competitive species to install themselves. Introduced plant species install themselves in the open areas caused by these perturbations. They overcome a succession of barriers (physical, geographic, environmental) before they can become invasive. When conditions are favourable to their installation, they develop there to the detriment of the native populations. Insular environments (islands) are more sensitive to the phenomena of biological invasions. In Martinique, forests have gradually degraded and are losing their ecosystem resilience. This favours the installation and development of invasive species. Dichrostachys cinerea is an introduced species which is native to Africa and which has become naturalised on the island of Martinique. It colonises extensively perturbed areas, fallow land, abandoned farm plots located in the south of the island. A floristic analysis of the forests of the communes of southern Martinique (Sainte Anne, Marin, Vauclin) was carried out in order to establish the ecological profile of this shrub.