Habitat biophysical and spatial patterns assessment within Oti-Keran-Mandouri protected area network in Togo

Abstract

Oti-Keran-Mandouri (OKM) is part of the elephant historical range and one of the priority corridors proposed for elephant conservation in West Africa. However, its potentialities to be a functional corridor are yet to be evaluated in a context of increasing anthropogenic pressure. This study aims at assessing habitat biophysical patterns and fragmentation level. A multicriteria evaluation using fuzzy logic was performed to model elephant habitat suitability and vegetation sampling conducted in 123 plots to describe the habitat. In each plot, the physical parameters of woody plants species were recorded. Biodiversity indices, dendrometric parameters, and diameter structure were computed for each habitat type and compared using Jaccard Index and Kruskal-Wallis test. Habitat fragmentation was assessed using the hypsometric method. Apart from a core area located in the south-east, the remnant good habitat is in small patches. Four habitats were distinguished based on their level of degradation. There is a steady increase in habitat diversity from degraded habitat (Habitat 1) to primary habitat (Habitat 4) with the Shannon index increasing from 0.83 to 1.43 bit. In all the habitats, trees are evenly distributed with an evenness higher than 0.7. Dendrometric parameters are significantly different from one habitat to another (P-value < 0.05) apart from the mean diameter and the average regeneration rate. The suitable habitat for elephant constitutes only 31.5% of the area of OKM. The overall habitat fragmentation is 84.74%. Regeneration rates make an eventual restoration possible but further assessment of the socio-ecological system is needed.