Abstract :

Eichhornia crassipes (water hyacinth) is one of the world’s most invasive aquatic plants, causing severe ecological and socio-economic impacts in freshwater ecosystems, including those of Côte d’Ivoire. This study aimed to assess the current and future distribution of E. crassipes in the wetlands of Côte d’Ivoire. Species occurrence data were compiled, and future distribution projections were generated under two Shared Socioeconomic Pathways (SSPs): SSP2-4.5 (intermediate stabilization scenario) and SSP5-8.5 (high greenhouse gas emission scenario) for the 2050 and 2070 time horizons. The results indicate that climate change is expected to substantially promote the expansion of E. crassipes across Côte d’Ivoire. Rising minimum temperatures (Bio6), identified as the primary determinant of the species’ distribution, together with changes in precipitation patterns, are projected to create highly suitable environmental conditions over most of the country by 2070. Depending on the climate scenario, the species’ potential suitable habitat could increase by a factor of 11 to 21, with no projected loss of currently suitable habitats. These findings highlight the urgent need to implement proactive prevention, monitoring, and management strategies, particularly in the central and northern regions of the country, which are currently free from invasion.

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Keywords :

climate change, Côte d’Ivoire, Eichhornia Crassipes, species distribution, wetlands

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