Climate change impact projection on spatial distribution of Zanthoxylum zanthoxyloides (lam.) z & t. – a threatened medicinal plant in Benin (West Africa)

Abstract

Climate change constitutes nowadays another kind of threat for useful plant species in West Africa. This study aims to identify the suitable areas for  conservation of Zanthoxylum zanthoxyloides under the current and the future climate. The occurrences of Z. zanthoxyloides were associated with  current and four future scenarios data. Two Species Distribution modeling methods (MaxEnt and MaxLike) were used in R software packages and  the results were compared for identifying the most acceptable method. MaxLike method results were more valid than Maxent’s giving the latter’s  uncertainty. With MaxLike’s method, about 52% of Beninese territory was detected to be suitable for Z. zanthoxyloides production in the current  climatic conditions. These areas were localized in southern and central Benin with a good coverage by the included protected areas. The predicted  distributions of Z. zanthoxyloides in Benin under the four different emissions scenarios have shown a no significant impact of climate change on its  current suitable areas. The challenge for conservation of Z. zanthoxyloides in climate change conditions is needless. It is suggested further  investigations in impacts of land uses and medicinal uses on survival of Z. zanthoxyloides for better positioning of the suitable conservation   strategies in present situation of limited resources for conservation.