Assessing tree diversity in cashew plantations: Environmental and agronomic determinants in buffer zones of Mont Sangbé National Park, western Côte d’Ivoire

Within the framework of the rapid expansion of cashew plantations in West Africa, this research aims to investigate the floristic diversity of tree species associated with plantations positioned on the periphery of Mont Sangbé National Park in Côte d’Ivoire. The principal objective of this study is to assess the factors influencing this diversity, particularly cultivated areas, plantation age, and proximity to the MSNP. Surveys were conducted in three villages proximate to MSNP (Toulo, Gbeteman, Sorotonan), where 180 households were interviewed. Land and floristic data were collected via digital questionnaires, which were supplemented by field visits. A total of 272 plantations were documented, and 31 tree species were identified. Diversity indices-including species richness, Shannon, Simpson, and Pielou’s evenness-were calculated using the Vegan package in R. Non-parametric tests (Kruskal–Wallis and Dunn’s post hoc) facilitated the comparisons at the village level, while linear mixed models evaluated the effects of explanatory variables. Significant disparities were observed across the villages: Toulo exhibited the largest plantations and the highest floristic diversity, while Sorotonan demonstrated reduced species richness and increased dominance of species such as Elaeis guineensis. Mixed models substantiated that plantation area was the principal determinant of floristic diversity, with notable effects observed from 2 hectares onwards. Neither plantation age nor distance from the MSNP exhibited robust influences. The cultivated area predominantly shapes floristic diversity in cashew plantations surrounding MSNP. Integrated land management that encourages diversified agroforestry practices over larger plots appears critical for harmonizing sustainable agricultural production with biodiversity conservation.