title: Characterizing the phylogenetic tree community structure of a protected tropical rain forest area in Cameroon.
abstract: Tropical rain forests, the richest terrestrial ecosystems in biodiversity on Earth are highly threatened by global changes. This paper aims to infer the mechanisms governing species tree assemblages by characterizing the phylogenetic structure of a tropical rain forest in a protected area of the Congo Basin, the Dja Faunal Reserve (Cameroon). We re-analyzed a dataset of 11538 individuals belonging to 372 taxa found along nine transects spanning five habitat types. We generated a dated phylogenetic tree including all sampled taxa to partition the phylogenetic diversity of the nine transects into alpha and beta components at the level of the transects and of the habitat types. The variation in phylogenetic composition among transects did not deviate from a random pattern at the scale of the Dja Faunal Reserve, probably due to a common history and weak environmental variation across the park. This lack of phylogenetic structure combined with an isolation-by-distance pattern of taxonomic diversity suggests that neutral dispersal limitation is a major driver of community assembly in the Dja. To assess any lack of sensitivity to the variation in habitat types, we restricted the analyses of transects to the terra firme primary forest and found results consistent with those of the whole dataset at the level of the transects. Additionally to previous analyses, we detected a weak but significant phylogenetic turnover among habitat types, suggesting that species sort in varying environments, even though it is not predominating on the overall phylogenetic structure. Finer analyses of clades indicated a signal of clustering for species from the Annonaceae family, while species from the Apocynaceae family indicated overdispersion. These results can contribute to the conservation of the park by improving our understanding of the processes dictating community assembly in these hyperdiverse but threatened regions of the world.
authors.affiliation: Aix Marseille Université, IRD, LPED UMR 151, Marseille, France; Centre de coopération internationale en recherche agronomique pour le développement, UMR AMAP, Montpellier, France.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Manel
authors.affiliation: Institut de Recherche pour le Développement, UMR DIADE, Montpellier, France; Département des Sciences Biologiques, Laboratoire de Botanique Systématique et d'Ecologie, Université de Yaoundé I, Ecole Normale Supérieure, Yaoundé, Cameroon.
authors.forename: Thomas L P
authors.initials: TL
authors.lastname: Couvreur
authors.affiliation: Université Montpellier 2, UMR AMAP, Montpellier, France.
authors.forename: François
authors.initials: F
authors.lastname: Munoz
authors.affiliation: Institut de Recherche Pour le Développement, UMR AMAP, Montpellier, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Couteron
authors.affiliation: Université Libre de Bruxelles, Faculté des Sciences, Evolutionary Biology and Ecology Brussels, Belgium.
authors.forename: Olivier J
authors.initials: OJ
authors.lastname: Hardy
authors.affiliation: Département des Sciences Biologiques, Laboratoire de Botanique Systématique et d'Ecologie, Université de Yaoundé I, Ecole Normale Supérieure, Yaoundé, Cameroon.
authors.forename: Bonaventure
authors.initials: B
authors.lastname: Sonké
mesh_terms: D002163:Cameroon; D003247:Conservation of Natural Resources; D049810:Genetic Speciation; D010802:Phylogeny; D065947:Rainforest; D014197:Trees / Q000145:classification* / Q000235:genetics