Impact of Soil Heterogeneity on Forest Structure and Diversity of Tree Species in the Central Congo Basin

Premise of research. The role of soil in shaping plant communities in forest ecosystems has long attracted scientific interest, and many studies have pointed out the importance of edaphic properties on species distributions within the tropics. There is still a need to investigate whether edaphic differentiation affects forest composition and structure and to assess which soil properties can be good predictors of potential differences in species diversity.Methodology. We established 24 1-ha plots in nondisturbed semideciduous forests in the Central Congo Basin, following clear-cut edaphic heterogeneity between sandy soils and clayey substrates. All individual trees with ≥10-cm diameter at breast height were inventoried in order to account for the diametric structures of trees and patterns of their diversity.Pivotal results. Sandy and clayey plots differed significantly in their soil physical and chemical properties. Soil clearly segregates tree species into sand community and clay community, with species a...