Impacts of recruitment limitation and canopy disturbance on tropical tree species richness

We used the process-based forest growth model FORMIND2.0 to show that recruitment limitation and the intermediate disturbance hypothesis which proposes maximum diversity in forests of intermediate disturbance intensity or frequency are both processes which impact on tropical tree species richness. Both processes influence each other and should therefore not be analyzed separately. While on a local level a rise in recruitment limitation promotes species richness, the overall richness of the whole forest declines. Disturbance levels are more important for species richness in forests which are highly limited by recruitment. This study supports previous field data investigations from the Americas. It also highlights the lack of consensus regarding the definition of disturbance and recruitment limitation, which makes inter-study comparisons difficult. (C) 2006 Elsevier B.V. All rights reserved.