Facilitation allows plant coexistence in Cuban serpentine soils

Serpentine soils represent stressful habitats where plants have to cope with heavy metals, moisture limitation and low nutrient availability. We propose that facilitation is an important mechanism structuring plant communities under such stressful conditions. Facilitation has been shown to generate the spatial association of species, forming discrete vegetation patches of phylogenetically distant species. We measured these spatial and phylogenetic signatures left by facilitation in a serpentine plant community of central Cuba. Our results show that seedlings preferentially grow under plants of different species, and that adults are significantly aggregated into vegetation patches. In these patches, adults tend to co-occur with distant relatives, ultimately forming phylogenetically diverse neighbourhoods. We discuss possible mechanisms explaining how species adapted to serpentine areas may be acting as nurses, reducing the stressful conditions for the establishment of other species. © 2014 German Botanical Society and Royal Botanical Society of the Netherlands.The authors thank all participants on the courses Estructura filogenética de comunidades, developed in Cuba under the CYTED programme (Acción 409AC0369), for fieldwork and discussions. Funding was also provided by AECI (Projects A/016832/08, A017475/08, A023461/09).Peer Reviewe