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Question What are the conditions necessary for the establishment and development of seedlings and an early stage sapling community in an old-growth cloud forest? Cloud forests are one of the most threatened ecosystems in the world; however, recruitment patterns in these forests remain largely unknown. Location Cloud Forest, Northern Peruvian Andes. Methods We constructed a sapling community model through the unconstrained technique of non-metric multidimensional scaling. We related the distribution of saplings of each species to the distance from conspecific adult (potential parent) trees through a point pattern analysis. We also used zero-inflated Poisson models to investigate the relationship between sapling distributions and environmental conditions and forest structure. Results We found that recruitment in woody plant species tends to be widely spread throughout the forest. The distribution of some sapling species was either positively or negatively related to the position of adult conspecific trees. Several species tended to occur within particular microhabitat conditions, with some differentiation between canopy and understorey species. Conclusions Cloud forest species recruitment may require the cover provided by the forest canopy. Under closed canopy conditions, both dispersal assembly and niche assembly mechanisms appear to simultaneously influence sapling distribution. The different strategies of various species may result in a trade-off between the importance of microhabitat conditions and distance mechanisms, with one prevailing over the other, depending on species and forest structure conditions. [ABSTRACT FROM AUTHOR]

Abstract: The coexistence of a high number of species in the forest is a central issue in tropical ecology. In this paper, we aim to characterise the spatial pattern of woody species in an Andean montane cloud forest to determine whether differences exist among the species in terms of spatial organization and if so, whether these differences are related to the life-form, primary dispersal mode, shade tolerance or the diameter distribution of the species. For this purpose, we analysed the spatial pattern of each species as well as the spatial relationships between young and adult individuals. Almost all the analysed species showed a cluster pattern, followed by a random pattern at larger distances. The cluster size is more evident for the young trees whereas adult trees tended to be more randomly distributed. The shade-tolerant species showed greater distances of aggregation than gap or medium-shade-tolerant species. Species primarily dispersed by wind and small birds showed larger distances of aggregation than species dispersed by mammals or big birds. All the under-story woody plants showed a notable cluster pattern, whereas canopy trees showed a variety of spatial patterns, with clustering at small scales being the most frequent. In the case of emergent trees, association was found between young and adult individuals on a large scale. Positive associations between young and adult individuals predominate at small scales for medium and shade tolerant species and at larger scales for bird-dispersed species whereas negative spatial associations at smaller scales were found for shade tolerant species and wind dispersed species. Our study confirms that conspecific organization varies among the woody plants in the analysed forest, and that the spatial pattern of woody plants is partially linked to shade tolerance, primary dispersal mode and life form of the species. [Copyright &y& Elsevier]