Evaluating the network structure of different Neotropical plant-plant interactions

摘要

Plant species can be used as hosts by other plant species, both in antagonistic interactions (e.g., parasitism),and in commensal interactions (e.g., epiphytism). In this study, plant-plant interaction networks wereconstructed using the literature available from Brazil in order to contrast networks composed by parasiticversus epiphytic plants. Eight plant-plant networks were analysed: five plant-parasite networks and threeplant-epiphyte networks. The network structure was characterised using the following network metrics:network size, number of interactions, connectance, modularity and nestedness. In total, plant-plant networkscomprised 110 host-plant species and 60 hosted-plant species (parasites or epiphytes) with 269 distinctinteractions. Network size, number of interactions, modularity and nestedness did not differ between differenttypes of networks. On the other hand, network connectance in plant-plant networks was significantly differentbetween habitat types (conserved versus anthropised habitats). The present study represents a pioneersystematic investigation showing that structure of plant-plant networks is influenced by habitat conservationstatus, regardless of the type and the intimacy of interactions between species.