Plant-pollinator networks and fragmented landscapes: does plants' breeding system matter?

ASTEGIANO JULIA; GUIMARAES PAULO ROBERTO JR

Bonito (Mato Grosso)

Simposio; 49th Annual Meeting of the Association for Tropical Biology and Conservation (ATBC); 2012

Breeding system (BS) determines the degree of dependence of plants on pollinators for pollen deposition modulating species vulnerability to pollinator decline. Therefore, the evaluation of the relationship between BS and species attributes in plant-pollinator networks may improve our understanding of community fragility to species loss in fragmented habitats. We examined whether species degree (k), nestedness (Ni), within module degree (Zi) and among-module connectivity (Ci) differ among autonomous self-pollination, dioecious, self-compatible non-autonomous and self-incompatible plants, in a plant-pollinator network from a fragmented landscape. Plant breeding systems were assigned following results from field studies and from the literature. Autonomous self-pollination and dioecious species showed higher degree than self-compatible non-autonomous and self-incompatible plants. Moreover, the formers had higher values of Ni than self-compatible non-autonomous species. Contrary, Zi and Ci did not differ among groups. Autonomous self-pollination and dioecious species were network hubs (species with high Zi and Ci), whereas self-compatible non autonomous plants were mainly peripherals (species with low Zi and Ci). In addition of being network hubs and showing higher degree and Ni, autonomous self-pollination species are low pollinator-dependent plants, resulting in potentially higher network robustness to pollinator loss. Likely, dioecious plants (i.e. high pollinator-dependent) might buffer pollinator decline by interacting with many species and thus contribute to network robustness. However, the loose of particular pollinators interacting with self-compatible and self-incompatible plants might have a high negative impact on species and interaction diversity.