Network of bee-plant interactions and recognition of key species in semideciduous forest

Abstract

Bees are the most effective pollinators of native plants, contributing to the maintenance of many ecosystems, including forests. Studies about networks of bee-plant interactions are critical for conservation and habitat management of native pollinators. This study aimed to determine the richness of flower-visiting bees in a fragment of the Semideciduous Forest (SF) in Uberlândia-MG, identify the plants visited by them and build the bee-plant interactions network in this fragment. The study was conducted between October 2010 and September 2011 along a transect of 200 meters on the edge of the forest, with monthly collections performed from 8:00 am to 2:30 pm. We yielded the bee-plant interaction networks and calculated the NODF index and betweenness centrality. We collected 70 bee species and 25 plant species. The network of interactions was nested (NODF = 10.97, P = 0.03). Apis mellifera Linnaeus and Merremia macrocalyx (Ruiz & Pav.) O'Donell showed the highest centrality. The nestedness of the bee-plant interaction confers stability to the network, demonstrating its importance for the fragment conservation. It is likely that M. macrocalyx is a key species in this network since this plant attracted the highest number of bee species and showed the highest centrality, contributing to network cohesion.