O efeito da paisagem na subtribo de abelhas Euglossina (Hymenoptera: Apidae)

Abstract

Deforestation in the Atlantic Forest has been changing the landscape structure for decades in Brazil. To test the hypothesis that landscape structure and fragmentation effects could favor diversity, we developed this study to answer two questions: I) Which structural landscape elements do best explain Euglossine richness in a highly fragmented landscape? What is the critical threshold of natural habitat amount, in respect to long-distance pollinators, in such landscape? Although our region situates in a highly fragmented landscape, structural features, such as natural habitat amount and heterogeneity, in a landscape of 1,000m radius, favored long-distance pollinators. Such pollinators have their diversity maintained in landscapes with percentage of habitat above the 25% natural habitat threshold. Habitat amount and spatial heterogeneity best explained pollinator diversity. Pollinators benefit from larger percentage of habitat and heterogeneity, given the increase in the range of floral resources available and the facility to reach them. For these pollinators, such landscapes represent a diverse range of floral and nest material. We used smell bait to sample Euglossine bees, efficient long-distance pollinators, and analyzed data by regression models. We selected the best model using wAIC from the Akaike Information Criterion, by comparing GLM of landscape structural elements (composition and configuration) and estimated richness of Euglossine bees.