Landscape structure influences bee community and coffee pollination at different spatial scales

摘要

Although several studies have shown that the presence of bees results in increased crop yields, the mechanisms that determine pollination service across different spatial scales are still largely unknown. Here, we evaluated the influence of landscape structure over bee community composition and coffee (Coffea arabica) pollination. Our study was undertaken in one of the most important coffee-producing regions of Brazil, and comprised nine landscapes of sun coffee plantations surrounded by different amounts of Atlantic Forest remnants. Using floral exclusion experiments we evaluated fruit set in 15 coffee shrubs per landscape. We also sampled the bees visiting coffee flowers. Our analyses were made at two landscape scales, with 1 and 2 km radii, and one shrub scale, with 300 m radius around each coffee shrub. We collected 241 bee individuals and identified a total of 22 species. The honeybee Apis mellifera (Apini) was the most abundant flower visitor followed by Trigona spinipes (Meliponini). Native bee abundance, richness and diversity were positively affected by forest cover at the shrub scale. Honeybee abundance, on the other hand, was negatively affected by forest cover at the shrub scale. The presence of bees resulted in an increase in coffee fruit set of 28%. A. mellifera abundance positively affected fruit set across spatial scales, while the composition of the native bee community affected fruit set differently at the landscape scales than at the shrub scale. Our work shows that bee pollination services are affected by landscape structure at different spatial scales. These findings can be used in conservation and agricultural planning to maximize crop production while safeguarding biodiversity and the provision of pollination services. (C) 2016 Elsevier B.V. All rights reserved.