Influence of landscape structure on pollinator diversity and coffee pollination effectiveness

Author(s)

Fernanda Teixeira Saturni

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Biociências
• Defense date: 05 maio 2015

Examining board members

Jean Paul Walter Metzger; Sebastian Tobias Meyer; Isabel Alves dos Santos; Blandina Felipe Viana

• Advisor: Jean Paul Walter Metzger; Rodolfo Jaffe Ribbi

Abstract

Although several studies have shown that the presence of bees results in increased crop yields, the mechanisms that determine pollination effectiveness on broader spatial scales are still largely unknown. We evaluated the influence of landscape composition and configuration 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 pollination effectiveness in 15 coffee trees per landscape. Pollination effectiveness was measured by counting and weighing the fruit set. We also sampled the bees visiting coffee flowers. Our analyses were made at the landscape level, with 1 and 2 km radii, and at the coffee tree level, with 300 m radius around each tree. We collected 241 bee individuals and identified a total of 22 species. The honeybee Apis mellifera (Apini) was the most abundant species followed by Trigona spinipes (Meliponini). Honeybee abundance was affected by landscape matrix composition while native bee community composition changed with distance to the nearest forest fragment. The presence of bees resulted in an increase in coffee fruit set of 28%. A. mellifera abundance positively affected fruit set at both levels, while the composition of the native bee community affected fruit set differently at the landscape level than at the tree level. Landscape structure was found to affect the community composition of floral visitors, and coffee flowers exposed to bees showed an increase in fruit set compared to flowers excluded from pollinators. Although our results do not allow disentangling the mechanisms responsible for the observed increase in fruit set, our work shows that bee pollination services can be affected by landscape structure. These findings can be used in conservation and agricultural planning to maximize crop production while safeguarding biodiversity and the provision of pollination services. (AU)

• FAPESP's process: 13/17161-7 - Pollinator's diversity and pollination effectiveness of coffee in landscapes with different amounts of forest cover
• Grantee: Fernanda Teixeira Saturni
• Support type: Scholarships in Brazil - Master