Diverse pollinator communities enhance plant reproductive success

Abstract

Understanding the functional consequences of biodiversity loss is a major goal of ecology. Animal-mediated pollination is an essential ecosystem function and service provided to mankind. However, little is known how pollinator diversity could affect pollination services. Using a substitutive design, we experimentally manipulated functional group (FG) and species richness of pollinator communities to investigate their consequences on the reproductive success of an obligate out-crossing model plant species, Raphanus sativus. Both fruit and seed set increased with pollinator FG richness. Furthermore, seed set increased with species richness in pollinator communities composed of a single FG. However, in multiple-FG communities, highest species richness resulted in slightly reduced pollination services compared with intermediate species richness. Our analysis indicates that the presence of social bees, which showed roughly four times higher visitation rates than solitary bees or hoverflies, was an important factor contributing to the positive pollinator diversity-pollination service relationship, in particular, for fruit set. Visitation rate at different daytimes, and less so among flower heights, varied among social bees, solitary bees and hoverflies, indicating a niche complementarity among these pollinator groups. Our study demonstrates enhanced pollination services of diverse pollinator communities at the plant population level and suggests that both the niche complementarity and the presence of specific taxa in a pollinator community drive this positive relationship.

Breeding system and pollination of Pleroma trichopodum DC. (Melastomataceae): a potential species for the restoration of Atlantic Forest in southern Brazil

“…Several floral visitors of one species of Tibouchina (T. pulchra), studied by Pereira et al (2011), belonged to three genera also found visiting P. trichopodum, and vary in their relative lengths (size). This trait variation could indicate a certain degree of functional complementarity and enhance the reproductive success of plant communities (Fontaine et al 2006;Albrecht et al 2012). The enhanced attractiveness of high floral display plants to different bees shows that these trees might function as islands of resources (Brito et al 2015) in areas where exotic herbs are dominant.…”

Low functional diversity promotes niche changes in natural island pollinator communities

“…The loss of a given pollinator functional group may impede reproduction of the wild and cultivated plants that depend on the pollinator group, although empirical studies are limited (e.g. [12][13][14][15][16]). …”

Intersection between biodiversity conservation, agroecology, and ecosystem services

“…Blitzer et al (2016) found that functional diversity of bee pollinators explained more variation in apple pollination than species richness, arguably due to increased complementarity with increasing functional richness. Albrecht et al (2012) found that radish fruit and seed set increased with functional group diversity and with increased species richness within single functional group, suggesting the importance of both species specific effects and functional richness. In mesocosm experiments with wild flowers, Frund et al (2013), found that greater coverage of functional niche space predicted seed production better than species richness.…”