Floral resource-landscapes and pollinator-mediated interactions in plant communities

Henning Nottebrock; Baptiste Schmid; Katharina Mayer; Céline Devaux; Karen J. Esler; Katrin Boehning-Gaese; Matthias Schleuning; Jörn Pagel; Frank Schurr

doi:10.1101/022533

bioRxiv · 10.1101/022533

Floral resource-landscapes and pollinator-mediated interactions in plant communities

Henning Nottebrock·Baptiste Schmid·Katharina Mayer·Céline Devaux·Karen J. Esler·Katrin Boehning-Gaese·Matthias Schleuning·Jörn Pagel·Frank Schurr

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Abstract

Plant communities provide floral resource-landscapes for pollinators. Yet, it is insufficiently understood how these landscapes shape pollinator-mediated interactions among multiple plant species. Here, we study how pollinators and the seed set of plants respond to the distribution of a floral resource (nectar sugar) in space and across plant species, inflorescences and flowering phenologies. In a global biodiversity hotspot, we quantified floral resource-landscapes on 27 sites of 4 ha comprising 127,993 shrubs of 19 species. Visitation rates of key bird pollinators strongly depended on the phenology of site-scale resource amounts. Seed set of focal plants increased with resources of conspecific neighbours and with site-scale resources, notably with heterospecific resources of lower quality (less sugar per inflorescence). Floral resources are thus a common currency determining how multiple plant species interact via pollinators. These interactions may alter conditions for species coexistence in plant communities and cause community-level Allee effects that promote extinction cascades.

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Henning Nottebrock, Baptiste Schmid, Katharina Mayer, Céline Devaux, Karen J. Esler, Katrin Boehning-Gaese, Matthias Schleuning, Jörn Pagel, Frank Schurr. 2015-07-16. Floral resource-landscapes and pollinator-mediated interactions in plant communities. https://doi.org/10.1101/022533

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