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Abstract Ecological restoration often targets plant community recovery, but restoration success may depend on the recovery of a complex web of biotic interactions to maintain biodiversity and promote ecosystem services. Specifically, management that drives resource availability, such as seeding richness and provenance, may alter species interactions across multiple trophic levels. Using experimentally seeded prairies, we examine three key groups—plants, pollinators and goldenrod crab spiders (Misumena vatia, predators of pollinators)—to understand the effects of species richness and admixture seed sourcing of restoration seed mixtures on multitrophic interactions.Working with prairie plants, we experimentally manipulated seed mix richness and the number of seed source regions (single‐source region or admixture seed sourcing). In each experimental prairie, we surveyed floral abundance and richness, pollinator visitation and plant–M. vatiainteractions.A high richness seed mix increased floral abundance when seeds were sourced from a single geographic region, and floral abundance strongly increased pollinator visitation,M. vatiaabundance and prey capture. Seeding richness and admixture seed sourcing of the seed mixture did not affect floral species richness, but floral species richness increased pollinator visitation.Pollinators interacted with different floral communities across seeding treatments, indicating a shift in visited floral species with restoration practices.Synthesis and applications. Long‐term success in prairie restoration requires the restoration of plant–arthropod interactions. We provide evidence that seed mix richness and admixture seed sourcing affect arthropod floral associations, but effective restoration of plant–arthropod interactions should consider total floral resource availability. Incorporating a food web perspective in restoration will strengthen approaches to whole ecosystem restoration.
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Community context mediates effects of pollinator loss on seed production
Abstract A critical goal for ecologists is understanding how ongoing local and global species losses will affect ecosystem functions and services. Diversity–functioning relationships, which are well‐characterized in primary producer communities, are much less consistently predictable for ecosystem functions involving two or more trophic levels, particularly in situations where multiple species in one trophic level impact functional outcomes at another trophic level. This is particularly relevant to pollination functioning, given ongoing pollinator declines and the value of understanding pollination functioning for single plant species like crops or threatened plants. We used spatially replicated, controlled single‐pollinator‐species removal experiments to assess how changes in bumble bee species richness impacted the production of fertilized seeds in a perennial herb—Delphinium barbeyi—in the Rocky Mountains of Colorado, USA. To improve predictability, we also assessed how traits and abundances in the plant and bumble bee communities were related toD. barbeyireproductive success. We hypothesized that trait‐matching between pollinator proboscis length andD. barbeyi's nectar spurs would produce a greater number of fertilized seeds, while morphological similarity within the floral community would dilute pollination services. We found that the effects of pollinator removal differed depending on the behavioral patterns of pollinators and compositional features of the plant and pollinator communities. While pollinator floral fidelity generally increasedD. barbeyiseed production, that positive effect was primarily evident when more than half of theBombuscommunity was experimentally removed. Similarly, communities comprising primarily long‐tongued bees were most beneficial toD. barbeyiseed production in tandem with a strong removal. Finally, we observed contrasting effects of morphological similarity in the plant community, with evidence of both competition and facilitation among plants. These results offer an example of the complex dynamics underlying ecosystem function in multitrophic systems and demonstrate that community context can impact diversity–functioning relationships between trophic levels.
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- Award ID(s):
- 2129759
- PAR ID:
- 10421087
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Ecosphere
- Volume:
- 14
- Issue:
- 6
- ISSN:
- 2150-8925
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Ecological restoration often targets plant community recovery, but restoration success may depend on the recovery of a complex web of biotic interactions to maintain biodiversity and promote ecosystem services. Specifically, management that drives resource availability, such as seeding richness and provenance, may alter species interactions across multiple trophic levels. Using experimentally seeded prairies, we examine three key groups – plants, pollinators, and goldenrod crab spiders (Misumena vatia, predators of pollinators) – to understand the effects of species richness and admixture seed sourcing of restoration seed mixtures on multi-trophic interactions. Working with prairie plants, we experimentally manipulated seed mix richness and the number of seed source regions (single-source region or admixture seed sourcing). In each experimental prairie, we surveyed floral abundance and richness, pollinator visitation, and plant-M. vatia interactions. A high-richness seed mix increased floral abundance when seeds were sourced from a single geographic region, and floral abundance strongly increased pollinator visitation, M. vatia abundance, and prey capture. Seeding richness and admixture seed sourcing of the seed mixture did not affect floral species richness, but floral species richness increased pollinator visitation. Pollinators interacted with different floral communities across seeding treatments, indicating a shift in visited floral species with restoration practices. Synthesis and applications. Long-term success in prairie restoration requires the restoration of plant-arthropod interactions. We provide evidence that seed mix richness and admixture seed sourcing affect arthropod floral associations, but effective restoration of plant-arthropod interactions should consider total floral resource availability. Incorporating a food web perspective in restoration will strengthen approaches to whole ecosystem restoration.more » « less
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