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Abstract Background and Aims When plant communities are exposed to herbicide ‘drift’, wherein particles containing the active ingredient travel off-target, interspecific variation in resistance or tolerance may scale up to affect community dynamics. In turn, these alterations could threaten the diversity and stability of agro-ecosystems. We investigated the effects of herbicide drift on the growth and reproduction of 25 wild plant species to make predictions about the consequences of drift exposure on plant-plant interactions and the broader ecological community. Methods We exposed potted plants from species that commonly occur in agricultural areas to a drift-level dose of the widely used herbicide dicamba or a control solution in the glasshouse. We evaluated species-level variation in resistance and tolerance for vegetative and floral traits. We assessed community-level impacts of drift by comparing species evenness and flowering networks of glasshouse synthetic communities comprised of drift-exposed and control plants. Key Results Species varied significantly in resistance and tolerance to dicamba drift: some were negatively impacted while others showed overcompensatory responses. Species also differed in the way they deployed flowers over time following drift exposure. While drift had negligeable effects on community evenness based on vegetative biomass, it caused salient differences in the structure of coflowering networks within communities. Drift reduced the degree and intensity of flowering overlap among species, altered the composition of groups of species that were more likely to coflower with each other than with others, and shifted species roles (e.g., from dominant to inferior floral producers and vice versa). Conclusions These results demonstrate that even low levels of herbicide exposure can significantly alter plant growth and reproduction, particularly flowering phenology. If field-grown plants respond similarly, then these changes would likely impact plant-plant competitive dynamics and potentially plant-pollinator interactions occurring within plant communities at the agro-ecological interface.
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Sex‐associated differences in the network roles of pollinators
Abstract Sex‐associated differences in behavior can have large ecological consequences, especially in plant–pollinator communities where floral visitor behavior affects plant reproduction. Whether these differences are prevalent enough to impact community‐level processes, however, is unknown. Using 256 plant–pollinator communities, we built networks where the floral interactions of each sex were modeled separately, comparing observations to simulated networks where sex was randomized. We found that (1) in many species the sexes differed in their network roles and visited different partners, with females tending to visit more species and more peripheral species than males; (2) more generalist species differed more in network roles between the sexes; and (3) networks where nodes were separated by sex were more specialized than simulated networks, but were similarly resistant to perturbations. These findings suggest that despite variation among species, sex‐associated differences in behavior are large enough to impact the network roles of male and female pollinators and common enough to influence the interaction patterns of entire plant–pollinator communities.
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- Award ID(s):
- 2009075
- PAR ID:
- 10610192
- Publisher / Repository:
- Wiley Online Library
- Date Published:
- Journal Name:
- Ecosphere
- Volume:
- 12
- Issue:
- 12
- ISSN:
- 2150-8925
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/ecs2.3863
