Nanoparticle pollution has been shown to affect various organisms. However, the effects of nanoparticles on species interactions, and the role of species traits, such as body size, in modulating these effects, are not well‐understood. We addressed this issue using competing freshwater phytoplankton species exposed to copper oxide nanoparticles. Increasing nanoparticle concentration resulted in decreased phytoplankton species growth rates and community productivity (both abundance and biomass). Importantly, we consistently found that nanoparticles had greater negative effects on species with smaller cell sizes, such that nanoparticle pollution weakened the competitive dominance of smaller species and promoted species diversity. Moreover, nanoparticles reduced the growth rate differences and competitive ability differences of competing species, while having little effect on species niche differences. Consequently, nanoparticle pollution reduced the selection effect on phytoplankton community abundance, but increased the selection effect on community biomass. Our results suggest cell size as a key functional trait to consider when predicting phytoplankton community structure and ecosystem functioning in the face of increasing nanopollution.
The cumulative outcome of bacteria-phytoplankton cell-cell interactions has global-scale consequences that necessitate a more comprehensive understanding of the species that form these relationships, the chemical exchanges that govern them, and the chemical cues that trigger them. However, the diffuse liquid environment supporting these exchanges is inherently difficult to interrogate, which has moved researchers to combine multi-omics analyses, genome mining tools, genetic probes, and mathematical models to gain insight into the species and chemical networks existing around individual phytoplankton cells. Yet, fundamental questions still remain about these micro-scale interactions, creating an opportunity for innovating new methods where biology and chemistry interface with engineering and mathematics.
more » « less- PAR ID:
- 10483053
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Integrative And Comparative Biology
- Volume:
- 63
- Issue:
- 6
- ISSN:
- 1540-7063
- Format(s):
- Medium: X Size: p. 1509-1519
- Size(s):
- p. 1509-1519
- Sponsoring Org:
- National Science Foundation
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