Influence of ocean acidification on plankton community structure during a winter-to-summer succession: An imaging approach indicates that copepods can benefit from elevated CO2 via indirect food web effects.

Taucher, Jan, Haunost, Mathias, Boxhammer, Tim, Bach, Lennart T., Algueró-Muñiz, María and Riebesell, Ulf (2017) Influence of ocean acidification on plankton community structure during a winter-to-summer succession: An imaging approach indicates that copepods can benefit from elevated CO2 via indirect food web effects. PLoS ONE, 12 (2). e0169737. DOI 10.1371/journal.pone.0169737.

[img]
Preview
Text
journal.pone.0169737.pdf - Published Version
Available under License Creative Commons: Attribution 4.0.

Download (1143Kb) | Preview

Supplementary data:

Abstract

Plankton communities play a key role in the marine food web and are expected to be highly sensitive to ongoing environmental change. Oceanic uptake of anthropogenic carbon dioxide (CO2) causes pronounced shifts in marine carbonate chemistry and a decrease in seawater pH. These changes–summarized by the term ocean acidification (OA)–can significantly affect the physiology of planktonic organisms. However, studies on the response of entire plankton communities to OA, which also include indirect effects via food-web interactions, are still relatively rare. Thus, it is presently unclear how OA could affect the functioning of entire ecosystems and biogeochemical element cycles. In this study, we report from a long-term in situ mesocosm experiment, where we investigated the response of natural plankton communities in temperate waters (Gullmarfjord, Sweden) to elevated CO2 concentrations and OA as expected for the end of the century (~760 μatm pCO2). Based on a plankton-imaging approach, we examined size structure, community composition and food web characteristics of the whole plankton assemblage, ranging from picoplankton to mesozooplankton, during an entire winter-to-summer succession. The plankton imaging system revealed pronounced temporal changes in the size structure of the copepod community over the course of the plankton bloom. The observed shift towards smaller individuals resulted in an overall decrease of copepod biomass by 25%, despite increasing numerical abundances. Furthermore, we observed distinct effects of elevated CO2 on biomass and size structure of the entire plankton community. Notably, the biomass of copepods, dominated by Pseudocalanus acuspes, displayed a tendency towards elevated biomass by up to 30–40% under simulated ocean acidification. This effect was significant for certain copepod size classes and was most likely driven by CO2-stimulated responses of primary producers and a complex interplay of trophic interactions that allowed this CO2 effect to propagate up the food web. Such OA-induced shifts in plankton community structure could have far-reaching consequences for food-web interactions, biomass transfer to higher trophic levels and biogeochemical cycling of marine ecosystems.

Document Type: Article
Keywords: Copepods; Plankton; Food web structure; Biomass (ecology); Mesocosms; Phytoplankton; Ocean acidification; Marine ecology
Research affiliation: OceanRep > The Future Ocean - Cluster of Excellence
AWI
OceanRep > GEOMAR > FB2 Marine Biogeochemistry > FB2-BI Biological Oceanography
Kiel University
Refereed: Yes
Open Access Journal?: Yes
DOI etc.: 10.1371/journal.pone.0169737
ISSN: 1932-6203
Projects: BIOACID, Future Ocean
Expeditions/Models/Experiments:
Date Deposited: 28 Feb 2017 13:59
Last Modified: 10 Jul 2017 06:47
URI: http://oceanrep.geomar.de/id/eprint/36724

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...