Marine mixotrophy increases trophic transfer efficiency, mean organism size, and vertical carbon flux

Mixotrophic plankton, which combine the uptake of inorganic resources and the ingestion of living prey, are ubiquitous in marine ecosystems, but their integrated biogeochemical impacts remain unclear. We address this issue by removing the strict distinction between phytoplankton and zooplankton from...

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Bibliographic Details
Main Authors: Ward, Ben A., Follows, Michael J
Other Authors: Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences
Format: Article
Language:en_US
Published: National Academy of Sciences (U.S.) 2016
Online Access:http://hdl.handle.net/1721.1/104937
https://orcid.org/0000-0002-3102-0341
Description
Summary:Mixotrophic plankton, which combine the uptake of inorganic resources and the ingestion of living prey, are ubiquitous in marine ecosystems, but their integrated biogeochemical impacts remain unclear. We address this issue by removing the strict distinction between phytoplankton and zooplankton from a global model of the marine plankton food web. This simplification allows the emergence of a realistic trophic network with increased fidelity to empirical estimates of plankton community structure and elemental stoichiometry, relative to a system in which autotrophy and heterotrophy are mutually exclusive. Mixotrophy enhances the transfer of biomass to larger sizes classes further up the food chain, leading to an approximately threefold increase in global mean organism size and an ∼35% increase in sinking carbon flux.