TY - JOUR
T1 - Defining Planktonic Protist Functional Groups on Mechanisms for Energy and Nutrient Acquisition
T2 - Incorporation of Diverse Mixotrophic Strategies
AU - Mitra, Aditee
AU - Flynn, Kevin J.
AU - Tillmann, Urban
AU - Raven, John A.
AU - Caron, David
AU - Stoecker, Diane K.
AU - Not, Fabrice
AU - Hansen, Per J.
AU - Hallegraeff, Gustaaf
AU - Sanders, Robert
AU - Wilken, Susanne
AU - McManus, George
AU - Johnson, Mathew
AU - Pitta, Paraskevi
AU - Våge, Selina
AU - Berge, Terje
AU - Calbet, Albert
AU - Thingstad, Frede
AU - Jeong, Hae Jin
AU - Burkholder, JoAnn
AU - Glibert, Patricia M.
AU - Granéli, Edna
AU - Lundgren, Veronica
N1 - This work was funded by grants to KJF and AM from the Leverhulme Trust (International Network Grant F00391V) and NERC (UK) through its iMARNET programme NE/K001345/1.
PY - 2016/4
Y1 - 2016/4
N2 - Arranging organisms into functional groups aids ecological research by grouping organisms (irrespective of phylogenetic origin) that interact with environmental factors in similar ways. Planktonic protists traditionally have been split between photoautotrophic "phytoplankton" and phagotrophic "microzooplankton". However, there is a growing recognition of the importance of mixotrophy in euphotic aquatic systems, where many protists often combine photoautotrophic and phagotrophic modes of nutrition. Such organisms do not align with the traditional dichotomy of phytoplankton and microzooplankton. To reflect this understanding, we propose a new functional grouping of planktonic protists in an eco-physiological context: (i) phagoheterotrophs lacking phototrophic capacity, (ii) photoautotrophs lacking phagotrophic capacity, (iii) constitutive mixotrophs (CMs) as phagotrophs with an inherent capacity for phototrophy, and (iv) non-constitutive mixotrophs (NCMs) that acquire their phototrophic capacity by ingesting specific (SNCM) or general non-specific (GNCM) prey. For the first time, we incorporate these functional groups within a foodweb structure and show, using model outputs, that there is scope for significant changes in trophic dynamics depending on the protist functional type description. Accordingly, to better reflect the role of mixotrophy, we recommend that as important tools for explanatory and predictive research, aquatic food-web and biogeochemical models need to redefine the protist groups within their frameworks.
AB - Arranging organisms into functional groups aids ecological research by grouping organisms (irrespective of phylogenetic origin) that interact with environmental factors in similar ways. Planktonic protists traditionally have been split between photoautotrophic "phytoplankton" and phagotrophic "microzooplankton". However, there is a growing recognition of the importance of mixotrophy in euphotic aquatic systems, where many protists often combine photoautotrophic and phagotrophic modes of nutrition. Such organisms do not align with the traditional dichotomy of phytoplankton and microzooplankton. To reflect this understanding, we propose a new functional grouping of planktonic protists in an eco-physiological context: (i) phagoheterotrophs lacking phototrophic capacity, (ii) photoautotrophs lacking phagotrophic capacity, (iii) constitutive mixotrophs (CMs) as phagotrophs with an inherent capacity for phototrophy, and (iv) non-constitutive mixotrophs (NCMs) that acquire their phototrophic capacity by ingesting specific (SNCM) or general non-specific (GNCM) prey. For the first time, we incorporate these functional groups within a foodweb structure and show, using model outputs, that there is scope for significant changes in trophic dynamics depending on the protist functional type description. Accordingly, to better reflect the role of mixotrophy, we recommend that as important tools for explanatory and predictive research, aquatic food-web and biogeochemical models need to redefine the protist groups within their frameworks.
KW - Microzooplankton
KW - Mixotroph
KW - Phagotroph
KW - Phototroph
KW - Phytoplankton
KW - Plankton functional types (PFTs)
UR - http://www.scopus.com/inward/record.url?scp=84959214157&partnerID=8YFLogxK
U2 - 10.1016/j.protis.2016.01.003
DO - 10.1016/j.protis.2016.01.003
M3 - Article
C2 - 26927496
AN - SCOPUS:84959214157
SN - 1434-4610
VL - 167
SP - 106
EP - 120
JO - Protist
JF - Protist
IS - 2
ER -