| Dynamic Green Ocean Project |
Laboratory based biological oceanography
TITLE: Influence of microzooplankton on the phytoplankton community structure.
SUPERVISOR & CO-SUPERVISOR
Erik Buitenhuis
University of East Anglia (UEA)
PROJECT DESCRIPTION
Microzooplankton graze 57 - 75 % of primary production (Calbet and Landry, 2004).
Thus, they constitute the most significant loss term for phytoplankton.
Microzooplankton prefer phytoplankton that are ~8 times smaller in diameter than themselves (Straile 1997).
Thus, depending on the size distribution of the microzooplankton,
they will influence the size distribution of the phytoplankton.
This in turn will affect the functioning of the marine ecosystem
and the associated biogeochemical cycles.
Food preference by microzooplankton has been studied before,
but a lot of data is needed to get an accurate global representation of microzooplankton as a plankton functional type (PFT) (cf. Buitenhuis et al. 2006 on mesozooplankton).
In this project, the aim is to better constrain food preference by microzooplankton with new laboratory grazing experiments,
complemented by published rates of
field measurements of microzooplankton ingestion (Buitenhuis et al. 2010)
and of laboratory experiments (Sailley et al. in preparation, Sailley PhD thesis).
General background
We are a modelling group who investigate the feedback between climate and the oceanic carbon cycle through the structure of the marine ecosystem.
The most recent climate models include representations of ecosystem
processes, both on land and in the oceans. Ecosystem processes are now
seen as vital to a better understanding of the various climate
feedbacks.
Here we propose to investigate the feedback between
climate and the oceanic carbon cycle through the microbial loop and the
structure of the phytoplankton community.
Currently, our group has
5 laboratory based PhD students who do experimental
work (~75%), data synthesis (~15%) and modelling (~10%) to improve the
representation of physiological characteristics of specific plankton groups.
This work
will be undertaken in the framework of the Dynamic Green Ocean Project,
an international project aimed at developing a community model of
ocean biogeochemistry for applications to Earth system problems.
Work plan
During the laboratory work the incumbent will cultivate ~ 10 species of microzooplankton and
test their ingestion and growth rates with different foods.
This will constitute the main part of the project.
Depending on the interest of the candidate,
this could be extended with a limited effort in doing sensitivity analysis of the model, using the results of the experiments,
or a more extensive effort in introducing different formulations of food preference in the model,
with the analysis of oceanographic observations for model validation,
and with interactions with global climate change.
The incumbent will work as part of a small but dynamic and
highly international group and in collaboration with a worldwide
network of marine ecologists and ocean modelers.
Profile of the candidate: At present there are no cultures of microzooplankton at UEA, and no expertise in microzooplankton grazing experiments, so we are looking for a candidate who already has that expertise. This project could be either carried out at the PhD or post-doctoral level.
Funding: We are seeking a candidate for this project to apply for funding. A candidate for a PhD could apply for funding from the School of Environmental Sciences.
How to apply: Please contact Erik Buitenhuis. See also the extra guidance notes for PhD students.