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ENV East Doctoral Training Partnership


Applications to the EnvEast Doctoral Training Partnership are now closed.

Below you can browse some of the PhD projects we have previously funded; if you would like to be informed when applications open, or if you have any questions about EnvEast and our application process, please email us.

Projects previously funded by EnvEast


Exploring the micro-environment around marine algae – impacts on photosynthesis and response to ocean acidification (WHEELER_EMBA15EE)

Project description

Marine phytoplankton are unicellular organisms that are responsible for about half of global photosynthesis. These algae have to use a carbon concentrating mechanism to acquire sufficient CO2 as there is not enough CO2 available at the alkaline pH of seawater. In some large phytoplankton species, high rates of carbon uptake may deplete CO2 around the cell and cause significant changes in pH at the cell surface. These pH changes can tell us how small and large phytoplankton cells use different mechanisms to acquire CO2 for photosynthesis. These different mechanisms are likely to play a central role in the response of phytoplankton communities to future changes in ocean pH due to the burning of fossil fuels.

Project aims:

  1. Use pH microelectrodes to measure light-dependent changes in pH in the cellular microenvironment around different phytoplankton cells;
  2. Determine how the cellular microenvironment influences photosynthetic carbon uptake;
  3. Examine how future changes in ocean pH will influence processes in the cellular microenvironment.

The project will use cutting-edge techniques to determine how a physical constraint (i.e. the diffusive boundary layer) contributes to differing physiologies of phytoplankton species (i.e. between small and large cells) that are likely to play an important role in the response of these communities to future environmental change.

The project will use custom-made pH microelectrodes to measure pH in the microenvironment around a phytoplankton cell. Phytoplankton cells typically range in size from 5-200 µm, so commercially available pH meters are too large. The pH microelectrodes will be used in conjunction with other physiological techniques (e.g. chlorophyll fluorimetry to measure photosynthetic electron transport), molecular techniques (e.g. qPCR to measure gene expression) and imaging approaches (e.g. fluorescent microscopy) to measure intracellular pH. The multi-disciplinary techniques used within this project will result in a broad transferable skill set.

The project will be supervised by Dr Glen Wheeler (Marine Biological Association, Plymouth), and co-supervised by Prof Colin Brownlee (MBA), Prof Richard Geider (Essex) and Dr Tracy Lawson (Essex). The student will join a vibrant multi-disciplinary team of researchers developing innovative approaches to environmental research, and will be registered for a PhD in the School of Biological Sciences at the University of Essex.


Prof Colin Brownlee (Marine Biological Association of the UK)

Prof Richard Geider (School of Biological Sciences, University of Essex)

Dr Tracy Lawson (School of Biological Sciences, University of Essex)

  • Start date 1 October 2015