Charlotte investigated photosynthetic
responses of phytoplankton
using a Fast Repetition Rate
UTS Marine Biology (2010) graduate Charlotte Robinson has started 2012 at a cracking pace. An early Christmas present of a First Class Honours degree in Environmental Science has been followed by a UTS PhD Research Scholarship and confirmation of a competitive CSIRO top-up scholarship.
“It has been a very busy time filling out scholarship and research applications but they have all come through and I’ll be officially starting my PhD with the Plant Functional Biology and Climate Change Cluster (C3) at the end of January,” Charlotte said.
Although a Science degree was always in her sights Charlotte completed one year of Forensic Science at UTS before changing to Marine Biology, relishing the opportunity to take part in fieldwork excursions at One Tree and Heron Islands on the Great Barrier Reef.
“As an undergraduate I suspected I wanted to do research. But it was really the exposure to the research projects during the Marine Primary Producers subject, and the work Professor Peter Ralph was doing with chlorophyll fluorescence technology just fascinated me and that lead to my Honours and PhD projects. I knew I wanted to continue with it,” she said.
“The C3 environment is very supportive and the diverse skills of the group mean that I can get help in areas I’m not familiar with, ecosystem modelling for example.”
For her Honours thesis Charlotte studied a phenomena known as the sub-surface chlorophyll maxima (SCM) where phytoplankton grow and thrive at ocean depths seemingly lacking the right conditions for photosynthesis to take place. Not only do they successfully fix carbon at these depths but previous research indicates that the biomass produced here can match or exceed that produced near the surface.
“Not a lot of work has been done on SCMs and there are a range of theories as to why phytoplankton form in the deep layers of the ocean. My Honours research indicates that there is more blue light at these levels and that the spectral quality of the light influences cell physiology and the resultant carbon fixation,” she said.
“My PhD research follows on to some degree in that I’ll still be looking at the physiological and community response of phytoplankton to light, and the ability to fix Carbon, but the focus will be on how these microscopic organisms are partitioned throughout the water column and what the light conditions are, especially in coastal waters."
Coastal waters are “optically complex”; impacted by coastal runoff, substances in coastal waters change how light is absorbed and on a global scale this affects scientists’ ability to decipher reflectance detected by satellite and, subsequently, the accuracy of ocean ecosystem models.
Support from CSIRO via a Wealth from Oceans Flagship top-up scholarship means Charlotte’s research will contribute to developing models for primary production in coastal ecosystems: vital management tools for the maintenance of sustainable coastal ecosystems, fisheries and the general coastal environment.
Charlotte is looking forward to the technology aspect of her project and will use a range of optical equipment including fluorometers and the impressive sounding TRIO S Ramses, a hyperspectral radiometer. Although her fieldwork will generally be concentrated around Sydney Harbour and Port Hacking there is the prospect of a “tropical cruise” from Darwin to Cairns aboard the Southern Surveyor later in 2012.
“I haven’t done an ocean voyage before so an expedition like that would be fantastic,” she said.
Charlotte will also be the Postgraduate Representative on the School of Environment Board in 2012. Looks like the busy times are here to stay for a while yet!
Charlotte’s principal supervisor at UTS is Dr Martina Doblin. She is co-supervised by Professor Peter Ralph and Dr Nagur Cherukuru (CSIRO Land and Water)