Marine Biogeochemistry

About our research

Our interdisciplinary research is based around 5 major themes.

Primary production

We research chemical, biological and physical controls on primary production in the surface ocean. 

The ocean is responsible for about half of global primary production. It is a major absorber of the atmospheric carbon dioxide (CO2) released by human activities. 

Key research questions

  • What controls the flow of energy from the sun into ocean ecosystems? 
  • What are the controls on phytoplankton distributions and productivity? 
  • How do bioactive trace elements (Fe, Zn, Co) drive or limit primary production in the surface ocean?
  • How does availability of iron control nitrogen fixation?
  • How does resource limitation (for example availability of light and nutrients) restrict the activity of marine phytoplankton and the biogeochemical processes they influence?

The 'twilight zone'

We investigate the mesopelagic ocean, known as the 'twilight zone'. We explore its processes and the vertical export of materials into the ocean's interior.

This zone is a critical buffer zone between the sunlit surface and the dark deep ocean. It intercepts all material transfers from the surface into the deep. This includes the particles that drive the biological carbon pump (BCP). The BCP is a principal method of CO2 sequestration.

Key research questions

  • Is remineralisation of organic matter the same for all nutrients in the mesopelagic ocean?
  • Are suspended particles remineralised the same way as sinking particles?
  • Are the microbial communities the same between those associated with sinking particles and those with suspended particles?
  • How exactly is nitrogen regenerated from organic matter in the twilight ocean?

Biogeochemical cycles

We research biogeochemical cycles and their response to global environmental changes.

Many elemental cycles are intimately linked and interact through life processes. They are sensitive to ongoing global environmental changes. We have a track record of leading the pelagic component of the UK Ocean Acidification Research Programme (UKOARP)

Key research questions

  • How is climate change altering the biogeochemistry of the polar oceans?
  • What are the key sources and sinks of trace elements?
  • How does resource limitation (for example availability of light and nutrients) restrict the activity of marine phytoplankton and the biogeochemical processes they influence? 
  • What are the linkages between ocean biogeochemical processes and climate variability?
  • How is ocean biogeochemistry currently changing and has been through Earth history?

Marine planktonic and microbial communities

We study the dynamics of marine planktonic and microbial communities.

Marine microbes are master cyclers of many elements in the ocean. They are responsible for about half of global primary production by turning CO2 into organic matter that feeds the marine ecosystems. 

Key research questions

  • What are the main drivers of observed microbial diversity in the ocean?
  • How does organism size regulate physiology and ecosystem function?
  • How do fundamental microbial traits dictate large-scale ecosystem function?
  • What are the controls on phytoplankton species distributions and productivity? 
  • When do metabolically versatile microbes switch functions?
  • Is it syntrophy or parasitism?
  • When and where are the harmful algal blooms occurring?

Algal biofuel and other biotechnologies

We study the development of photosynthetic microbes for algal biofuel and other biotechnologies.

Key research questions

  • Can photosynthetic microbes be developed as platforms for the sustainable development of useful compounds?
  • Can microorganisms be applied to enhance weathering to capture CO2?