Skip to content


Biological cycling of N-osmolytes in the surface ocean (N-osmolytes)

Dr Beale and Dr Airs preparing samples for measurement of N-Osmolytes in seawater at PML.

Completed project

Project start: November 2014  |  Project end: March 2018
Funder: Natural Environment Research Council (NERC)
Principal Investigator: Dr Ruth Airs
Other participants from PML: Dr Luca Polimene, Dr Rachael Beale

In the ocean, nitrogen-containing compounds are thought to be an important part of the soup of compounds that affect cloud formation, and therefore climate. However, little is currently known about the concentration of these compounds or how they are metabolised by bacteria within the marine water column.

These compounds exist in abundance within marine organisms, which they use to cope with changes in the marine environment (such as increasing salinity in the water). Frequently these compounds are released by organisms into the sea water, for example viral attack or grazing.

Once released, the ‘nitrogenous osmolytes’, or ‘N-osmolytes’ serve as important nutrients for marine microorganisms, which can use them as carbon, nitrogen and energy sources. Furthermore, once broken down and degraded within the ocean, these N-osmolytes contribute to the release of gases, some of which are vital sources of aerosols in the marine atmosphere, which help to reflect sunlight and cause a cooling effect of the climate.

In order to better comprehend the role of N-osmolytes in marine biogeochemical cycles and future climate change scenarios, PML scientists in collaboration with the University of Warwick are embarking on a new three year project, funded by the Natural Environment Research Council (NERC).

The scientists hope to fill in current knowledge gaps through undertaking regular in-situ sampling in surface seawater from the English Channel, to be studied in a laboratory environment with newly developed analytic techniques for measuring N-osmolytes, and to determine which micro-organisms use them, how they use them, and how quickly. The resulting data will also be incorporated into a model for prediction of biogeochemical cycles of N-osmolytes under the influence of future climate change.

The project is expected to further strengthen the UK as a leading country not only in the research of marine biogeochemical cycles and marine microbiology, but also in the development of cutting edge technology in environmental science.