Description
The recently completed NUTS&BOLTS project (http://nutsandboltsproject.ie/ ) was the first study of it’s kind in Ireland to focus on the roles of biogeochemistry and light on shaping the pico and nanoplankton communities found in marine transitional waters on the west coast of Ireland. In this presentation we will briefly outline some of the key findings of our work and how they relate to climate change and the phenomena of coastal darkening.In the estuary of the river Shannon, Ireland’s largest river, flow cytometry measurements found that phycocyanin containing Synechococcus sp. were numerically dominant at the freshwater end, while at the seawater end it was Synechococcus sp. with the pigment phycoerythrin that were most abundant. Hyperspectral measurements of the in situ light attenuation combined with CDOM and particulate absorption observations indicated that a likely driver of this change in Synechococcus sp. was the shift in the light field, moving towards the seaward end of the estuary, from brown to clearer green waters.
Studies in Lough Furnace, a meromictic lagoon which undergoes episodic periods of low oxygen in the bottom waters, revealed the presence of a ‘brown’ green sulfur bacteria (GSB) containing the pigment bacteriochlorophyll e. The GSB were identified through the combination of hyperspectral particulate absorption data and flow cytometry. High CDOM concentrations in the overlying freshwater (draining from nearby peatlands) leads to very low light levels at the pycnocline with a strong red shift compared to the surface.
The field work reported here was supported by the IMBER endorsed project NUTS&BOLTS, co-funded by EPA Research (2018-W-LS-19) and the Marine Institute. Aspects of this work are now being followed up in ISOLUME, a collaborative effort between 11 European partners, supported by the JPI Oceans Changing Marine Lightscapes initiative. ISOLUME has been endorsed by the Intergovernmental Oceanographic Commission (IOC) as part of the UN Ocean Decade of Ocean Science for Sustainable Development 2021-2030.
| Period | 25 Feb 2026 |
|---|---|
| Degree of Recognition | International |