Sources, Sinks and Subsidies of Carbon within Coastal Saltmarsh Habitats

Saltmarshes are vegetated intertidal ecosystems that support unique biodiversity and provide coastal protection from storms and floods, alongside other ecosystem services. They accrete organic carbon through accumulation of in-situ plant material and trapping of sediments during tidal flux. Saltmarshes can accumulate carbon at rates much faster than terrestrial forests, and for store it much longer. Thus, saltmarshes can contribute to mitigating climate change, but further work is required to determine how they cycle carbon. This research aims to use extensive field and lab-work, using novel methods, to improve our understanding of the fates of the different sources of organic carbon once accumulated into Scottish saltmarshes. It is hypothesised that the younger, in-situ material will be preferentially respired, and the older, more stable, trapped material will be stored for longer.
My research will inform work to include saltmarshes in the UK's greenhouse gas inventory. It will help to highlight which saltmarshes could be targeted for management to maximise carbon storage and climate mitigation. It will contribute to a slim but important evidence base for emissions from saltmarshes, which is vital for understanding how they balance as carbon sources/sinks and fit into the global carbon cycle, and to improve carbon accounting accuracy.