Can we restore Blue Carbon? - Assessing carbon dynamics in restored UK salt marshes through molecular tools

Background: Coastal vegetated ecosystems have recently received much attention for their contribution to climate change mitigation. Especially the high rates of carbon sequestration have been highlighted for these so-called 'Blue Carbon' ecosystems. In the UK these include salt marshes, which could be very relevant in future carbon crediting schemes.

This led to a strong interest in the restoration of salt marshes using managed realignment (i.e. the opening of seawalls to re-introduce tides) to create new carbon sinks.

But do these restored marshes function as a carbon sink in the same way as natural marshes? To answer this question, we need to understand the underlying processes in relation to carbon dynamics and microbial ecology in restored marshes, because microbial decomposition is a main driver of carbon loss.

Research methodology: You will combine methods from the fields of salt marsh restoration, biogeochemistry, and microbial ecology. First, to quantify carbon stocks and sequestration rates, you will collect soil cores from multiple restoration sites in the UK for carbon analysis and dating (using micropaleontology). Second, you will compare the biogeochemistry and microbial ecology of a natural and restored marsh using cutting edge molecular microbial ecology techniques.

Finally, to identify which microbial groups are responsible for actively breaking down organic carbon into CO2 again, you will set up a microcosm lab experiment using soil from the study site and a 13C organic carbon compound as a tracer.