Salt marshes are places where mud and plants gradually build up layers, quietly locking away carbon that would otherwise enter the atmosphere and this natural storage plays an important role in nutrient cycling. But what ensures that this buried carbon stays safely stored over centuries and could that change as our environment shifts?

We are studying the hidden world beneath salt marshes on the Massachusetts coast by collecting deep soil cores and examining both the kinds of organic material present and the tiny microbes at work. Using genetic tools, we identify which microbes are active and what roles they play in breaking down or preserving different types of carbon. We also use a specialized chemical technique called NMR that acts like a molecular “scanner,” helping us see whether the carbon is made up of simpler plant materials or more resistant, woody substances.

By linking these detailed carbon “recipes” with the microbial workforce responsible for processing them, we hope to understand not just what is happening underground, but why. This research helps us know whether salt marshes will continue to act as reliable natural carbon sinks in a changing world.