Scientists scuba dive for core samples to learn the fate of mercury.
Pat Megonigal and Research Technician Jim Duls setting a soil elevation table in the marsh.

 

This story first appeared in the SERC quarterly Newsletter summer 2006

Going Underground

As the CO2 field experiment at SERC enters its third decade, biogeochemist Pat Megonigal prepares to take the operation underground.

Although 20 years of research has shown that elevated CO2 stimulates marsh plants to grow and take up additional carbon, no one knows exactly where the extra carbon goes. It's unknown whether it is stored in the marsh, in the soil for instance, or if it's somehow leaving the ecosystem and cycling back into the atmosphere. Megonigal's earlier studies suggest that the soil isn't growing any denser with carbon, but the marsh is rising. Perhaps the excess carbon introduced to the study sites is going into the soil to produce peat and raising soil elevation.

In a major new undertaking, Megonigal and his team are placing 20 new chambers on the site and outfitting the plots with surface elevation tables, extremely sensitive instruments that can measure the rise in soil surface level. Over the next few years, Megonigal will be monitoring the elevation of the marsh and trying to understand below-ground processes that accumulate and cycle carbon in the marsh ecosystem.
 

For more information, or to reach Dr. Megonigal, please contact SERC science writer Kristen Minogue.