Marine science professor Dr. Mark Green has been awarded a $500,000 National Science Foundation grant to continue his research related to ocean acidification. The new grant will fund research in Maine estuaries, where he will study effects of acidification on juvenile clams. The study will lead to a better understanding of the impacts of various acid burdens on this valuable commercial fishery in river-influenced coastal environments. Results from the study will also be used to develop a diagnostic model that will help the shellfish management community better predict future recruitment success of commercially important bivalve populations in coastal Maine.
Estuaries like Casco Bay in the Gulf of Maine and Chesapeake Bay are typically less buffered to acid than the open ocean because of inputs from the land, the atmosphere and internal aquatic mechanisms. In these locations, changes in acidification happen much faster, making them the best environment to study the effects of acid burdens, some of which are due to increased carbon dioxide in the atmosphere and groundwater runoff. Green's previous research proved that in more acidic sediment, the shells of juvenile clams dissolve, leading to massive die off of the young. He has also discovered that some juvenile clams will not even burrow in mud that is too acidic, leaving them exposed to predators. The current work will evaluate management strategies aimed at lowering the acid concentrations in coastal sediment, thereby increasing settlement of juveniles and populations of adult bivalves.