Science Serving Maryland's Coasts

Daniela (Pauluzzi) Hammons, Texas A&M University, Galveston

Class Year: 

Project Title: 

The Effects of Shading and Increased Sediment Oxygen Demand on the Non-Structural Carbohydrate Reserves of Zostera marina L.


The abundance and distribution of eelgrass (Zostera marina L.) in Chesapeake Bay have declined in recent decades. The decline has been attributed to changes in water quality, such as increased turbidity and eutrophication. Plant survival is linked to maintenance of a positive carbon balance, and because shading and anoxic conditions probably reduce the carbon balance in eelgrass, low energy reserves could result in mortality. The Chincoteague Seagrass Study conducted in Chincoteague Bay, Virginia, provided the opportunity to quantify the non-structural carbohydrate reserves along the rhizomes of eelgrass to determine what effects shading and increased sediment oxygen demand have on the carbohydrate reserves of this species. It was determined that starch is conservative in eelgrass, and that shading has the most detrimental effect on the sugar reserves. Further, the interaction of shading and increased sediment oxygen demand reduced sugar reserves to the lowest levels recorded, and also decreased the amount of relative growth observed for the youngest internode tissue.