IMPLICATIONS OF RAPID SEDIMENT ACCUMULATION IN A SMALL NEW-ENGLAND SALT-MARSH

The sediment accumulation rate within a small Spartina alterniflora marsh in Maine has been determined by measuring the amount of peat accretion on top of human-produced boards protruding from an exposed face of the marsh. Boards are at depths of 50-140 cm, suggesting sediment accumulation rates of 6.2-7.0 mm/year. Based on these data and a review of other relevant studies, aggradation in small marshes such as Shipyard Cove should be able to keep pace marginally with the anticipated sea-level rise due to ''greenhouse'' warming, given sufficient sediment supply. Local 19th century land clearance and subsequent erosion, activities that are greatly reduced today, probably supplied the bulk of the inorganic marsh sediment.