ASSESSMENT OF BLUE CARBON STOCK IN DELAWARE BAY SALT MARSH

Coastal salt marshes have been recognized as reservoirs for blue carbon sequestration and storage. Despite their environmental services, coastal carbon ecosystems are experiencing dramatic losses. It was estimated that 35% of tidal salt marshes have been lost worldwide (Murray et al, 2011). If this trend continues at a current rate, another 30-40% of tidal marshes could be lost in the next 100 years (Pendleton et al, 2012). Estimates of global blue carbon stock have a high degree of uncertainty; variations in carbon stock and rates of salt marsh losses are poorly documented.

We estimated current total carbon stock of the Fortescue (New Jersey) salt marsh. We compiled historical shoreline change along a 20 km stretch of the Delaware Bay coast for the past 85 years. We documented that the rate of shoreline erosion varies between 0.04 and ~ 8.0 m/year depending on geomorphologic setting.

The stratigraphy of the Fortescue salt marsh documents several episodes of salt marsh erosion related to major storms. We estimated a volume of carbon repository sediments that were lost due to storms during the last century.

We present an estimate of carbon loss due to rising sea level and storm erosion. Our results contribute to the assessment of salt marsh carbon storage and provide a better understanding of the possible extent of carbon release when carbon reservoirs are impacted by erosional events.