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"Tidal Marshes of Barnegat Bay - Nutrient History and Ecosystem Services"

Wetlands support physical and ecological functions that result in valuable services to local water bodies and society, including removal of reactive nitrogen from surface water and groundwater. Nutrient enrichment by surface runoff is the main reason for hypoxia and eutrophication in coastal waters. Among the transported nutrients, nitrogen and its different forms are one of the major culprits of eutrophication. Nutrients can enter coastal waters and estuaries from river runoff, direct discharge, atmospheric deposition, and ocean exchange and can be exported or removed through burial (i.e., both in marshes and subtidal), ocean exchange, and importantly for nitrogen: denitrification a microbial mediated process (i.e., NOx  N2). In the present series of studies nitrogen removal as an important ecosystem services was studied by taking sediment cores from tidal wetlands in Barnegat Bay. We hypothesized that tidal marshes in Barnegat Bay denitrifies or bury a significant amount of nitrogen. Deep sediment cores taken in 2010 show that burial accounts for a substantial removal of N relative to loadings. Denitrification rates in the vegetated marshes, natural, and managed ponds were similar and depend on season. Denitrification rates in the marsh sites were higher in July and lower in October. Denitrification and burial rates relative to loadings from tributaries to Barnegat Bay suggest that the remaining wetland area is vital to the health of the bay and impacts from sea level rise could alter the ecosystem in the future.