Abstract
Great Sippewissett Marsh in Falmouth, MA is the site of a 50-year nutrient-enrichment experiment. Experimental plots were established and fertilized with four different nutrient regimes (low, high, extra high, and no fertilization), in order to evaluate the marsh response. Asa follow-up to this enrichment study, the present study was conducted to measure the amount of belowground carbon and organic matter within the experimental plots at the conclusion of the enrichment period. The goal of this study is to assess whether fertilization of the marsh facilitated increased carbon and/or organic matter accumulation in the sediments and to identify any potential relationship between the amount of fertilizer applied and the amount of carbon or organic matter stored in the sediments. Elevating the marsh surface platform is vital to maintaining the functions of the marsh as sea level rises. In a sediment-starved system such as Great Sippewissett, belowground accumulation of organic matter plays a dominant role in elevating the marsh surface platform. However, the results of this study show that nutrient loading does not facilitate more carbon or organic matter accumulation through production and storage within the marsh sediments and, thus, nutrient loading is unlikely to promote elevation of the marsh surface via belowground accumulation of organic matter.