In recent years, salt marsh drowning has been observed in Long Island Sound.  This drowning is characterized by the loss of elevation relative to the sea level and conversion of vegetated marsh to mudflat. It was the objective of this research to quantify the effect of nutrients and other site factors on decomposition rates in salt marshes of Long Island Sound. Decomposition rates of sediment and macro-organic matter were measured at three marsh sites, each in a different state of ecosystem health; steady-state, or maintaining sediment elevation levels and vegetation, aggrading, and drowning. The steady-state site was amended with nitrogen and phosphorus additions.  Results show insignificant changes in decomposition rates of sediment over a three month time period. Likewise, no significant differences in decomposition rates were found for macro-organic matter at the fertilized plots. However, significant differences were seen between marsh sites, specifically when comparing the drowning marsh, to the healthier marshes. These results indicate that drowning may occur in part due to elevated decomposition rates, but the reasons behind these increased rates remains unclear. Future sampling of the nutrient-amended plots is necessary, as the three month time span for this study was too short a duration to witness the possibly significant effects of nutrients on decomposition rates.