Suspended Solids Flux Between Salt Marsh and Adjacent Bay: A Longterm Continuous Measurement

The beneficial roles of coastal salt marshes have been well identified as a storm surge protector, a nursery for young fish and a natural filter for pollutants. However, the vectors of nutrients and suspended solids exchanges between the salt marsh and the adjacent bay are not completely known. In this study, suspended solids flux between a salt marsh at Tuckerton, New Jersey, U.S.A. and Great Bay was continuously measured for an extended period of time by an improved monitoring methodology. A field infrared nephelometric turbidimeter was deployed to measure turbidity continuously at the mouth of the tidal creek, and the measured turbidity data were used to derive suspended solids concentrations. Current velocity and water surface elevation were measured concurrently at the same location. During the monitoring period from March to October 1996, suspended solids were found to be imported into the salt marsh from the adjacent bay. The small net import appeared to be inadequate for wetlands areal viability when compared to the relative sea-level rise rates. Results of this study suggested that a minimum of five water sample sets were needed to establish a reasonably good overall TSS-turbidity regression relationship in terms of flux quantification.