J.A. Peck J.R. Allen J.W. King P.G. Appleby C. T. Roman 1997 <p><span>Sediment accumulation rates were determined at several sites throughout Nauset Marsh (Massachusetts, U.S.A.), a back-barrier lagoonal system, using feldspar marker horizons to evaluate short-term rates (1 to 2 year scales) and radiometric techniques to estimate rates over longer time scales (</span>¹³⁷<span>Cs,</span>²¹⁰<span>Pb,</span>¹⁴<span>C). The barrier spit fronting the</span><i>Spartina</i><span>-dominated study site has a complex geomorphic history of inlet migration and overwash events. This study evaluates sediment accumulation rates in relation to inlet migration, storm events and sea-level rise. The marker horizon technique displayed strong temporal and spatial variability in response to storm events and proximity to the inlet. Sediment accumulation rates of up to 24</span><span>&nbsp;</span><span>mm year</span>⁻¹<span>were recorded in the immediate vicinity of the inlet during a period that included several major coastal storms, while feldspar sites remote from the inlet had substantially lower rates (trace accumulation to 2·2</span><span>&nbsp;</span><span>mm year</span>⁻¹<span>). During storm-free periods, accumulation rates did not exceed 6·7</span><span>&nbsp;</span><span>mm year</span>⁻¹<span>, but remained quite variable among sites. Based on</span>¹³⁷<span>Cs (3·8 to 4·5</span><span>&nbsp;</span><span>mm year</span>⁻¹<span>) and</span>²¹⁰<span>Pb (2·6 to 4·2</span><span>&nbsp;</span><span>mm year</span>⁻¹<span>) radiometric techniques, integrating sediment accumulation over decadal time scales, the marsh appeared to be keeping pace with the relative rate of sea-level rise from 1921 to 1993 of 2·4</span><span>&nbsp;</span><span>mm year</span>⁻¹<span>. At one site, the</span>²¹⁰<span>Pb-based sedimentation rate and rate of relative sea-level rise were nearly similar and peat rhizome analysis revealed that</span><i>Distichlis spicata</i><span>recently replaced this once</span><i>S. patens</i><span>site, suggesting that this portion of Nauset Marsh may be getting wetter, thus representing an initial response to wetland submergence. Horizon markers are useful in evaluating the role of short-term events, such as storms or inlet migration, influencing marsh sedimentation processes. However, sampling methods that integrate marsh sedimentation over decadal time scales are preferable when evaluating a systems response to sea-level rise.</span></p> application/pdf 10.1006/ecss.1997.0236 en Elsevier Accretion of a New England (U.S.A.) salt marsh in response to inlet migration, storms, and sea-level rise article