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The sustainability of coastal wetlands largely hinges on their ability to accrue elevation capital at a rate that equals or exceeds relative sea-level rise. A better understanding of these processes is needed to accurately assess the sustainability of these landscapes, and to predict their response to restoration measures such as sediment delivery through river diversions.
Strontium isotope (87Sr/86Sr) profiles in sediment cores collected from two subtidal harbor slips in the lower Hudson River estuary in October 2001 exhibit regular patterns of variability with depth. Using additional evidence from sediment Ca/Sr ratios, 137Cs activity and Al, carbonate (CaCO3), and organic carbon (OCsed) concentration profiles, it can be shown that the observed variability reflects differences in the relative input and trapping of fine-grained sediment from seaward sources vs. landward sources linked to seasonal-scale changes in freshwater flow. During high flow conditions, the geochemical data indicate that most of the fine-grained sediments trapped in the estuary are newly eroded basin materials....
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To parameterize accretion for SLR models, we measured historic rates of mineral and organic matter accumulation at each site by collecting deep soil cores with a Russian peat borer. At each site, we obtained cores in each of three vegetation zones: low, medium, and high marsh. Two replicate cores were sampled from each station for a total of 6 cores per site (except Coos Bay where 7 cores were taken). Coring locations were determined by RTK GPS elevation and tidal inundation data. Transects for core sampling were determined in ArcGIS, using a digitial elevation model and site-specific tidal datums to choose station locations below MHW (low), between MHW and MHHW (mid), and above MHHW (high). Sediment cores were...


    map background search result map search result map USGS Pacific Tidal Marsh Soil Core Surveys, Pacific Northwest US, 2013-14 Soil properties, soil radioisotope activity, and end-of-season belowground biomass across Barataria basin wetlands (2016) Soil properties, soil radioisotope activity, and end-of-season belowground biomass across Barataria basin wetlands (2016) USGS Pacific Tidal Marsh Soil Core Surveys, Pacific Northwest US, 2013-14