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Meagan Eagle Gonneea

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The accretion history of fringing salt marshes located on the south shore of Cape Cod is reconstructed from sediment cores collected in low and high marsh vegetation zones. These marshes are micro-tidal, with a mean tidal range of 0.442 m. Their location within protected embayments and the absence of large rivers results in minimal sediment supply and a dominance of organic matter contributions to sediment peat. Age models based on 210-lead and 137-cesium are constructed to evaluate how vertical accretion and carbon burial rates have changed over the past century. The continuous rate of supply age model was used to age date 11 cores (10 low marsh and 1 high marsh) across four salt marshes. Both vertical accretion...
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Tidal marsh biomass field plot and remote sensing datasets for six regions in the conterminous United States (ver. 2.0, June 2020)
Remote sensing based maps of tidal marshes, both of their extents and carbon stocks, have the potential to play a key role in conducting greenhouse gas inventories and implementing climate mitigation policies. Our objective was to generate a single remote sensing model of tidal marsh aboveground biomass and carbon that represents nationally diverse tidal marshes within the conterminous United States (CONUS). To meet this objective we developed the first national-scale dataset of aboveground tidal marsh biomass, species composition, and aboveground plant carbon content (%C) from six CONUS regions: Cape Cod, MA, Chesapeake Bay, MD, Everglades, FL, Mississippi Delta, LA, San Francisco Bay, CA, and Puget Sound, WA....
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Salt marshes are environmental ecosystems that contribute to coastal landscape resiliency to storms and rising sea level. Ninety percent of mid-Atlantic and New England salt marshes have been impacted by parallel grid ditching that began in the 1920s–40s to control mosquito populations and to provide employment opportunities during the Great Depression (James-Pirri and others, 2009; Kennish, 2001). Continued alteration of salt marsh hydrology has had unintended consequences for salt marsh sustainability and ecosystem services. Great Barnstable Marsh (Barnstable, Cape Cod, Massachusetts) has areas of salt marsh that were ditched as well as natural areas. The U.S. Geological Survey (USGS) measured parameters for groundwater...
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Continuous monitoring data reported are a portion of data from a larger study investigating changes in soil properties, carbon accumulation, and greenhouse gas fluxes in four recently restored salt marsh sites and nearby natural salt marshes. For several decades, local towns, conservation groups, and government organizations have worked to identify, replace, repair, and enlarge culverts to restore tidal flow upstream from historical tidal restrictions in an effort to restore salt marsh ecosystems on Cape Cod, Massachusetts. Undersized or failed culverts restrict tidal exchange between the marsh and the bays and estuaries, which leads to alterations in plant community composition and in fundamental processes controlling...
Tags: Barnstable County (606927), Bass Creek (615672), CTD measurement, Cape Cod (606914), Cape Cod Museum of Natural History (604249), All tags...
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The Herring River estuary (Wellfleet, Cape Cod, Massachusetts) has been tidally restricted for over a century by a dike constructed near the mouth of the river. Behind the dike, the tidal restriction has caused the conversion of salt marsh wetlands to various other ecosystems including impounded freshwater marshes, flooded shrub land, drained forested upland, and wetlands dominated by Phragmites australis. This estuary is now managed by the National Park Service, which has plans to replace the dike and restore tidal flow to the estuary. To assist National Park Service land managers with restoration planning, study collaborators have been investigating differences in soil properties, carbon accumulation, and greenhouse...
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