SALT MARSH
Nothing is more symbolic of the South Carolina Lowcountry than the great expanse of tidal salt marshes . These ecosystems are as dynamic and diverse as they are beautiful . Twice a day , these habitats are inundated and then drained with salt water due to the ebb and flow of semidiurnal tides . In lower elevations they are dominated by Spartina cordgrass but contain a diversity of other wetland plants in higher elevations . Of the 8,500 acres of land mass that make up Kiawah Island , 3,750 acres are comprised of saltmarshes ( Gramling , 2012 ). This also presents the Island with over 50 miles of marsh frontage , compared to the 10 miles of beach front . In a recent survey of property owners , the marshes were cited as a major driver for moving to Kiawah Island ( AMP Task Force , 2020 ).
While tidal wetlands are beautiful and characteristic of the lowcountry , they also support a variety of benefits that greatly benefit human and wildlife communities ( Millennium Ecosystem Assessment , 2005 ). Coastal wetlands are widely considered one of the most biologically productive ecosystems in the world . Despite wetlands only comprising 4 % of the world ’ s total land cover , one third of the world ’ s population is dependent on the critical ecosystem services they provide ( Millennium Ecosystem Assessment , 2005 ; Barbier , 2013 ). This also applies to coastal communities such as Kiawah Island , where tidal salt marshes protect the land from erosion by reducing wave action , buffering storm surges , as well as providing abundant wildlife , recreational , and aesthetic amenities . It is estimated that the valuation of the ecological benefits provided by tidal wetlands is approximately $ 78,510 per acre per year ( Barbier et al ., 2011 ; Constanza , 2014 ). This suggests the expanse of saltmarshes ( tidal and nontidal ) around Kiawah Island provide approximately $ 294.4 million per year in ecosystem services to property owners .
Though they are one of the most productive ecosystems , coastal wetlands are also one of the most vulnerable to change . Coastal wetlands have been declining globally , with future projections suggesting further decline due to sea-level rise ( Blankespoor et al ., 2014 ; Schuerch et al ., 2018 ). Human population densities in the coastal regions are nearly three times that of inland areas , and are exponentially increasing ( Sandifer et al ., 2004 , Neumann et al ., 2015 ). With this , there is concern for the long-term stability of coastal populations due to future impacts to tidal salt marshes . Sea-level rise , major storm frequency and intensity , stormwater , and coastal development all have the potential to negatively impact the health of salt marshes . This in turn would create negative impacts on coastal communities . Numerous species of birds such as herons , egrets , ospreys feed on the invertebrates and fish
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