Rapid shoreward encroachment of salt marsh cordgrass in response to accelerated sea-level rise.

摘要: The distribution of New England salt marsh communities is intrinsically linked to the magnitude, frequency, and duration tidal inundation. Cordgrass ( Spartina alterniflora ) exclusively inhabits frequently flooded lower elevations, whereas a mosaic hay patens ), spike grass Distichlis spicata black rush Juncus gerardi ) typically dominate higher elevations. Monitoring plant zonal boundaries in two marshes revealed that low-marsh cordgrass rapidly moved landward at expense of higher-marsh species between 1995 1998. Plant macrofossils from sediment cores across modern plant community provided 2,500-year record composition documented the migration into high marsh. Isotopic dating revealed that initiation occurred late 19th century continued through 20th century. timing is coincident with an acceleration rate sea-level rise recorded by New York tide gauge. These results suggest increased flooding associated accelerating rates has stressed high-marsh promoted cordgrass. If current continue or increase slightly over next century, will be dominated cordgrass. If climate warming causes increase significantly these cordgrass-dominated marshes likely drown, resulting extensive losses coastal wetlands.