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The timing of the initiation of cordgrass migration is coincident with an acceleration in the rate of sea-level rise recorded by the New York tide gauge.
These results suggest that increased flooding associated with accelerating rates of sea-level rise has stressed high-marsh communities and promoted landward migration of cordgrass.
During this time period none of the monitoring quadrats were disturbed by floating wrack, which can lead to rapid plant species shifts (9).
At both sites, the cordgrass/marsh hay border dramatically migrated shoreward during this short period (Fig. Cordgrass cover in these border plots increased more than 5-fold at both sites, whereas marsh hay cover decreased by 16% at Rumstick Cove and 40% at Nag Creek.
Monitoring the boundary between modern cordgrass and the high-marsh community in two representative marshes in Narragansett Bay (Rumstick Cove in Barrington, Rhode Island, and Nag Creek on Prudence Island, Rhode Island; Fig.
1) from 1995 to 1999 revealed increasing dominance of cordgrass at the expense of marsh hay (Fig. At each site we established sixteen 1-m monitoring quadrats on the cordgrass/marsh hay (low marsh/high marsh) border in September 1995.
Existing salt marshes in New England developed during the last 4,000 years and have generally kept pace with moderate rates of SLR of about 1 mm/year (12).
Wetland loss has been documented in areas of the Mississippi River Delta (6) and Chesapeake Bay (7), where rates of local SLR exceed marsh accretion.
In New England salt marshes, cordgrass () dominates higher marsh elevations (8).
igneous and metamorphic rocks with zircon, baddeleyite, perovskite, monazite, titanite, rutile, xenotime, pitchblende, thorite, and thorianite; whole rock carbonates; single-mineral grains from sediments Edwin A.
Olson - Emeritus Professor of Geology, Whitworth College, Spokane, Washington.