14,000 years of sediment, vegetation, and water-level changes at the Makepeace Cedar Swamp, southeastern Massachusetts

Data from a transect of four cores collected in the Makepeace Cedar Swamp, near Carver, Massachusetts, record past changes in deposition, vegetation, and water level. Time series of palynological data provide a 14,000-yr reco rd of regional and local vegetation development, a means for biostratigraph ic correlation and dating, and information about changes in water level. Di fferences in records among cores in the basin show that water level decreas ed at least 1.5 m between similar to 10,800 and 9700 cal yr B,P., after whi ch sediment accumulation was slow and intermittent across the basin for abo ut 1700 yr. Between 8000 and 5600 cal yr B.P,, water level rose similar to 2.0 m, after which slow peat accumulation indicates a low stand about the t ime of the hemlock decline at 5300 +/- 200 cal yr B.P, Dry conditions may h ave continued after this time, but by 3200 cal yr B.P., the onset of peat a ccumulation in shallow cores indicates that water level had risen to close to its highest postglacial level, where it is today, Feat has accumulated a cross the whole basin since 3200 cal yr B,P, Data from Makepeace and the Pe quot Cedar Swamp, near Ledyard, Connecticut, indicate an early Holocene dry interval in southern New England that began 11,500 yr ago near the end of the Younger Dryas interval. The dry conditions prevailed between 10,800 and 8000 cal yr B,P, and coincide with the arrival and later rise to dominance of white pine trees (Pinus strobus) both regionally and near the basins. O ur results indicate a climatic cause for the "pine period" in New England. (C) 2000 University of Washington.