MULTI-PROXY RECONSTRUCTION OF A FLOODPLAIN WETLAND IN EASTERN NEW YORK STATE, WITH EMPHASIS ON THE HISTORICAL PERIOD

Pre-settlement mid-Atlantic floodplains were likely characterized by shallow anabranching channels intermixed with scrub-shrub wetlands rather than today’s deeply incised, meandering, single channels. While examining a 1-m peat core from a toeslope floodplain wetland in Columbia County, eastern New York, it was discovered that the Kinderhook Creek likely fit this description. Although the study was designed to investigate colonial-era agriculture—and pollen, phytoliths, and microscopic charcoal were only analyzed above 60cm—plant macrofossil and macroscopic charcoal analyses were conducted on the full core. An AMS date of seeds at 87cm depth indicated that the site transitioned from an open wetland to an Alnus incana ssp. rugosa (green or speckled alder) thicket ca. 6316-6399 cal BP (5580±30 BP). Additional chronostratigraphic markers were identified by comparing historical texts to proxy records, including the novel use of a handheld XRF scanning device that enabled rapid identification of ca. 1800 AD by detecting an increase in lead above 39cm. The presence of high numbers of spores from the coprophilous fungi Sordaria at 44-46cm indicated that colonists used the wetland as a pasture just prior to its transition from dry alder thicket to open, moist sedge meadow. Phytoliths distinguished between grass subfamilies and provided an excellent record of the introduction of invasive Phragmites australis in the mid-twentieth century. Poor preservation of organic fossils in the woody peat prevented detailed macrofossil and pollen analyses below 40cm. Inorganic phytoliths, however, show promise for reconstructing vegetation in highly degraded substrates; non-pollen palynomorphs have also proven useful in such environments. Together with what is known about natural cycles in European alder thickets, this research suggests that the earliest European settlers along the Kinderhook Creek encountered a mosaic of arable land and wet meadows able to support their mixed-husbandry livelihoods.