GEOCHEMICAL AND MICROFOSSIL RECORD OF MASS HEMLOCK DIE-OFFS IN THE SEDIMENT OF BARTON'S COVE, WESTERN MASSACHUSETTS
To examine the history of nutrient runoff, an 8-meter core was recovered from Barton’s Cove, a former plunge pool that lies 117 kilometers north of the mouth of the Connecticut River. The low-energy environment of the pool makes it an ideal sink for fine-grained sediments and the organic material that runs off from the surrounding forest. Radiocarbon dates indicate that the core contains sediments spanning the last 6194 years BP. This range includes the other major Holocene hemlock declines and massive die-offs. Organic matter content is high in these sections of the core, ranging from 40% to ~75% TOC, and the carbon isotopic values of the organic matter indicates a mainly terrestrial origin (-33.5‰ to -28‰). We will attempt to quantify the changes in nutrient loading to Barton’s Cove during the hemlock die-off by both direct measurement of total phosphorous and by Diatom analysis. The findings of this project may contribute to predicting ongoing changes due to hemlock declines and rapid soil organic mobilization by the Woolly Adelgid and earthworms, respectively.