Paper No. 343-22
Presentation Time: 2:15 PM

POTENTIAL INFLUENCE OF LAKE MORPHOMETRY ON PALEOPRODUCTIVITY PATTERNS IN LAKES UNDER SIMILAR CLIMATE CHANGE CONDITIONS IN THE ADIRONDACK MOUNTAINS OF NEW YORK


ROBINSON, Sarah1, KANFOUSH, Sharon L.1, and SPADO, Anthony J.2, (1) Department of Geology, Utica College, 1600 Burrstone Road, Utica, NY 13502, snrobins@utica.edu, (2) Science Department, Rome Free Academy, 409 Bell Road, Rome, NY 13440
Kling et al. (2000) reported geographically proximal lakes subjected to similar climate change conditions responded similarly, and thus exhibited synchrony. Kanfoush (2013) reported changes in diatoms in 4th Lake of the Fulton Chain of Lakes in the Adirondacks strongly correlated with changes in northern hemisphere temperature (NH-T), atmospheric CO2, and solar irradiance. Spado (2008), however, found other lakes in the Fulton Chain, which are both proximate and hydrologically connected, did not exhibit synchrony in changes in their physical and chemical sediment characteristics, due to differences in individual lake morphometry. We hypothesize the lakes’ paleoproductivity also responded asynchronously. Old Forge Pond, 2nd Lake, and 3rd Lake of the Fulton Chain were analyzed in this study. Although semi-connected and subjected to similar climate, these lakes have varied morphometry. Cores recovered in 2006 were sampled at 1-cm intervals, 210Pb dated, and ≥400 diatom valves counted in each at 400x magnification via DIC microscopy.

Diatom concentration and accumulation in Old Forge Pond and 3rd Lake did not appear to respond significantly to changes in NH-T, atmospheric CO2, or solar irradiance. However, in 2nd Lake diatom concentration correlates with NH-T and atmospheric CO2 (R = 0.28 and 0.66, respectively) and diatom accumulation with NH-T, CO2, and irradiance (R = 0.58, 0.61, and 0.50, respectively). Strong correlations with these parameters are also observed for 2nd Lake % organics (R = 0.84, 0.91, and 0.56) and organic mass (g) (R = 0.54, 0.67, and 0.30) Thus, it appears biological productivity of these semi-connected lakes does not respond to climate forcing in a similar manner. Alternatively, some lakes may respond more substantially to land use changes. An understanding of potential variability of individual lake response to similar climate and other environmental forcing is useful to local land-use planners and policy-makers as they seek to mitigate impacts.