ONEIDA LAKE, A HIGHLY PERTURBED LAKE SYSTEM IN CENTRAL NEW YORK

Oneida Lake is the largest inland lake in New York outside of Lake Ontario, within which its drainage basin lies. The system is shallow and has a rich natural history of evolving out of the Late Glacial Lake Iroquois basin. Our work has focused upon the changes (both natural and human induced) near the eastern shore of the lake. For over ten years we have been examining the development of shoreline progradation (over 2.5 km of beach ridge accretion in 10 ka), alluvial plain and channel migration of Fish Creek (a 9 ka history of lateral accretion and sand transport to the lake), wave dominated delta formation (at the mouth of Oneida Creek), and most recently the Late Holocene paleoenvironmental record preserved in sediment cores from the eastern basin. These results demonstrate profound changes in sediment dynamics that are linked to human alteration of: the base level of Fish Creek (which nearly 100 years ago was established at the confluence with the New York State Barge Canal), artificial lowering of lake levels (induced by the canal authority during the winter season), exacerbated erosion of the modern beach and eolian dune system, and enhanced particulate (silt and clay fraction) loading to the lake via Oneida Creek. These events can be recognized in the sediment core stratigraphy as a pronounced increase in sand deposition in the deeper basins of the lake, commencing around 1960. While Oneida Lake remains a naturally eutrophic system the pronounced changes in the physical system are likely to have caused changes in the lakes ecosystem as well. Meanwhile the natural history of shoreline progradation and wide beach accretion has been halted in the last 50 years by a combination of the factors listed above.