ASSESSING TWO CENTURIES OF ANTHROPOGENIC IMPACTS ON SILVER LAKE, SUMMIT COUNTY, OHIO

The increase in human population and human activities often negatively impacts the quality of our waters. Lake sediment often preserves a record of past anthropogenic activities and can be used to assess the impact of humans on the lake system. This study examines Silver Lake, a groundwater-fed kettle lake located in the township of Silver Lake, Summit County, Ohio. Surface samples and water column profiles were collected to assess present-day conditions. The lake is eutrophic, with a hypoxic hypolimnion during the summer months, and the health of the lake is of concern to the local residents. Silver Lake contains two basins and sediment cores were collected from both basins to assess long-term changes in the lake. Preliminary results indicate that the sediment in both basins display similar trends. Below 156 cm core depth, a brown, organic-rich gyttja is interpreted to represent lake/watershed conditions prior to the arrival of New Englanders in 1804. The decline in sediment organic content and corresponding increase in bulk density at 125 cm likely reflects the impact of land clearance within the watershed following settlement. Between 70 -108 cm, a black mud having an oily odor and low organic content is present. This black mud has pronounced increases in ferrimagnetic content, fly-ash particles, and bulk density, and likely was deposited between 1874 and 1917 when a major amusement park, complete with steamboat rides, occupied the western shore of the lake. When the park closed in 1917 the land was converted into suburban housing and by the mid-late 20^th century the entire watershed was occupied by suburban housing. The brown mud above 70 cm core depth displays decreasing trends in ferrimagnetic content and fly-ash particles reflecting changes in anthropogenic activities during the mid-to-late 20^th century. Study of the lake sediment allows the impacts of humans on the Silver Lake system to be assessed and the present-day conditions to be placed in a long-term context.