Inorganic chemical profiles of the sediment cores from six northeastern Ohio reservoirs

Abstract

The relationship between lake trophic state and lake sediments has been recognized for over fifty years. Sediment cores were collected from six Northeastern Ohio Reservoirs (the Ohio Works Service Reservoirs) Pine, Evans, Hamilton, McKelvey, Liberty, and Girard. Cores were sliced into centimeter sections and each section was analyzed for water content, organic matter content, total carbon, nitrogen, sulfur, aluminum, iron, manganese, calcium and magnesium. Mean concentrations of the elements linear regression analysis of each parameter with depth and ratio analysis were used to evaluate the trophic history of the six reservoirs. No significant increases in trophic state were found in Lake Pine, however, the high concentrations of organic matter, carbon, nitrogen and the significant positive correlation between Fe:Mn and depth, are indicative of high trophic state of Lake Pine. Lake Evans has significant increases in carbon, nitrogen, organic matter and calcium towards recent sediments, and a significant positive correlation between Fe:Mn ratio and sediment depth indicating eutrophication. The distribution of carbon, nitrogen, sulfur, Fe:S ratios, and calcium in Lake Hamilton sediments indicates the lake has experienced a peak in productivity early in its development, and a second increase in productivity in recent times. Lake McKelvey has significant increases towards recent sediments in carbon, nitrogen, sulfur and calcium content, and significant positive correlations between Fe:S and depth and Fe:Mn and depth indicating increased productivity. Lake Liberty shows signs of eutrophication by the significant concentrations of carbon, nitrogen, organic matter and its high Fe:Mn ratio. Lake Girard has significant increases in carbon, nitrogen, organic matter, sulfur and calcium and significant positive correlations between Fe:S and depth, and Fe:Mn and depth indicating increases productivity.