Paper No. 24
Presentation Time: 2:45 PM
CHEMICAL AND PHYSICAL CHARACTERIZATION OF A KETTLE LAKE IN UPSTATE NEW YORK
O'CONNOR, Keith, Department of Geology and Environmental Sciences, Hartwick College, One Hartwick Drive, Oneonta, NY 13820 and BALOGH-BRUNSTAD, Zsuzsanna, Department of Geology and Environmental Sciences, Hartwick College, 1 Hartwick Drive, Oneonta, NY 13820, oconnork2@hartwick.edu
Mud Lake is a rain fed kettle lake bog at approximately 1800 ft in elevation. The bedrock is primarily sandstone, siltstone, and shale in the area surrounding the lake. The purpose of the study was to determine the chemical and physical characteristics of this previously unstudied kettle lake in the Robert V. Riddell State Park of Upstate New York. Depth and temperature profiles of the lake were constructed at several cross-sections of the lake and water samples were collected at five locations and three depths along a north- south transect of the lake. Field parameters such as dissolved oxygen, pH, temperature and electrical conductivity were recorded on-site. Turbidity and dissolved silica concentrations of the water samples were measured immediately after collection, and then the water samples were filtered. The samples were preserved by freezing or by lowering the pH below 2 with nitric acid. Concentrations of cations and anions were analyzed with atomic absorption spectroscopy and ion chromatography, respectively.
Mud Lake is shallow, only 3.5 m deep, with acidic pH ranging from 4.30 to 5.13 and electrical conductivity is 18 to 23 uS/cm, which is consistent with the low buffering capacity of the sand- and siltstone bedrocks. The average surface water temperature of the lake is 28 oC during summer months, but the temperature drops to 8.4 oC at the deepest sections of the lake. Dissolved oxygen concentration is low, 4.65 mg/L at the surface, less than 0.5 mg/L by 1.0 m and decreases to zero at the bottom of the lake. Generally, the water is nutrient poor, low in base cations and dissolved metals and high in organic acids that tint the water to a light to medium brown in color. The highest nutrient concentrations are found at the deepest and coldest point of the lake with 1.28 mg/L total nitrogen and 28 ug/L total phosphorus. Further study will investigate seasonal variations of lake chemistry and water budget of this kettle lake.