Skaneateles Lake in Upstate New York is one of the cleanest, clearest freshwater lakes in the country, the source of drinking water for the City of 黑料不打烊 and a hub for recreation. Since 2017, however, harmful algal blooms (HABs) have been observed in the lake each summer, potentially threatening the area鈥檚 chief water supply.
Christopher Scholz
HABs occur when colonies of cyanobacteria grow out of control. 鈥淭hey can be very toxic,鈥� says Christopher Scholz, professor of Earth and environmental sciences in the College of Arts and Sciences. 鈥淚f there’s a HAB in a freshwater lake, you certainly don’t want to be drinking that water and you don’t want to be bathing in it or have your dog swimming in it.鈥�
Scholz鈥檚 research focuses on paleolimnology鈥攔econstructing the past environments of inland waters through their geologic record鈥攁nd he has studied climate change using sedimentary analysis of lake basins ranging from Lakes Malawi and Taganyika in the East African Rift Valley to Lake Baikal in Siberia to freshwater lakes in Upstate New York. He鈥檚 now using similar techniques to study environmental changes in Skaneateles Lake and nearby Oneida Lake over the last 350 years, a starting point for research that may eventually provide a historical record of environmental conditions leading to HABs on the lakes.
Scholz has received $34,000 from the , a program based out of Cornell University, to collect sediment cores from the two lakes to determine spatial patterns of sedimentation and take measurements of nutrients including phosphorus, carbon and nitrogen to see how those have varied over time.
Researchers from the Departments of Earth and Environmental Sciences and Civil and Environmental Engineering collect sediment cores from Skaneateles Lake in October 2021.
鈥淭he layers of sediment at the bottom of a lake basin are essentially a tape recorder of environmental change over time,鈥� Scholz says. 鈥淲ithin this relatively small project, we’re trying to get a sense of how the loading of nutrients into the lakes have changed just over the last 300-350 years, from precolonial times to the present.鈥�
Skaneateles Lake is an oligotrophic lake, meaning it contains low nutrient content leading to clear water due to limited algae growth. Scholz says the recent HABs are unusual. 鈥淲e know essentially nothing about past, ancient occurrences of HABs in the lake,鈥� he says.
Oneida Lake, by contrast, is a eutrophic lake. 鈥淧arts of it turn green every summer on account of high biological productivity, and there鈥檚 a longer history of HABs occurring,鈥� he says.
Comparing sediment cores from the two lakes may provide answers to environmental conditions that lead to HABs.
Scholz is collaborating on the project with 黑料不打烊 colleagues Charles T. Driscoll, University Professor of Environmental Systems and Distinguished Professor of civil and environmental engineering in the College of Engineering and Computer Science, and Melissa Chipman, assistant professor of arctic paleoecology and paleoclimate in the Department of Earth and Environmental Sciences.
Staff technician Jacqueline Corbett and graduate student Laura Streib examine a sediment core from Oneida Lake.
In partnership with the New York State Department of Environmental Conservation, the Skaneateles Lake Association and the Oneida Lake Association, the team is collecting core samples from both lakes to quantitatively measure how the sediment in each lake changed in accumulation and composition over time, as well as to establish patterns of sediment accumulation in different locations in the lakes.
鈥淪ediment doesn’t accumulate evenly all around the bottom of a lake,鈥� Scholz says. 鈥淪o, identifying the key sites to evaluate these kinds of changes is very important and will inform future studies.鈥�
Ultimately, understanding past history of environmental change leading to HABs may help scientists protect water quality in the future. 鈥淲e can鈥檛 take these remarkable natural resources for granted,鈥� Scholz says. 鈥淲e live in a changing world and water conditions are definitely evolving.鈥�
