"Every person is the right person to act. Every moment is the right moment to begin" -Jonathan Schell
Benthic Diatom Community Dynamics in Seneca-Keuka Lake Watershed: Microbial Indicators of Freshwater Ecosystem Health
Rochester Academy of Sciences Undergraduate Student Research Grant Award
Northeast Algal Society Ron Hoham Undergraduate Student Research Grant Award
Completion date: est. December 2025
This study aims to investigate the relationship between benthic diatom community composition and environmental parameters within the Seneca-Keuka Lake watershed, focusing on the impacts of nutrient availability and site-specific conditions on algal diversity and primary productivity. Benthic diatom samples will be collected from varying locations in and surrounding Keuka Lake to represent both oligotrophic and mesotrophic conditions. Chlorophyll-a concentrations will be measured as a means of evaluating primary productivity, using an ethanol extraction method followed by spectrophotometric analysis at 665 nm and 750 nm before and after acidification to account for phaeopigment interference. Diatom samples will be preserved, mounted and identified microscopically to characterize species composition and abundance at each site.
The objectives of this research are to 1) assess spatial variation on diatom community structure across varying environmental conditions, 2) evaluate the relationship between nutrient availability and chlorophyll-a concentrations, and 3) explore the potential of benthic diatoms as indicators of freshwater ecosystem health.
Cost Effective Methods for Analyzing Nitrate and Phosphate in Lake Samples
Keuka College is a primarily undergraduate institution located on the shore of Keuka Lake. With limited research funding, the College’s Center for Aquatic Research is seeking cost-effective nutrient analysis methods to determine nutrient run-off hotspots around the lake. Over the past few decades, Keuka Lake, in the Finger Lakes region of Upstate New York, has changed from an oligotrophic lake to a mesoligotrophic lake. With Keuka Lake becoming mesoligotrophic, more cyanobacterial harmful algal blooms have been identified in recent years. This can lead to ecological imbalances and water quality deterioration affecting Keuka Lake’s ecosystem dynamics, lake eutrophication, and economic impacts on local towns. Here, potential cost-effective UV-Spectrophotometry methods were utilized for determining total nitrogen by second-derivative and soluble reactive phosphorus via molybdate blue. Future research will aim to validate the reliability of these methods and expand sampling potential hotspot sites across Keuka Lake to determine where excessive nutrient levels originate.
In June 2023, 11 rivers from the Bering Sea to the Arctic Ocean were sampled within a two-week period. 12 samples were collected from each river resulting in 132 samples. These samples were processed to determine the relationships between different aspects of aquatic biofilm across a latitudinal gradient. The aquatic biofilm consisted of diatom sample. Diatom samples from each river were cleaned using hydrochloric acid then mounted on Naphrax medium for microscopic analysis. Chlorophyll-a (chl-a) analysis of samples was also completed using filtered river water through a 0.7 mm GF/F fiberglass filter (Whatman), applying vacuum until the sample was dry. Ethanol was then added to samples and refrigerated overnight to incubate. After centrifugation, chl-a was analyzed using UV-Spectrophotometry at 665 nm and 750 nm both before and after acidification using hydrochloric acid. This research will be used to determine what environmental parameters drive biofilm composition which will in turn lead to a better understanding of potential future environmental changes in the region associated with climate change.