Cyanobacteria Growth in Nitrogen- & Phosphorus-Spiked Water from a Hypereutrophic Reservoir in Kentucky, USA
Author ORCID Identifier
Jason W. Marion https://orcid.org/0000-0001-5177-889X
Department
Environmental Health Science
Document Type
Article
Publication Date
2-23-2021
Abstract
Cyanobacteria may adversely impact aquatic ecosystems through oxygen depletion and cyanotoxin production. These cyanotoxins can also harm human health and livestock. In recent years, cyanobacterial blooms have been observed in several drinking water reservoirs in Kentucky, United States. In Kentucky, the paradigm is that phosphorous is the limiting nutrient for cyanobacteria growth. To explore this paradigm, an indoor microcosm study was conducted using hypereutrophic Guist Creek Lake water. Samples were collected and spiked with various combinations of locally used agricultural grade fertilizers, including ammonium nitrate, urea, and triple phosphate (calcium dihydrogen phosphate). Samples were incubated indoors for the photoperiod-specific to the time of the year. Cyanobacteria density, measured by phycocyanin, did not demonstrate increased growth with the addition of phosphate fertilizer alone. Cyanobacteria growth was enhanced in these conditions by the combined addition of ammonium nitrate, urea, and phosphorus fertilizer. Growth also occurred when using either ammonium nitrate or urea fertilizer with no additional phosphorus input, suggesting that phosphorus was not limiting the cyanobacteria at the time of sample collection. The addition of both nitrogen fertilizers (ammonium nitrate and urea) at the concentrations used in this study, in the absence of phosphorus, was deleterious to both the Chlorophyta and cyanobacteria. The results suggest further studies using more robust experimental designs are needed to explore lake-specific dual nutrient management strategies for preventing cyanobacterial blooms in this phosphorus-rich hypereutrophic lake and possibly other hypereutrophic lakes.
Recommended Citation
Hughes, S.E. and Marion, J.W. (2021) Cyanobacteria Growth in Nitrogen- & Phosphorus-Spiked Water from a Hypereutrophic Reservoir in Kentucky, USA. Journal of Environmental Protection, 12, 75-89. https://doi.org/10.4236/jep.2021.122006
Journal Title
Journal of Environmental Protection