Decreased water transparency of nearshore Laurentian Great Lakes habitats is driven by increased dissolved organic carbon.

Canadian Journal of Fisheries and Aquatic Sciences
By: , and 

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Abstract

Little is understood of lake browning (due to increased dissolved organic carbon; DOC) in large lakes such as the Laurentian Great Lakes. Lake browning can alter whole lake ecosystems, including decreasing exposure to damaging ultraviolet radiation (UV-B) which is strongly and selectively attenuated by DOC more so than photosynthetically active radiation (PAR). We compared the changes in UV-B and PAR transparency to DOC data collected during the ice-free seasons from 62 nearshore sites in four of the five Great Lakes from 2002 to 2022 using linear mixed effects regression models based on backwards selected Bayesian information criteria. Regionally, DOC significantly increased from 2002 to 2022 by 0.5% per year on average. DOC strongly and inversely explained the variability of UV-B and PAR transparencies, as did seasons and offshore influence on these habitats. We provide regional evidence of lake browning within the nearshore habitats of the Great Lakes as a strong contrast to the well-documented increased offshore water transparency associated with the spread of invasive dreissenid mussels.

Suggested Citation

Berry, N., Bunnell, D.B., Fisher, T., Overholt, E., Mette, E., Howell, T., Williamson, C.E., 2026, Decreased water transparency of nearshore Laurentian Great Lakes habitats is driven by increased dissolved organic carbon.: Canadian Journal of Fisheries and Aquatic Sciences, v. 83, p. 1-9, https://doi.org/10.1139/cjfas-2024-0407.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Decreased water transparency of nearshore Laurentian Great Lakes habitats is driven by increased dissolved organic carbon.
Series title Canadian Journal of Fisheries and Aquatic Sciences
DOI 10.1139/cjfas-2024-0407
Volume 83
Year Published 2026
Language English
Publisher Canadian Science Publishing
Contributing office(s) Great Lakes Science Center
Description 9 p.
First page 1
Last page 9
Country Canada, United States
Other Geospatial Great Lakes
Additional publication details