RT Journal Article
T1 Cyanobacteria in winter: Seasonal dynamics of harmful algal blooms and their driving factors in boreal lakes
A1 Grosbois, Guillaume
A1 Anjum Mou, Tasnim
A1 Montoro Girona, Miguel
AB Lake cyanobacteria can overgrow and form blooms, often releasing life-threatening toxins.Harmful algal blooms (HABs) are typically caused by excess nutrients and high temperatures, butrecent observations of cyanobacteria beneath the ice in boreal lakes suggest that the dynamics aremore complex. This study investigates the seasonal dynamics of HABs in boreal lakes and identifiestheir driving factors. We study cyanobacteria assemblages in two boreal lakes in Abitibi-T´emiscamingue (Quebec, Canada): Lake Fortune, noted for its under-ice cyanobacteria, and LakeBeauchamp, which has experienced recurrent summer-only cyanobacterial blooms. From June2021 to July 2022, we identified monthly cyanobacterial communities and estimated water nutrients,organic carbon, temperature, oxygen, and pH. Cyanobacterial communities were dominatedby the genus Planktothrix in Lake Fortune, and this genus was in a bloom state for eachmonth of the year. Cyanobacterial abundance was highest (210 000 cells/mL) in November andlowest (28 000 cells/mL) in March. The abundance of Planktothrix correlated with total nitrogenand phosphorus and dissolved organic carbon concentrations. Planktothrix dominated even underice cover, because of its ability to thrive in low-light and low phosphorus conditions. In LakeBeauchamp, Aphanothece was found throughout the year, highest (27 800 cells/mL) in August andlowest (2100 cells/mL) in March. In Lake Beauchamp, cyanobacterial blooms correlated withtotal dissolved phosphorus, nitrogen and organic carbon concentrations during summer and fall.The dominance of Aphanothece was especially pronounced during the summer and fall. Our studyprovides new knowledge about the seasonal dynamics of cyanobacterial blooms to help guide thefuture management of HABs in boreal lakes.
PB Elsevier
SN 2405-8440
YR 2024
FD 2024-11
LK https://hdl.handle.net/10272/24854
UL https://hdl.handle.net/10272/24854
LA eng
NO Grosbois, G., Anjum Mou, T., & Montoro Girona, M. (2024). Cyanobacteria in winter: Seasonal dynamics of harmful algal blooms and their driving factors in boreal lakes. In Heliyon (Vol. 10, Issue 24, p. e40687). Elsevier BV. https://doi.org/10.1016/j.heliyon.2024.e40687
NO This project was funded by grants from MITACS obtained by GG and MMG. Part of the project was funded with a grant from the Fondation UQAT (FUQAT) obtained by GG and MMG. The part of the project focused on Lake Beauchamp was funded through a grant from the Ville d’Amos obtained by GG. Cyanobacteria sample analyses from Lake Fortune were funded by the Ministère de l’ Environnement, de la Lutte contre les changements climatiques, de la Faune et des Parcs. Part of the equipment was provided by a FCI grant – SmartForest.
DS Repositorio Institucional de la Universidad de Huelva
RD 30 may 2026