Researchers from Laurentian University are delving into the history of northeastern Ontario lakes to assist communities in managing blue-green algae blooms. Mackenzie Hobbs, a Masters student, has been collecting sediment samples to analyze the impact of industrialization on blue-green algae levels in the waters. Hobbs emphasized the importance of understanding historical phosphorus levels in lakes to gauge the extent of human-induced changes that have spurred the growth of cyanobacteria, leading to harmful algae blooms.
High nutrient levels, particularly phosphorus, create favorable conditions for cyanobacteria proliferation and the subsequent formation of blue-green algae blooms. These blooms can release toxins harmful to both humans and animals, sometimes prompting beach closures. Hobbs highlighted the significance of studying lake sediment, which provides insights spanning over two centuries, predating the influx of nutrients from industrial activities into water bodies.
Chironomids, the larval form of flies residing in sediment, serve as valuable indicators of oxygen levels in lakes. By analyzing these organisms, researchers can infer the historical dissolved oxygen content, aiding in understanding ecosystem changes over time. Furthermore, Hobbs is focusing on diatoms, a type of microalgae thriving in nutrient-rich environments, to assess past phosphorus concentrations in the lakes accurately.
Professor Liz Favot, overseeing Hobbs’s research at Laurentian University, emphasized the potential of identifying lakes with elevated phosphorus levels compared to pre-industrialization periods, signaling areas for targeted intervention by municipalities. Despite low nutrient levels in some lakes, blue-green algae blooms persist due to climate change, with cyanobacteria adapting to warmer water conditions, making management challenging.
The study’s implications extend to Espanola, where Apsey Lake serves as the town’s primary drinking water source. Joseph Burke, Espanola’s chief administrative officer, acknowledged the research’s relevance in shaping land use policies near the lake. Burke noted an uptick in blue-green algae blooms at Apsey Lake since 2015, prompting considerations for new policies to safeguard the lake’s health through effective land use planning measures.