Visiting Scholar Dr. Diane M. Orihel, in UWinnipeg’s Department of Biology, has published a new paper in the scientific journal Limnology and Oceanography on the causes of harmful algal blooms in Canadian lakes entitled The ‘nutrient pump’: Iron-poor sediments fuel low nitrogen-to-phosphorus ratios and cyanobacterial blooms in polymictic lakes. Her study examined the factors responsible for promoting blooms of cyanobacteria (colloquially called ‘blue green algae’) in a nutrient-rich lake in Alberta and found that low concentrations of iron in sediments and frequent mixing events in the lake, together, lead to blooms of harmful cyanobacteria.
photo of cyanobacteria, colloquially called ‘blue green algae’
Blooms of ‘blue green algae’ are common in many Canadian lakes and reservoirs, especially across the prairies. Such blooms impair water quality, which reduces shoreline property values, increases the cost of water treatment, and diminishes profits from fisheries. Blooms are also a concern for human health because cyanobacteria can produce potent brain and liver toxins.
Orihel’s research is particularly relevant to Lake Winnipeg as well as many shallow lakes in southwestern Manitoba. “This study has two major implications”, explained Orihel. “First, it points to the need for considering iron treatment as a potential management strategy for nutrient-rich lakes with low levels of sedimentary iron. Second, it suggests that we can expect more blooms as climate change proceeds in the future.”
The paper is written by Diane M. Orihel, David W. Schindler, Nathaniel C. Ballard , Mark D. Graham, David W. O’Connell , Lindsey R. Wilson, and Rolf D. Vinebrooke). The abstract is available on-line at http://onlinelibrary.wiley.com/doi/10.1002/lno.10076/abstract.
Limnology and Oceanography publishes research articles, reviews, and comments about all aspects of limnology and oceanography. The journal’s unifying theme is the understanding of aquatic systems. Submissions are judged on their originality and intellectual contribution to the fields of limnology and oceanography. Site-specific studies, laboratory experiments, and modeling exercises will be considered only to the extent they contribute to a broader understanding of aquatic sciences.
