A new study could upset some of the conventional wisdom around algae growth and nutrient management in freshwater systems.
Phosphorus limitation “has been regarded as the rule” in freshwater systems when it comes to managing algae, according to the study published in the scholarly journal Hydrobiologia.
But maybe that’s not the best approach.
“The nutrient phosphorus has long been regarded as the key to algal growth in freshwater systems. However our results show that both phosphorus and nitrogen are equally important for growth of algae,” study authors Stefanie Mueller and Simon Mitrovic of Sydney’s University of Technology explained in a statement.
“Under regular conditions sediments play an important role in removing nitrogen from the water, limiting algal growth. Our research shows, however, that under low-oxygen conditions, sediments release considerable amounts of nitrates which can spark significant increases in algal growth,” they continued.
The authors say their study suggests shifts in typical algae management practices. “[The findings mean] water reservoir management needs to take into account the amount of nitrogen the sediments in Grahamstown Dam contribute to water column concentrations when setting limits for concentrations of nitrogen pumped into the lake,” the authors said.
Algae can pose major challenges to the effective operation of drinking water facilities. Toledo, OH, banned water use for over two days last year due to toxic algae contamination, CNN reported.
Cyanotoxins, which are produced by blue-green algae, are on the EPA’s Candidate Contaminant List 3,which enumerates harmful pollutants for potential regulatory action.
For similar stories on preventing algal bloom, visit Water Online’s Nutrient Removal Solutions Center.
Image credit: “Lake Erie Algae, PutInBay OH,” © 2010 AKZOphoto, used under an Attribution-NoDerivs 2.0 Generic license: http://creativecommons.org/licenses/bynd/2.0/