Hi all…for several decades now it has been known that phosphorus reduction is good way to control microcystis blooms (the cyanobacteria that produce the regulated microcystin-LR toxin). However, a recent article reports that “an excess of another nutrient, nitrogen, shifts the balance in favor of Microcystis rather than other HAB-forming cyanobacteria, diatoms, or green algae.”
This article is open access so you should be able to download it in its entirety.
Bill
Microcystis Rising: Why Phosphorus Reduction Isn’t Enough to Stop CyanoHABs
S. Levy
Environ Health Perspect; DOI:10.1289/ehp.125-A34 Vol 125, issue 2 2017
https://ehp.niehs.nih.gov/125-A34/
https://ehp.niehs.nih.gov/wp-content/uploads/125/2/ehp.125-A34.alt.pdf
Abstract
“Traditional approaches to managing HABs have focused on controlling phosphorus levels in water. However, new insights into Microcystis ecology challenge long-standing ideas about how best to control these particular blooms. Human-generated phosphorus loads do fuel HABs in Lake Erie and elsewhere, but researchers now understand that an excess of another nutrient, nitrogen, shifts the balance in favor of Microcystis rather than other HAB-forming cyanobacteria, diatoms, or green algae.
“Microcystis relies on nitrogen from the watershed,” says Hans Paerl, a microbial ecologist at the University of North Carolina at Chapel Hill. “Many lakes that have Microcystis blooms are receiving increasing loads of nitrogen from synthetic fertilizers, urban runoff, and atmospheric pollution.Nitrogen is the new part of the story.”
