Hidden chemical pathway could keep phosphorus from fueling lake algal blooms
Why do some lakes remain plagued by harmful algal blooms even after phosphorus pollution has been reduced? Part of the answer lies beneath the surface. A new Concordia study has uncovered a previously overlooked chemical process that can help trap phosphorus in lake sediments, preventing it from returning to the water, where it can fuel excessive plant and algal growth.
A newly discovered pathway in lake sediments could help prevent phosphorus from fueling harmful algal blooms, according to a study conducted by researchers at Concordia University. The study, published in Scientific Reports, identifies mackinawite—a mineral formed in oxygen-depleted sediments—as a previously overlooked chemical process that can trap phosphorus and prevent it from returning to the water.
Mackinawite, an iron sulfide mineral, becomes unstable when oxygen levels decline, allowing conventional phosphorus-binding minerals to break down and release the nutrient into the water. However, the new research shows that mackinawite can continue capturing phosphorus even in these anoxic conditions. While iron-rich minerals usually trap phosphorus when oxygen is present, the discovery of mackinawite's ability to retain phosphorus under low-oxygen conditions adds a new layer to scientists' understanding of nutrient movement in freshwater ecosystems.
This finding could help improve predictions of lake recovery after phosphorus pollution is reduced and potentially enable lakes to recover more quickly than anticipated.
Written by urgent.news from Phys.org's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
