As the cells die and the ice to which they adhere along the bottom melts, they stick together to form clumps that can sink thousands of feet to the sea floor in a single day. There they constitute an important food source for bottom-dwelling animals and bacteria.
In addition to food, the lumps also transport a questionable cargo to the Arctic’s deep seas: microplastics. This emerged from a study led by biologist Dr. Melanie Bergmann of the Alfred Wegener Institute Helmholtz-Zentrum für Polar- und Meeresforschung (AWI).
“We finally found a plausible explanation for the fact that we always find the largest amounts of microplastics in the ice-edge region, even in deep-sea sediments,” Bergman said.
Until now, researchers only knew from previous measurements that microplastics are concentrated in the ice during sea ice formation and are released into the surrounding waters when the ice melts.
“The speed at which the algae sinks means that they fall almost in a straight line below the edge of the ice. Bulk clumps of algae called sea snow, on the other hand, sink more slowly and are pushed aside by the current, so that sea snow moves away. It ends up.” The fact that the blocks milocera Carrying microplastics directly to the bottom helps explain why we measured higher numbers of microplastics just below the edge of the ice.”
