Plastic debris concentrates on the surface of the ocean via the currents of ocean gyres, with agglomerations shockingly visible from space. Plastic pollution further flows into the deep sea, following the same currents that historically have provided nutrients.
Though plastic takes a grievous toll on sea life, the open ocean where plastic concentrates is not the center of marine life on the surface. The deep sea is different. The hotspots of plastic deposits in the deep-sea are the same hotspots of benthic life. “Bottom currents are efficient conveyors of nutrients and oxygen, and consequently they dictate the location of important biodiversity hotspots. Unfortunately, the same seafloor currents also transport and emplace microplastics,” writes British geologist Ian Kane. Poison plastic becomes incorporated into the deep-sea food supply, thereby decimating benthic ecosystems for the sake of our momentary convenience.
References:
Ishi Nobu, “Plastic,” in The Fruits of Civilization (2019).
Ian A. Kane et al, “Seafloor microplastic hotspots controlled by deep-sea circulation,” Science (5 June 2020).
David Mohrig, “Deep-ocean seafloor islands of plastics,” Science (5 June 2020).