Scientists have uncovered a surprising discovery in the deep ocean: metal nodules, acting like batteries, generate oxygen without sunlight.
About half the oxygen we breathe comes from the ocean, but until now, we believed this oxygen was produced solely through photosynthesis by marine plants, a process requiring sunlight. In the depths of the ocean, where sunlight cannot penetrate, a new form of oxygen production has been found.
Led by Professor Andrew Sweetman of the Scottish Association for Marine Science, researchers discovered significant amounts of oxygen being produced near metal nodules, potato-sized lumps scattered across the seafloor. These nodules, formed over millions of years from dissolved metals in seawater, contain valuable minerals like lithium, cobalt, and copper, making them a target for deep-sea mining companies.
The researchers believe the metal nodules act like natural batteries, generating electrical currents that split seawater (H2O) into hydrogen and oxygen. This process, similar to electrolysis in a battery-powered torch, creates oxygen even in the absence of sunlight.
The discovery, published in the journal Nature Geoscience, has significant implications for our understanding of the deep ocean and the potential environmental impact of seabed mining.
"We need to explore this in greater detail and use this information if we are going to go into the deep ocean and mine it in the most environmentally friendly way possible," says Professor Sweetman.
The deep sea is a complex and largely unexplored ecosystem. New species are being discovered regularly, and it's estimated we know more about the Moon's surface than the depths of our own oceans. This discovery underscores the importance of protecting this environment, especially considering the potential risks associated with seabed mining.
Mining companies are already exploring the Clarion-Clipperton Zone, where this discovery was made, to extract the valuable minerals contained within the nodules. However, scientists warn that this activity could destroy vital ecosystems and disrupt the newly discovered oxygen production.
Over 800 marine scientists from 44 countries have signed a petition calling for a pause on deep-sea mining activities, highlighting the environmental risks involved. The US National Oceanic and Atmospheric Administration (NOAA) has also expressed concerns, warning that mining could lead to the destruction of life and habitats in mined areas.
Professor Murray Roberts, a marine biologist from the University of Edinburgh, states, "Thereâs already overwhelming evidence that strip mining deep-sea nodule fields will destroy ecosystems we barely understand. It would be crazy to press ahead with deep-sea mining knowing they may be a significant source of oxygen production."
This discovery highlights the need for caution and further research before proceeding with seabed mining. The deep ocean is a vital part of our planet, and understanding the role these metal nodules play in oxygen production is crucial to protecting this fragile environment. The potential impact of mining on both the oxygen production and the deep-sea ecosystem needs to be thoroughly assessed before any further actions are taken.
