From Ash to Extinction: Volcano Impact on Deep Sea Ecosystems

Deep beneath the ocean surface, organisms that feed on materials emitted from hydrothermal vents suffered from the consequences of the 2022 submarine Hunga Tonga volcanic eruption.
The Hunga Tonga volcanic eruption,broke several records. During the eruption, there were lightning flashes in the volcanic plume, reaching a peak of more than 2,600 flashes per minute.

In addition, the submarine volcano located about 30 km south of the main island in the Polynesian archipelago produced a plume of ash, water and volcanic gas at least 60 km high, the largest eruption observed in the modern satellite era.
That the powerful eruption had effects also in its depths.
A significant amount of sediment reached the shores of islands more than 100 km from the eruption epicenter.

It is like a leaf falling from a tree, carried by winds and currents to a completely different place,” said Professor Thomas Giacchetti from the Department of Earth Sciences at Oregon University, who led the study.
The study examined the geological and biological effects of volcanic sediment movement.
The research findings also shed light on the consequences of human deep-sea mining, which could increase harm to organisms living in these layers.

Recent studies have shown that bout 90% of marine organisms live on the seafloor, according to the World Wildlife Conservation Foundation.
Many species on the ocean floor are plankton feeders, invertebrates that feed by filtering and attaching to the seabed, capable of sucking up small creatures or floating food particles through gills. “Due to sediments from the Hunga-Tonga eruption, the gills of these organisms may become blocked, which will dramatically affect their ability to generate energy,” said Chacknova.

According to World Bank data, the fishing industry is essential for the subsistence of Tonga’s residents. Estimates indicate that 82% of Tongan households are involved in the fishing sector.
In addition, marine tourism accounts for more than 7% of the country’s gross domestic product. “Although this eruption occurred on the seafloor, it has a chain of effects,” said Chacknova. “Beyond the loss of electricity or Wi-Fi due to damaged submarine cables, the livelihoods of people who rely on fish for food were affected.

Fishing is crucial for Tonga’s economic and nutritional security.”
As the world moves toward a greener future, demand is increasing for minerals used in renewable energy and electric vehicles.
Large deposits of metals like copper and cobalt, potato-sized, are buried beneath the ocean floor.

Small Pacific nations, like Tonga, have already received approaches from private companies presenting this as a huge economic opportunity.
However, some express concerns, because deep-sea mining can stir up plumes of sediment that take a long time to settle.