New Study Reports Potential for Deepsea Mining Damage

mineral nodules

Published Feb 12, 2017 2:00 AM by The Maritime Executive

A new international study has demonstrated that deepsea nodule mining will cause long-lasting damage to deepsea life. This study, led by scientists at the National Oceanography Centre (NOC) in the U.K., was the first to review all the available information on the impacts of small-scale sea-floor disturbances simulating mining activity. 

The experiments evaluated were much smaller than any planned mining program, which may impact an area the size of London every few years, but they show that the amount and diversity of marine life was reduced by the action of mining, often severely and for a long time. 

The oldest experiment, assessed 26 years after the impact, still leaves an obvious disturbance on the sea-floor, and both the number of animals and species present in the disturbed area was reduced. Although some evidence of recovery was found, very few types of animals returned to previous levels even after decades.

New sources of high-quality reserves of metals are now being sought, including the huge expanses of nodules covering significant amounts off the global deep sea floor. These nodules are potato-sized rocks, containing high levels of metals, including copper, manganese and nickel, which grow very slowly on the sea bed, over millions of years. 

Although no commercial operations exist to extract these resources, many are planned. The International Seabed Authority, which manages this area, has issued exploration licenses across the central Pacific to a variety of countries, including the U.K. 

However, exploiting these resources will have an environmental cost, says Dr Daniel Jones from the NOC, the lead author of the study. “The deepsea is a remote, cold and dark environment kilometers below the surface of the ocean, yet it is home to a wide variety of marine life, much of which is very poorly understood. This research analyzed all available studies on impacts to ecosystems in nodule areas and shows mining for nodule resources on the seafloor is likely to be highly destructive in the mined area, with long lasting impacts. 

“We also think that these studies will underestimate the impacts of mining. Many would not even represent one month’s work for a full-scale commercial operation, which might last for twenty years.”

Similar warnings have been made by scientists working on the MIDAS project.

Professor Edward Hill, Executive Director at the NOC commented, “By 2050, there will be nine billion people on earth and attention is increasingly turning to the ocean, particularly the deep ocean, for food, clean supplies of energy and strategic minerals. The NOC is undertaking research related to many aspects and perspectives involved in exploiting ocean resources. This research is aimed at informing with sound scientific evidence the decisions that will need to be taken in the future, as people increasingly turn to the oceans to address some of society’s greatest challenges.”

The study is published in the international journal PLOS ONE.