The oceanographic mission that takes place 1,500 kilometres off the Mexican coast aims to investigate and monitor the environmental impacts of polymetallic nodule mining in the deep sea of a pre-prototype ore collection vehicle.
"The intention of the project is to assess the impact of the nodule extraction vehicle on marine organisms and provide the international authority with the scientific basis to legislate on mineral exploration of the ocean floor" revealed a researcher from the Marine and Environmental Research Centre (CIMA) of the University of Algarve to Lusa.
Nélia Mestre said that restrictions on international travel due to the Covid-19 pandemic prevented Portuguese researchers "from being on board the ship" Island Pride which should leave the port of San Diego, California "this week" with two remotely operated vehicles (ROVs) and an autonomous underwater vehicle (AUV) on board.
The 20 or so Portuguese researchers will have to wait a few weeks for samples of "corals, ophiurids, sponges, plankton and amphipods" collected by their German, Dutch and Belgian colleagues, before they can start their work, he said.
"They will study zones with and without the impact of the nodule-collecting robot, collect the samples from various sites and we will assess the impact of the sediment cloud in terms of ecotoxicity, physiology and biodiversity," he revealed.
Nodules are clumps of metal "lying on the surface" on the ocean floor and formed by "the precipitation of metals" and which gather "over thousands of years".
These structures are very appealing to industry because of their composition of "manganese, nickel, copper and cobalt". They are removed by a robot that "sucks them to the surface" and it is precisely the impact of this extraction that the researchers intend to study.
"As the sediments are very fine, the simple movement of the device on the bottom raises a cloud into the water column, not knowing its real dimension, where it will move and what its effect will be on organisms," he clarified.
The area where the study will be carried out is "all under concession for exploration", which has not yet begun as there are no "specialised machines" to do so.
This is an independent investigation but carried out in partnership with the company that is developing the extraction robot with the intention of improving the existing prototype and "introducing corrections to minimise impacts that may be detected".
The impacts of a study carried out in the eighties with a trawl extraction revealed that four decades later "there was no recovery of the habitat", and the "marks from the removal of the nodules" are still visible.
CIMA-University of Algarve, Portuguese Institute of Sea and Atmosphere (IPMA), IMAR-University of Azores, CESAM-University of Aveiro and Ciimar-University of Porto, are the five Portuguese institutions involved in the project, which also includes entities from Germany, Netherlands, Belgium, Norway, France, Italy, United Kingdom and Poland.