AFP – Some six billion tonnes of sand and other sediment is extracted from the world’s seas and oceans every year, the United Nation (UN) said on Tuesday, warning of the devastating toll on biodiversity and coastal communities.
Launching the first ever global data platform on sediment extraction in marine environments, the United Nations Environment Programme (UNEP), warned that the scale of dredging was growing, with dire consequences.
“The scale of environmental impacts of shallow sea mining activities and dredging is alarming,” said UNEP’s Head of Analytics Centre GRID-Geneva Pascal Peduzzi.
He pointed to the effects on biodiversity, as well as on water turbidity, and noise impacts on marine mammals.
The new data platform, Marine Sand Watch, uses artificial intelligence (AI) to track and monitor dredging activities of sand, clay, silt, gravel and rock in the world’s marine environment.
It uses so-called automatic identification system (AIS) signals for ships combined with AI to identify the operations of dredging vessels, including in hotspots like the North Sea and the east coast of the United States.
“The signals emitted by the vessels allow access to the movements of every ship on the planet,” Peduzzi told AFP, adding that AI makes it possible to analyse the mountains of data gathered.
That process is still in the early stages, and so far, only around 50 per cent of vessels are being monitored.
But the platform estimates that out of some 50 billion tonnes of sand and gravel used by humanity each year, between four and eight billion tonnes come from the world’s oceans and seas.
“This represents six billion tonnes on average every year, or the equivalent of more than one million dump trucks every day,” Peduzzi said. He pointed out that our entire society depends on sand as a construction material, to make everything from schools, hospitals and roads to hydroelectric damn, solar panels and glass.
At the same time, sand plays a vital environmental role, including to protect coastal communities from rising sea levels. The UN is aiming to publish the 2020-2023 figures by the end of this year.
“But it is already clear that these activities are not slowing down, but rather are taking on gigantic proportions”, Peduzzi said. He warned that the world is approaching the natural replenishment rate of 10-16 billion tonnes of sediment washed into the world’s oceans each year.
While the tipping point has not been reached at a global level, he cautioned during a press conference that in some localities, “we are extracting it faster than it can replenish itself”.
“This is not sustainable.”
The North Sea, Southeast Asia and the East Coast of the United States (US) re among the areas with the most intense marine dredging.
China, followed by the Netherlands, the US and Belgium meanwhile have the biggest dredging fleets, a GRID-Geneva sand industry expert Arnaud Vander Velpen told reporters.
Peduzzi described extraction vessels as giant vacuums, cleaning seabeds, and sterilising them, warning that this leads to the disappearance of oceanic micro-organisms and threatens biodiversity.
Beyond presenting its figures, the UN said it hoped the new platform could lead to discussions with the sector, pushing businesses to move in a more environmentally friendly direction and improve their extraction practices.
