It won’t come as a surprise to many to know that the impact we are having on our ocean’s deep seafloor is growing with each decade that passes. New findings have revealed for the first time the actual physical footprint we are leaving on the oceans seafloor, and the biggest problem area is bottom-trawling commercial fishing fleets.
New research conducted by researchers from the National Oceanography Centre in Southampton, UK, have analysed the deep seafloor of the OSPAR maritime area of the North East Atlantic Ocean, where human activity has been particularly intense. The area covers eleven million square kilometres, of which 75% of which is deeper than 200 metres and includes important fishing grounds.
“Information on the location and spatial extent of human activities affecting the deep-sea environment is crucial for conservation of seafloor ecosystems and for governance and sustainable management of the world’s oceans,” said Angela Benn of the National Oceanography Centre, who led the new study.
The researchers used data available for the year 2005 and mapped out and estimated the spatial extent of intentional human activities occurring directly on the seafloor, as well as structure and artefacts present on the seafloor from past human activities.
Instead of including the ecological effects such as contamination and pollution, they excluded these and focused on the physical footprint, the easier of the two areas to investigate.
That being said, gathering all the information they needed was not as straightforward as they had hoped:
“Some governments, public organisations and private companies were far more forthcoming with information than others,” explained Benn. “Significant improvements are needed in data collection and availability, and this requirement needs to be built into international conventions and treaties with a legal framework in place to ensure informed environmental management.”
Which Human Activities Have the Greatest Impact on the Ocean Floor?
The researchers’ assessment suggests that previously dumped radioactive waste, munitions and chemical weapons together have the lowest physical footprint of the human activities considered. Non-fisheries marine scientific research also had a small footprint, though the scientific research of fishery vessels, telecommunication cables and the oil and gas industries all had a moderate impact on the seafloor.
Not surprising, though, was the fact that even on the lowest estimates, the impact that bottom trawling fishing is having on the sea floor is at least ten times that for the other activities assessed, with a physical footprint greater than all the other combined.
Their conclusions were that the total area of physical imprint in 2005 was approximately 28,000 kilometres squared, though this can only have since grown over the second half of the decade. Demand continues to grow and so will humans expansion into deeper waters.
“Consequently,” argues Benn, “there needs to be a much greater understanding of the relative impacts of human activities on the deep seafloor, and in particular how these activities affect seafloor ecosystems and biodiversity.”
Source: National Oceanography Centre in Southampton, UK
Image Source: Institute of Marine Research, Norway
