Even the deepest, darkest corners of the ocean are not immune to human disturbance. Radioactive waste, chemical weapons, even scientific research can all mess with the ecosystems of the deep.
But the sea gives up its secrets grudgingly, and our impact on the ocean floor has mostly remained a mystery, until now. A team of British researchers, including Angela Benn from the National Oceanography Centre in Southampton, set out to determine the extent of man’s footprint on the sea floor.
The team selected the heavily-trafficked OSPAR maritime area of the Northeast Atlantic Ocean for the study. This region was a dumping ground for radioactive waste, and even chemical weapons between 1949 and 1982. It has also seen its share of oil and gas exploration, oceanographic research, and the construction of submarine communication cables during the last century.
For the most part, all of this activity has combined to inflict minimal to moderate disturbance.
Though spatially, radioactive waste damage extended over only .08 square miles, the long-term effects of the radioactive waste were troubling. Due to the slow decay of radioactive material, the waste could linger for hundreds to thousands of years.
But the most startling offender was bottom trawling, a method of deep sea fishing in which nets are dragged along the sea floor. Researchers estimate that up to 10,749 square miles were trawled, an area about the size of Massachusetts, with some areas raked by nets more than once per year.
In total, all the anthropogenic activities impacted only a small percentage of OSPAR’s 4,259,547 square-mile area, researchers reported in a new study in the journal PLoS ONE. But bottom trawling was by far the biggest culprit, accounting for all but a few square miles of impact.
The main message is that humans are already making a lasting impression on some of the deepest and most inaccessible corners of the planet. These places should be most sheltered from human activity, but in some cases the ravages of bottom trawling are so large they are visible from space. The fact that we are already carving up the deep sea is an indication of just how far-reaching man's footprint on the planet extends.
Image: PhillipC, Flickr
Tags: Conservation, Oceanography, Pollution
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