From underwater tunnels to bridges to communication cables snaking across the ocean floor, structures made by humans are encroaching on marine life at an ever-growing pace. Our physical footprint of marine construction covers an area of 32,000 square kilometers (12,000 square miles) on the seafloor globally, according to a recent study in Nature Sustainability. The study marks the first time that the impact of marine structures on our global seascape has been quantified. Researchers from the University of Sydney, Australia, collaborated with an international team to synthesize the available global data on marine structures and used it to come up with a conservative estimate of sprawl size.
Despite limitations and gaps in information, the map provides a valuable jumping-off point for future efforts to minimize the damaging impacts of human construction on marine ecosystems, said lead author Ana Bugnot, a marine ecologist at the University of Sydney. “There’s an idea that the ocean is vast, and no matter what we do we’ll never destroy it,” Bugnot said. “If we can get an estimate of how much we’ve damaged the environment in a number, people are more likely to pay attention.”
According to the study, most marine construction—a term that encompasses marinas, commercial ports, oil rigs, and more—is located within the Exclusive Economic Zones belonging to coastal nations. In the United States alone, more than 50 percent of the country’s natural shoreline has been replaced by structures, such as seawalls and breakwaters. Aquaculture farms, where workers produce seafood from shrimp to clams to fish, account for many of the marine structures today. However, the study projects that structures related to alternative energy, such as windmill platforms and tidal farms, will grow most quickly going forward—expanding in area as much as 208 percent each year.
Source: Mongabay
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