Seagrass helps tidy up plastic from Mediterranean Sea
Seagrass might not seem like it’s capable of much, but it is incredibly successful at cleaning plastic from the sea.
It’s no secret that we appear to be drowning in plastic. The International Union for the Conservation of Nature (IUCN) estimates that 229,000 tonnes of plastic leak into the Mediterranean Sea each year, equivalent to 500 shipping containers worth of plastic spilling into it each day.
This all adds up over time. In fact, it’s such a serious issue that we wrote at length recently about an Italian architect’s plan to help sweep plastic from this corner of the globe. But help is at hand, from a place few might expect. Learn about the power of super seagrass.
The International Union for the Conservation of Nature (IUCN) estimates that 229,000 tonnes of plastic leak into the Mediterranean Sea each year, equivalent to 500 shipping containers worth of plastic spilling into it each day.
Seagrass is nature’s sweeper
If you’re looking for a fascinating story of evolution, it all starts on the shallow depths of the sea with seagrass. Serving as a useful moniker to represent over 60 species of marine plant life, seagrass started life on land, as plants which opted to colonise the oceans, up to 100 million years ago.
Seagrasses are typically long, green and narrow, growing in meadows, much like the grasses you find on land. The only difference is that they have evolved to pollinate themselves in water, and their leaves are able to adapt to the salty sea water that washes over them. All sorts of flotsam and jetsam can get caught in the leaves as a result, giving seagrasses something of a reputation as a sweeper of the ocean.
This comes in useful, especially when it comes to plastic waste, because much of the world’s plastic waste which ends up in the ocean has to pass through the shallows, before ultimately being deposited on the seafloor in the deepest depths. When passing through the shallower parts of our seas and oceans, plastic waste can get caught in the dead leaves of seagrasses.
When they die, seagrasses detach from their roots to form balls made of decomposed vegetable fibres. These ‘Neptune balls’ roll around the shallows, before being washed ashore like a form of marine tumbleweed.
Great balls of Neptune
Neptune balls are especially effective at collecting pieces of plastic and helping wash them back to shore, according to an article in the Scientific Reports journal. Researchers found as many as 1,470 items of plastic per kg of plant material, and the article estimated that seagrasses could be collecting up to 900 million plastic items from the Mediterranean Sea each year.
In effect, seagrasses are carrying out something of a spring clean of the seafloor, sweeping plastic into neatly bundled balls of densely-packed plant matter, which can be easily flushed out of the seas and back to shore. Imagine the effect this has on minimising ingestion of plastic by marine life, and you start to see nature finding an ingenious way of counteracting our polluting behaviours.