SEAGRASS has been hailed both as conservation鈥檚 and its 鈥渦gly duckling鈥�. Since 1980, the world has been losing this flowering marine plant to pollution, disease and human disturbance at a ; in the UK, there has been a decline of nearly 92 per cent in the past century. But seagrass is a habitat that than tropical rainforest. If silver bullets exist in conservation, could seagrass claim that title?
Though it covers just , seagrass flanks coastlines across every continent except Antarctica. Its , and it has evolved into . It appears unassuming, yet a cross-section of a meadow would reveal an architectural masterpiece of horizontal roots and 鈥渞hizomes鈥�, which form often-ancient highways of nutrition throughout the seabed.
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Carbon deposits within these rhizomes in Spain鈥檚 have amassed into a layer over 10 metres thick and 6000 years old. Earlier this June, a single specimen of seagrass was that is estimated to be around 4500 years old and spans about 180 square kilometres.
The subterranean root system can stabilise coastlines in the face of storm surges and floods, both of which are more frequent in a warmer world. Carbon stockpiles latticed below meadows are also . have found how increased sediment levels can reduce water currents and wave energy, softening the impact of climate-induced sea level rise.
Seagrass can also help with ocean acidification. Since the industrial revolution, has increased by 30 per cent, due to dissolved carbon dioxide becoming carbonic acid. This lethal chemical imbalance , bivalves and molluscs. But a healthy seagrass bed can help neutralise acidic seawater. A compelling found seagrass reduced local acidity by up to 30 per cent.
, yet seagrass could provide an answer here too. found established meadows can trap, sort and sieve microplastics into 鈥淣eptune balls鈥�. Up to 900 million plastic items are thought to be collected in these fibrous bundles every year.
The UN Environment Programme states that will contribute to reaching 10 of its sustainable development goals. Members of the public are helping re-seed meadows. The UK鈥檚 was inspired by a , which restored the largest area of seagrass in the world. And the UK charity Ocean Conservation Trust recently allowed the Blue Meadows project to build the country鈥檚 largest seagrass nursery, in a 400-square-metre plot.
So, have we found our elixir? Hailing anything as a single remedy risks dismissing conservation efforts as simple, achievable solutions. Amid the climate and biodiversity crises, a false sense of security is deadly, not least as it would place faith in a habitat that is disappearing at a global rate of 7 per cent per year. Seagrass needs to be safeguarded alongside coral reefs and mangroves: just 26 per cent of its recorded meadows fall within Marine Protected Areas, compared with 40 per cent of coral reels and 43 per cent of mangroves.
But the implications of restoring seagrass can鈥檛 be ignored. With its rate of carbon burial and its ability to stabilise and elevate the seabed and halt marine plastic in its tracks, there is danger in delay. And what better approach to habitat restoration and climate change mitigation than a grassroots one?
Sophie Pavelle is author of
