The Importance of Seaweed

Seaweed. What first comes to mind when I mention this strange and often misunderstood algae? Maybe you picture long strands of brown kelp with leathery fronds that you are forced to wade through during summer months spent swimming in the sea. Perhaps rock pools brimming with crimson red algae that glints in the sun’s heat come to mind. Or maybe you just see it as a nuisance as it grazes your leg on a long beach walk. For some people, seaweed acts as a source of food, a crispy snack sometimes known as ‘sea vegetables’ that is often served in western Chinese restaurants. Others use seaweed for its medicinal and herbal purposes, in wound dressings, dental moulds and microbiology as a culture medium. Some diet pills actually use seaweed extract, expanding the stomach to make you feel more full.

You might not think it, but with around 650 separate species of seaweed, the UK is considered a global diversity hotspot. In fact, because Sussex has an extensive coastal landscape of 50 miles, there is an entire marine rainforest equivalent lurking just underwater. Many people see them as useless, but this slimy and slippery algae are crucial components of ocean forests as well as shallow waters. It is estimated that 80% of the world’s oxygen comes from marine algae. This helps to lock up carbon dioxide within the seaweed, slowing down climate change. As the gas enters the water, it is absorbed into the leaves of the seaweed. With ocean water clean, marine animals can be similarly healthy. So, essentially, long as seaweed exists within an ocean ecosystem, biodiversity can be supported and encouraged to thrive.

As well as balancing the aquatic environment, it has been proposed that seaweed could combat climate change, for example it can be farmed as part of a programme called ‘ocean afforestation’, reducing carbon emissions from the surroundings. Afforesting just 9% of the ocean floor could store away up to 50 billion tons of carbon dioxide annually where otherwise it would build up in the atmosphere. UK researchers have also developed a simple way of processing seaweed before making bulk chemicals and biofuels from it. This process will remove plastic from the oceans and help to clean up tourist beaches worldwide. Additionally, seaweed has huge potential in a brand new industry that is generating increasing interest. Innovative packaging that is 100% biodegradable may be crucial to contribute to the global aim of establishing a sustainable future. Researchers increasingly focus on seaweed-based packaging that is not only biodegradable, but edible too!

Next time you encounter a piece of seaweed, try to think of its important contribution in the everlasting fight against global warming

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