The plant that just keeps on giving
Seagrasses are one of the most valuable and biodiverse habitats on the planet and are one of the few habitats that provide multiple benefits to the environment.
Here’s some of the ways this wonder plant supports a healthier Ocean.
Seagrass meadows provide nurseries for commercially important fish, ensuring food security and supporting local economies. Healthier seagrass meadows create healthier fish stocks, which in turn creates a better economy for local fishing communities.
A single hectare of seagrass can support 80,000 fish and 100 million small invertebrates. Seagrass also provides a habitat for rare and endangered species such as seahorse and stalked jellyfish.
Seagrass meadows combat climate change by absorbing and storing huge amounts of carbon. They are up to 35 times more efficient at absorbing carbon than rainforests of the same area, and despite only covering 0.2% of the Ocean floor, seagrasses store 10% of the Ocean’s carbon.
Seagrass meadows are very efficient nitrogen strippers, removing chemical elements that cause harmful algae blooms that have negative influence on human and animal health.
Seagrass can reduce the indirect effect of coastal erosion, through their capacity to stabilise and maintain sediments on the seabed. They also improve water clarity and quality by capturing organic material, sediments and nutrients that flow in the water through the meadows.
Since the 1930’s, up to 90% of Zostera marina seagrass beds have been lost, largely through physical disturbance, pollution and disease.
When seagrass meadows are damaged or degraded, they capture less carbon and release significant amounts of greenhouse gases, carbon dioxide, methane and nitrous oxide that might have been stored for thousands of years.
The threats to seagrass
- Annual decline – The International Union for the Conservation of Nature (IUCN) estimated in 2014 that seagrasses are declining by 7% a year globally. This estimate makes it the fastest disappearing habitat on the planet. In the UK alone, we are losing around 500 hectares of seagrass meadows every year.
- Human impact – The biggest issues facing seagrass habitats come from human impacts, due to physical disturbances, such as boats anchoring and destructive fishing activity, as well as degradation of water quality due to sewage and agricultural run-off.
- Seagrass location – One of the key issues is that boat users don’t know where the seagrass meadows are and therefore don’t realise the harm is being done to them when anchoring or fishing.
- Alternative anchoring – Another challenge is providing low impact alternatives to anchoring in seagrass meadows. (Explore our work on AMS).
This is why we’re acting to protect what we have, and restore what we’ve lost. To find out about our latest seagrass project, Blue Meadows, click here.