Zostera Marina - Sea grass
This newsletter's featured species has shot to prominence in recent weeks due to its critical role in climate change. A recent study led by Florida International University has discovered that seagrasses can store up to twice as much carbon per square kilometre as a land-based forest. By trapping sediments, seagrass meadows are now increasingly recognised as natural hotspots for carbon sequestration.
Sea grass meadows have been recorded in coastal waters around the south of Arran and off Pirnmill to the North West of the island. There are two types, one short and hardy - Zostera noltii - and the longer Zostera marina, which looks much like a tangled thicket of grass and grows in deeper parts of the seabed.
They stabilise sandy sediments and provide habitat and nursery grounds for commercially important species of fish and crustaceans. Unfortunately seagrass meadows are in decline due to pollution, dredging and other marine activity which damages the seabed. It is estimated that 29% of historic seagrass meadows have been lost globally and will continue to shrink by 1.5% annually.
The science which has now linked seagrass meadows with carbon storage will only further strengthen the case for their protection in years to come as government and industry seek to reduce greenhouse gas emissions.
Latin name: Zostera marina
Habitat: found on sands and fine gravels in shallow and often sheltered subtidal waters up to 8 metres deep on spring tides.
Diet: Buoyant leaves shoot from a mat of seagrass roots and these leaves draw energy from the sun by photosynthesis.
Size: seagrass leaves can grow up to 1m in length
For more information see: