What is seagrass?

Seagrass are another unique ecosystem found underwater: they are the only flowering plant found in the marine environment.

Seagrass have root, stems and leaves called blades, and they are usually found in shallow, near-water shores in many parts of the world. Seagrass can grow and form dense meadows, some even large enough to be seen from space.

Currently, there are approximately 60 species of seagrass.

How do seagrass live?

Seagrass conduct photosynthesis with the help of sunlight. Besides needing sunlight, they also need carbon dioxide, clean and shallow water as well as nutrients to grow.

They reproduce by releasing pollen from flowers, which is then fertilised into seeds that are dispersed by seawater, to grow elsewhere. Animals that eat seagrass seeds and egest them can also aid in dispersal.

Why are seagrass important?

Every day, 10 litres of oxygen that we need is generated through photosynthesis of 1m2 of seagrass.

As the amount of carbon dioxide in our atmosphere is increasing, it must be noted that seagrass also absorbs this carbon: 15% of the total ocean carbon absorption is done by seagrass!

Besides relying on coral reefs as a nursery, more than 20% of the world’s fisheries regard seagrass as a critical nursery habitat. Its loss would mean these important species that we call our food would not have a place to grow safely. Apart from that, hundreds of thousands of marine species live, breed and feed in seagrass areas.

What are the threats that seagrass face?

Rising ocean temperatures caused by climate change is one global threat that seagrasses face. Wind-driven waves and storms can also be so severe that it could damage seagrass meadows.

Some local threats faced by seagrasses include physical destruction from coastal development, dredging, trawling boats, as well as boat anchors and propellers.

Land-based pollution is a huge threat to seagrass: sedimentation, intreated sewage and fertiliser runoff as well as industrial waste cause the quality of seawater to worsen, making it difficult for seagrass to grow and thrive. Just like corals, seagrasses are also threatened by disease outbreaks and invasive species.

What can we do to protect seagrasses?

One immediate action we can take to protect seagrasses is to reduce pollution and improve current waste management programs. Just like coral reefs and mangroves, seagrasses are also unable to thrive in waters that are murky, dirty, polluted with rubbish and have high nutrient content.

Often neglected, it is time to look into incorporating seagrass meadows into Marine Protected Areas (MPAs). The impact to seagrasses should also be evaluated in development plans or EIAs (Environmental Impact Assessment).

We’re also encouraged to participate in conservation and restoration projects, which would then help in keeping us aware and better informed, enabling us to spread the word about these precious ecosystems. We at Reef Check Malaysia is working on monitoring the seagrass meadows in South of Johor in order to develop a comprehensive conservation strategy for coastal marine ecosystems.

As consumers, choosing Green Fins operators and sustainable resorts while on holiday also makes a big difference as sustainable tourism practices can help to reduce impact on our environment.