Seagrass - Ocean Central
Seagrass
Seagrass meadows are critical underwater ecosystems consisting mainly of flowering marine plants.
Often mistaken for seaweed, seagrasses differ by rooting themselves into the seabed, thriving in shallow coastal waters like bays, lagoons, and estuaries. Found across 159 countries, these ecosystems cover over 300,000 km² — an area roughly the size of Italy. However, these vital habitats are poorly mapped, limiting our full understanding of their global extent.
Seagrass by the Numbers
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18% of Ocean Carbon Sequestered
Seagrass meadows sequester up to 18% of the ocean’s carbon, despite covering just 0.1% of the seafloor, highlighting their critical role in climate regulation.
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Found in 159 Countries Worldwide
Seagrass meadows are distributed across 159 countries on every continent except Antarctica, illustrating their global significance in marine ecosystems.
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29% Decline Since 1879
Since 1879, the global area of seagrass has decreased by approximately 29%. However, some regions have begun to see a reversal of this trend since the 2000s, indicating potential for recovery.
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Nursery Habitat for 20% of Major Fisheries
Seagrasses provide essential nursery habitats for over 20% of the world’s largest 25 fisheries, underlining their importance in supporting global fish populations.
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30% Restoration Goal
Restoring 30% of seagrass ecosystems globally requires a coordinated strategy that combines ecological restoration of seagrass meadows with the reduction of harmful human activities that threaten these vital habitats.
Key Benefits of Seagrass Meadows
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Carbon Sequestration
Despite covering only 0.1% of the ocean floor, seagrass meadows store up to 18% of oceanic carbon, capturing carbon up to 35 times faster than tropical rainforests. Their sediments never become saturated, allowing continuous carbon storage.
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Coastal Protection
Seagrass roots stabilize sediments, acting as natural buffers against erosion, storm surges, and flooding, reducing wave energy before it reaches shorelines.
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Ocean Acidification Buffering
Through photosynthesis, seagrasses increase seawater pH, helping to counteract ocean acidification and creating healthier environments for marine life.
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Water Quality Improvement
By filtering nutrients, pollutants, and sediments, seagrasses enhance water clarity and quality, benefiting coral reefs and marine life.
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Biodiversity Enhancement
Seagrass meadows provide vital habitats for thousands of species, including endangered species like sea turtles, dugongs, and seahorses, supporting rich biodiversity.
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Sustaining Fisheries
As nurseries for juvenile fish, these meadows support over a fifth of the world’s major fisheries, contributing significantly to global seafood supplies.
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Ecotourism and Recreation
Seagrass meadows attract tourists for snorkeling, diving, and wildlife viewing, offering ecotourism opportunities that bolster local economies.
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Economic and Medicinal Benefits
Seagrasses have potential medical uses due to their antibacterial and anti-inflammatory properties. In some cultures, seagrasses have been used for traditional medicine and as material for crafts.
Pressures on Seagrass Meadows
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Coastal Development
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Climate Change
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Water Pollution
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Unsustainable Recreation
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Overfishing and Trawling
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Invasive Species and Disease
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Hydrological Changes
Taking Action to Restore Seagrass
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Protect Existing Meadows
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Seagrass Planting
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Support Natural Regeneration
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Promote Sustainable Practices
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Nature-Based Solutions
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Incorporate Seagrass in Climate Strategies
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Marine Spatial Planning
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Community Engagement
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Financial Incentives
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Strengthen Policies
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Research and Monitoring
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International Collaboration
Credits
- Carlos Duarte
- Vanesa Chalastani
- Letizia Valluzzi