Quick Definition
Dense underwater meadows of flowering plants in shallow coastal marine waters, serving as critical nursery habitat and carbon sinks.
📖 Full Definition
Seagrasses are the only true flowering plants (angiosperms) that complete their entire life cycle submerged in marine water. They form dense meadows (beds) in shallow, sheltered coastal areas. Seagrass beds are among the most productive and valuable ecosystems on Earth: they support over 30% of the world's fishing grounds, sequester carbon at 35× the rate of tropical rainforests, and provide critical nursery habitat for commercially important fish and invertebrates. Over 350 fish species use seagrass beds as nurseries. They have declined by ~30% globally since the 1930s.
💡 Examples & Context
European sea bass (Dicentrarchus labrax) juveniles spend 1–2 years in estuarine seagrass beds before migrating offshore.