• Definition: Known as the "rainforests of the sea" due to their rich biodiversity. They house nearly a million species of plants and animals. Major coral reefs include the Great Barrier Reef, the reefs around the Philippines and Indonesia, Tanzania and the Comoros, and the Lesser Antilles in the Caribbean.

Real-world Example: The Great Barrier Reef in Australia is a thriving ecosystem that supports a wide variety of marine life.

• Value: Coral reefs have significant environmental and economic value.

  • Biodiversity: Coral reefs provide breeding grounds for many fish species.

  • Seafood: Contribute to about one-quarter of total fish catch in LICs.

  • Medicinal potential: Coral reef species produce an array of chemicals for self-protection that could be useful in medicine.

  • Other Products: They yield corals and shells for jewelry and curios, live fish and corals for aquariums, and sand and limestone for construction.

  • Recreational Value: Major attractions for tourists, especially snorkelers and scuba divers.

  • Coastal protection: They buffer shorelines from wave action and storm impact.

Real-world Example: The Great Barrier Reef contributes around A$4.6 billion annually to Queensland's economy, mainly from tourism.

• Threats: Overfishing, pollution, and rising levels of greenhouse gases, causing oceanic acidification and warming oceans, leading to coral bleaching.

Real-world Example: The 1997-98 El Niño coincided with a global coral bleaching event, killing about 16% of corals.

• Conservation measures: Marine protected areas (MPAs), stricter regulations on fishing vessels, use of technology like satellites and drones for monitoring, and local initiatives like painting fishing vessels according to their fishing permissions.

Real-world Example: In 2010, under the UN Convention on Biological Diversity, the Aichi Targets were agreed upon, aiming to have 17% of inland water and 10% of coastal and marine areas under conservation by 2020.

• Definition: Mangroves are salt-tolerant forests growing in tidal estuaries and coastal zones of tropical areas, such as the 570,000 ha Sundarbans in Bangladesh.

• Value: Provide large quantities of food and fuel, building materials, and medicine. Also, protect coastlines, absorb nutrients from farming and sewage, and house a diverse array of organisms.

Real-world Example: In the Philippines, a single hectare of mangrove can yield 400 kg of fish and 75 kg of shrimp annually.

• Threats: Many mangrove areas have been lost to rice paddies, shrimp farms, and urban expansion. Pollution from rapid population growth also affects mangroves.

Real-world Example: Caribbean and South Pacific mangroves have mostly disappeared, while India, West Africa, and South East Asia have lost half of their mangroves.

• Conservation measures: Sustainable management, restoration and afforestation, managed realignment, flow restoration, and legislative protection.

Real-world Example: The Diawling National Park in Senegal, where mangroves were restored by artificial flooding after a dam construction caused the wetland to dry out, and the mangroves suffered.

Remember to always apply your knowledge of these ecosystems to real-world contexts, such as how coral reefs support local economies and how mangroves protect against natural disasters. Understand the threats these ecosystems face and the conservation efforts underway to protect them.