Coral reefs are often called the 'rainforests of the sea' due to their incredible biodiversity. These underwater ecosystems are built by tiny animals called polyps, which secrete calcium carbonate to form hard structures. They provide homes and food for a quarter of all marine species, despite covering less than 0.1% of the ocean floor. Besides supporting marine life, coral reefs protect coastlines from erosion and storms, and they are a source of new medicines. However, they are highly vulnerable to rising ocean temperatures, pollution, and ocean acidification, which leads to coral bleaching and eventual death. Scientists are working on various conservation efforts, including restoring damaged reefs and educating people about their importance.
Yukarıdaki parçaya göre, mercan resifleri hakkında aşağıdakilerden hangisi kesinlikle doğrudur?
A) They cover most of the ocean floor and are home to all marine species.
B) Their main function is to attract tourists and divers.
C) They are built by large marine mammals and are immune to climate change.
D) They are vital ecosystems that support biodiversity and protect coastlines, but face significant threats.
E) They are primarily a source of calcium carbonate for industrial use.