丝状红藻在礁石上覆盖死亡的角珊瑚骨骼

tous red algae (Rhodophyta) smothering the skeletal remains of a dead gorgonian coral on an Andaman Sea reef. Reduced to its base, the gorgonian is fully colonised by dense algal mats. Filamentous Rhodophyta spread rapidly on dead coral when herbivore populations decline and nutrient runoff rises, blocking juvenile coral recruitment. Gorgonian colonies take decades to grow; their loss removes reef habitat structure that cannot quickly be replaced. Close-up wide-angle shot from scuba diver point of view. 4K, static. Ko Haa Islands, Andaman Sea, Krabi Province, Thailand.