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How do coralline red algae help form coral reefs and coral sands?
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Algae
The macroscopic genus of algae known as Acetabularia is commonly called “mermaid's wine glass” because of the distinctive umbrella-like shape of the tips of its stalks.
Coralline red algae are essential contributors to the development and structural integrity of coral reefs. Unlike many other algae, these organisms deposit calcium carbonate within their cell walls, causing their thalli to become hard and brittle.1
Their role in reef formation includes:
- Structural Reinforcement: Coralline algae act as a binding and cementing agent, helping to hold together the various components of the reef, such as coral fragments and other calcareous organisms. In high-energy environments, such as areas with strong surf, these algae can be even more critical than corals in maintaining the reef's structural framework.2
- Reef Accretion: By secreting calcium carbonate, they contribute directly to the growth of the reef matrix.1
- Sediment Contribution: As these algae grow and erode, they provide calcareous fragments that fill the gaps between coral colonies. These fragments, along with the remains of other shelly and calcareous organisms, accumulate to form the carbonate sands and muds associated with reef complexes.23
Through these processes, coralline red algae help stabilize the reef environment and facilitate the formation of islands and cays.43