Seaweed

Algae and kelps represent the dominant plant species in the intertidal zone. All of these plants have specialized adaptations that protect them against drying when they are exposed during low tide. Most types of kelp are edible and are considered a food staple in parts of the world. Extracts from kelp and algae are used in the manufacture of ice cream and certain types of cosmetics.

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Red Coralline Algae

The red coralline algae belong to the phylum Rhodophyta. They can incorporate calcium carbonate into their cell walls, giving the body a rigid, segmented appearance and texture. Most of the red algae have the ability to carry on photosynthesis at much greater depths than other types of algae. Some species from the Bahamas grow at depths of nearly 270 m (880 ft).

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Green Algae

These green algae, shown here exposed at low tide, belong to one of some 6,000 to 7,000 species of plants that make up the phylum Chlorophyta. Organisms in this phylum may appear as single cells, amorphous sheets, or collections of long filamentous strands. Although able to survive in marine and fresh waters, damp soil, or snow and ice, most species are found in freshwater habitats.

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