Although algae classification
has changed through the years, algae are traditionally placed
in the kingdom of plants because of their similarity to land
plants and their photosynthetic properties.
Among the main divisions of the algae group, it is worth
CHLOROPHYTA, green algae (1200 species). About
90% of green algae live in freshwater. The typical green color is the
result of the dominant pigment of chlorophyll.
PHAEOPHYTA, brown algae (1200 species). They
are always marine with some rare exceptions and reach their greatest
abundance in cold temperate waters. They come in a wide variety of shapes
and are the largest seaweeds found in the oceans. Kelp (Laminaria)
forest of California or chilean coasts are up to 50 meters long. Wracks
is the common name given to Fucus group.
The Sargasso sea, often associated with the notorious"Bermuda Triangle" is
so named due to the accumulation of a strange forest of Sargassum seaweeds.
RHODOPHYTA red algae (6500 species). Most of
them are marine. The red color is due to the larger amount of red phycoblin
pigments. They offer the most unimaginable range of reds. Two extracts
of red algae, agar and carrageenan have a great significance on the international
economy of seaweed and its derivatives. Therefore, farming and harvesting
of red algae are developing in numerous areas of the world. Nori (Porphyra
sp.), dulse (Palmaria palmata) are edible seaweeds considered as a delicacy.