Brown Algae (Phaeophyta)

The Brown Algae are almost exclusively marine, the few fresh water species being quite rare. It is the largest, most complex type of algae. The largest brown algae may reach over 30 meters in length.

They are the dominant seaweeds in the colder waters of the northern hemisphere. They grow attached to the rocks, shells, or coarser algae such as the kelps.

Members of the group dominate many benthic marine biotas, sometimes reaching from the ocean floor to its surface. In general, they are not free-floating organisms, but are attached to rock, coral, or other firm surfaces.

One kind, Heribaudiella, is of particular note. It forms a relatively large disc shape crust of dark color on stones in rapidly flowing upland streams. The pigments of Phaetophytes include chlorophyll A and C, carotene and xanthophylls, including fucoxanthin. The last mentioned pigment predominates to give the characteristic brown color.

Food reserve is maintained in forms of sugar. The brown algae reproduce by vegetative, asexual and sexual means of reproduction.

End of Basic Water Science

More about Algae…
Red Algae
Significance of Algae

Next Topics…
Fungi
Liverworts and Mosses
Vascular Plants

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