Seaweeds are macroalgae which are found attached to substratum in benthic habitats.
They are multicellular autotrophic photosynthetic plants contributing significantly to the
primary production of the marine ecosystem. They are non-flowering plants without true
roots, stems, leaves and attached to substratum by means of holdfast. They are a significant
feature of most shorelines and shallow water environments throughout the world (Robin
South, 1993). They can be found mainly in intertidal and in the sub-tidal region up to a depth,
where 0.01 % photosynthetic light is available (Domettila et al., 2013). They have an
ecological role of providing habitat and substrata for invertebrates, fish, mammals, and birds
(Vásquez 1992; Graham et al., 2007) and a source of food for many grazing vertebrates and
invertebrates
