Aquatic ecology and Biodiversity

Unit 11- Intertidal zone

11.2.2. Zonations of rocky shores
A striking characteristic of all rocky shore is vertical zonation according to geographical location, tidal range, exposure to wave action/protected etc. Zonation is largely based on sessile species such as lichens, algae, barnacle’s, mussels etc.

Vertical zonationofrocky shore

• Super littoral Zones
Encrusting black lichens (algae and fungi) (Black Zone) and blue green algae. Certain species, littorina – periwinkles and Large isopods (Ligia) and primitive insects (Machilis)
• Below the super littoral
Periwinkles – Littorina sp- dense 10,000/m², Barnacle Zone – white Zone, Mussel Zone
• Green zone
Attached algae & sessile animals
Adaptation is an alteration or adjustment in structure or habits, often hereditary, by which a species or individual improves its condition in relationship to its environment.