Aquascope   Facts
Cliff and rocky beach ecology It appears that zoning is most noticable where the living conditions change greatly over a short vertical distance and where the cliffs are smooth and even and not broken by many small environments like cracks, cavities and overhangs. Coincidence also plays an important roll. Certain summers with for example, long periods of low water, certain otherwise prominent organisms, die.
   Here are a few examples of how organisms can be distributed on cliffs and rocky beaches:
Those terrestials organisms that reach the furthest down are certain lichens (e.g. wall lichen and orange lichen ), then there is a bare belt above Marine organisms, salt lichen , green algae(e.g. sea-lettuce), northern rock barnacle, knotted, bladder and toothed wrack . These three specie of seaweed house a large variety of organisms. This is especially true of bladder and toothed wrack from the late summer until the beginning of winter. There are several thread-like algae that use seaweed as a substrate upon which to live. Two examples are Ceramium rubrum and Sphacelaria cirrosa, as shown in the picture below. Many creatures gladly attach themselves to seaweed, which is true of e.g. several specie of hydroids and sea mats.
Oakweed with a growth of red and brown tufts. Ceramium rubrum grows on several different algae, but even directly on rocks and cliffs. To the contrary, it is almost only on oakweed that the brown algae Sphacelaria cirrosa is found. The largest tufts are about 5 cm across.

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Cliffs and rocks are fantastic!
Zoning and flecked occurrence
Animals that are attached
Modular construction
Variation and change
Variations in water level
Wave exposure
Both cliffs and rocks
Freshwater and saltwater
Geography, climate and history
Organisms life cycles
Organisms effect on each other
Energy and the flow of material

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Bo Johannesson Martin Larsvik | Lars-Ove Loo | Helena Samuelsson