Aquascope Facts
Cliff and rocky beach ecology

Bare belt

The Swedish coastline is a little unusual because it is the weather that effects the water level more than the tides. On a great many coasts, for example Icelands, Norways and Britians, the tidal differences are much greater, 1 m or more - and is therefore of greater importance than variations in wind and air pressure. This is significant for beach living organisms as tidal variations are much more regular than variations in weather.
    When the wind is calm and there is a high pressure over the Swedish coast, many organisms can be left stranded on the beach over a period of several days without being moistened by the tide, where as on windy days with low pressure, they can be kept wet several days in a row. This is presumably why Swedish coastal areas have a pronounced bare belt along the cliffs, which are otherwise normally uncommon globally. Where tidal variations dominate, lengthy and unpredictable periods of low or high water are uncommon and normally only effect a narrow zone of the beach.
Bare belt
Between the zones of black cyanobacteria and the grey lichens higher up - on these wave exposed cliffs - exists a wide bare belt.

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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