Aquascope Facts
Cliff and rocky beach ecology In brackish areas, many of the most noticable and well known Marine specie are missing. This is true of, for example, large brown algae and many encrusting algae, aswell as lobsters, common crabs, starfish and green sea-urchins. Quite often, whole groups of organisms became scarce when the salt content decreases. Red algae and echinoderms are examples of groups that have very few representatives in brackish water. Green algae and molluscs fare better. Where the salt content is more stable, organisms tend to be more numerous, for example mosses and insects that you normally by lakes and rivers.

Geography, climate and history


Usually, different conditions prevail in different geographical areas and their history can vary greatly. These differences can be of significance for which organisms that are found on different beaches. The climate changes from both east to west and from north to south, thus giving varying light, rain, temperature and ice conditions. Food resources and seasonal changes are also different. An example of geographical differences in a west-east direction is the Norwegian west coast that is open to the deep and extensive North Atlantic, while the Baltic that is almost totally enclosed has a minimal and sporadic exchange with the Atlantic. This affects the water quality and how organisms spread to different areas and establish themselves.
    Another difference between east and west is that during the last 15 000 years the environment has varied much more along the Norwegian and Swedish west coasts. During this period, the Baltic had an opening to the Atlantic, while at other times being totally enclosed.

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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