Tide pool

Tide pools (CCT) and rock pools ( RP) (so-called Lithotelmen ) represent extreme habitats in Eu - up supralittoral ( Surf to splash zone ) dar. of rocky shores to own both rock pools and tidal pools that they no permanent inflow from the open sea ( have fresh water ).

The tide pools that are in the low to mid intertidal are usually supplied regularly with fresh water at high tide. The rock pools of the upper intertidal to the border between the upper supralittoral and terrestrial zone, however, is only about splashing, water spray of the surf in storm conditions or by precipitation of fresh water.

The location of the rock pools and tidal pools thus shows what a difficult site conditions, the creatures living in it and plants are exposed. While the inhabitants of tide pools for example, must fight against it, to be driven out at high tide on the flow to the open sea, it is important for residents of the Rock Pools, against a progressive dehydration by sun and wind and the associated increase in salinity in the pool to be prepared. This latter problem can not be excluded even in the tide pools. If the danger of complete drying is not so great, but as the temperature is at least rise in tide pools during prolonged sun exposure compared to the significantly in the open sea.

The most important abiotic environmental factors for rock pools and tidal pools are thus:

• Sunlight
• Wind
• Precipitation
• Contact with fresh water

The latter point is dependent on the level of the pool or pools above the sea ( Hum ), as well as its distance to the sea. Precipitation plays an important role, since the fresh water of the rain (Sal 0.5 ‰) rock pools or rock pools can be ausgesüßt. To some extent can the freshwater due to lower density to form a fairly uniform layer of lower salinity over the denser salt water.

In addition to the above-mentioned abiotic factors and biotic factors have a strong influence on the milieu in rock pools and tidal pools. For example, increases the density of living within plants ( algae and autotrophic plankton) through increased photosynthesis the oxygen content (O2). At the same time, the pH value increased, since O2 is obtained on the elimination of the water as carbonic acid ( H2CO3 ) dissolved carbon dioxide (CO2), that is, the water is less acidic. Lower the heterotrophic creatures in tidal pools and rock pools, however, by O2 consumption and CO2 production the pH. The fluctuations of the pH on a daily basis, however, can explain almost exclusively with the increasing during the day in bright sunlight photosynthesis rate.

Since, as already stated above, the life in the rock pools and tidal pools holds many dangers, residents are dependent on specific adaptation mechanisms. These frequently include methods to protect against dryness, such as when there is no more contact with water after desiccation of a tidal pond. The Pferdeaktinie ( Actinia equina ) pulls in such a case its tentacles one, assumes a spherical shape, and may be this way for some time dry, similar to the dwarf beach snail ( Littorina neritoides ), which uses its blood-vessel- rich mantle cavity for respiration, and also their housing closes with an operculum. However, to the inhabitants of the rock pools and tidal pools, certain variations, v. a respect salinity and temperature, hold them down. The greatest tolerance to Salinitätsschwankungen have the larvae and pupae of Aedes mariae of mosquito.