Living on the rock surface, organisms in the rocky intertidal are fully exposed to the elements. Another type of rocky shore classification is based on two primary divisions, rocky intertidal and rocky subtidal ecosystems. The rocky intertidal ecosystem can be divided into four zones: the splash zone, high intertidal, middle intertidal, and low intertidal Ricketts et al. A rocky shore is an intertidal area of seacoasts where solid rock predominates.
The intertidal or littoral zone maintains a balance between the land and the sea. It provides a home to specially adapted marine plants and animals. Those organisms, in turn, serve as food for many other animals. The intertidal zone also staves off erosion caused by storms. The supralittoral zone, also known as the splash zone, spray zone or the supratidal zone, sometimes also referred to as the white zone, is the area above the spring high tide line, on coastlines and estuaries, that is regularly splashed, but not submerged by ocean water.
It was further concluded that the principal agent responsible for the horizontal distribution of organisms around South Africa is sea temperature ; that for zonation on open rock the controllers of primary importance are degree of exposure to the desiccation-heat-light complex acting together with degree of exposure to …. Example of Zonation Environmental factors, such as temperature, wind exposure, light intensity, wave action, and salinity, vary as we move up and down this area.
Therefore, the intertidal communities create bands that differ in the species that occupy them. The high intertidal zone borders on the splash zone the region above the highest still-tide level, but which receives wave splash.
On shores exposed to heavy wave action, the intertidal zone will be influenced by waves, as the spray from breaking waves will extend the intertidal zone. Along most shores, the intertidal zone can be clearly separated into the following subzones: high tide zone, middle tide zone, and low tide zone. In the intertidal zone the most common organisms are small and most are relatively uncomplicated organisms. Organisms in the intertidal zone are adapted to an environment of harsh extremes. Water is available regularly with the tides but varies from fresh with rain and river flows to highly saline and dry salt with drying between tidal inundations.
The action of waves can dislodge residents in the intertidal zone. Begin typing your search term above and press enter to search. Press ESC to cancel. Skip to content Home Physics What are 5 major abiotic factors in rocky shores?
Ben Davis October 26, What are 5 major abiotic factors in rocky shores? What are 3 examples of abiotic factors? What animals live in the rocky shores? What are the 5 rocky coast zones? High temperatures will increase the affect of drying out. Increases salinity in pools. South facing will have more illumination and warmth, but dries faster; north is cooler, darker and less likely to dry out.
Thus, on a north facing slope community bands will be wider and higher up the shore. Catenella red alga colonises north aspect whilst on south facing ones the lichen, Lichina replaces it. A flatter shore may provide a greater area of substrate for colonising and will not drain as fast as a steeper one. Large amounts of plankton can increase the turbidity, as will detritus and sewage pollution.
This restricts the light reaching the algae on the rocks. The hardness and size of rocks and boulders will influence an organisms ability to attach itself. Soft rocks will be suitable for burrowers, e. Large boulders and rocks give good shelter for animals and the angle of dip of the rock strata may produce more crevices and pools. If stones are too small they will be mobile, moving around in the surf and so prevent any organism from attaching itself to the rock.
Seepage of water from the cliff can dilute the seawater. Few of the organisms on the shore can tolerate salinity changes. Enteromorpha is so tolerant it is a good indicator of freshwater on rocky shores.
Upper shore rockpools are vulnerable to salinity variation as water runs off the cliff. These are the biological factors influencing the community. Algal turf, like Osmundea and Chondrus , will slow down the drainage on the shore and reduce desiccation. Grazing is very important. A high concentration of limpets will reduce the establishment of the normally dominant brown seaweed.
Removal of limpets from a shore, e. Inter-specific competition occurs when niches of different species overlap. Knotted Wrack occupies a similar position in the middle shore to Bladderwrack. The latter survives wave action better than the former, which is found on sheltered shores. Where they both occur competition allows the former to dominate as it lives for many years longer. The fucoid algae have a "whiplash" affect, where water movement causes a sweeping action of the alga across the rock and prevents the attachment of algae spores and the settling of planktonic larvae.
In this way it competes with barnacles. If the later does manage to become established it may push out the wrack. Populations cannot become established unless juvenile forms are available to colonise the rocks.
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