2. Données et outils
  3. Rechercher un habitat
  4. MA5-51 - Biocénose des sables du supralittoral en Méditerranée
  5. Description
MA5-51 - Biocénose des sables du supralittoral en Méditerranée

Biocenosis of Mediterranean supralittoral sands

MA5-52 - Biocénose des sables du médiolittoral en Méditerranée

Classification des habitats EUNIS 2022

Descriptif de l'habitat

Area corresponding to the upper beach which is only humected by the sea during storms; however, certain areas do escape being totally submerged and receive a large amount of spray coming from the surge of the waves further down. 2 sets of phenomena are responsible for the dampness: at surface level, the dampness is caused by the salty spray from the breaking of the waves on the coast which is the main cause of the saltiness of the sand and the dampness of the night air. This humification only affects the top 2 or 3 centimetres and disappears quickly under the action of the sun; at depth, the sand is damp because of the proximity of the fairly unsalty ground water. The temperature is very variable and the daily differences in temperature may be extremely great: 0 to 20° in the winter, 50° in the summer. These temperatures can be lethal for individuals living in the sand.
The exogenous contribution of organic matter (wracks) is linked to the nature of what is washed up by the sea during storms or comes from the land. It is variable in time and space: tree trunks, bits of wood, detritic material which make up the wracks, algae, phanerogams, anthropic vegetable debris, dead marine organisms, aeolian-origin elements (leaves, insects), and foam from waves made up of “shaped or unshaped elements” of wind-borne marine plankton. To this can be added a fairly considerable quantity of biodegradable or non-biodegradable human-origin rubbish linked to the sea or to the direct waste from tourists frequenting the upper beach.
The physiognomy of the upper beach ranges from shifting sand on compact sand to the presence of fairly damp saline patches on coarse sand. The sea wracks contain floating objects basically washed up during storms and are of two major kinds: chips of wood and fairly well-shaped elements stuck in the sand and tree trunks and sizeable rubbish.
The sedimentary granulometry is relatively variable according to what fine elements have been added. The sediment is thus fairly compact. One can also notice a variability according to the quantity and quality of organic additions (sea foreshores), according to the direction and level of protection of the upper beach considered, and the degree of humectation, different facies can be observed (See facies and associations).

Bibliographie

European Topic Centre on Biological Diversity 2022. EUNIS marine habitat classification 2022 including crosswalks. Table Excel. (Source)