U2-8 - Éboulis riches en bases de la Méditerranée occidentale

Western Mediterranean base-rich scree

Classification des habitats EUNIS 2022

Descriptif de l'habitat

Calcareous and ultrabasic scree, with boulders, rock debris and riverine gravel derived from sedimentary and metamorphic rocks, ultramafics and basic volcanics occurring through the western Mediterranean, from lowlands to the high mountains. Epilithic bryophytes and lichens may be very diverse, particularly in the mountains, where they are mostly found in crevices and other shady and humid microsites of immobile boulders. The vascular plant vegetation comprises hemicryptophytes and chamaephytes adapted to the mechanical disturbance caused by scree movements, shortages in water supply and lack of fine-grained soil. The habitat becomes scarcer and more scattered in the foothills and lowlands and more prone to be affected by human disturbances, such as quarrying and infrastructure development. Nevertheless, high mountain screes are usually well preserved in a very natural state.

Espèces diagnostiques

Galeopsis angustifolia, Ptychotis saxifraga, Erodium daucoides, Rumex scutatus

Espèces constantes

Rumex scutatus, Vincetoxicum hirundinaria, Picris hieracioides, Galeopsis angustifolia, Sedum sediforme, Melica ciliata aggr.

Bibliography

 European Topic Centre on Biological Diversity, 2021. EUNIS terrestrial habitat classification 2021 including crosswalks. ETC/BD-EEA. Table Excel transmise par S. Hennekens (Alterra) le 14/02/2022. (Source)