Mediterranean and temperate volcanic field

The habitat includes permanent habitats occurring on the volcanic areas of the Mediterranean and Macaronesian regions, and - very rarely - in temperate parts of Europe. The plant communities of such environments are typically characterized by pioneer, floristically poor and endemic-rich bio-coenoses. Soils are very primitive, eroded and, as such, they reflect with unusual fidelity the chemical composition of the bedrock. The severe ecological conditions hamper the development of soils, and hence the habitat usually looks very stony, with a feeble accumulation of finer particles wherever conditions become slightly better.

Intense solar radiation, remarkable daily temperature variations, long lasting snow-cover, and mechanical disturbances caused by strong winds are usual conditions for this habitat type. Vegetation typically is scattered and discontinuous with very low cover values (<25%), chiefly dominated by few, relic vascular plants. Large areas are completely unvegetated or only occupied by a cryptogamic vegetation. The most frequent vascular plants are Cerastium tomentosum, Anthemis aetnensis, Scleranthus vulcanicus, Rumex aetnensis, Senecio aethnensis, Saponaria sicula, Viola cheirantifolia, Silene nocteolens, and Argyranthemum tenerifae. Bryophytes (e.g. Isopterygium tenerum, Campylopus pilifer, C. introflexus, Calymperes erosum, etc.) and lichens (e.g. Stereocaulon vesuvianum, Xanthoparmelia conspersa, etc.) are widely spread.

These habitats are found on recently deposited volcanic scoriae (tephra), lava flows or orifices in volcanic areas emitting hot gases and vapours of Italy (Tuscany, Sicily, Latium and Campania), and the Canary Islands. At lower altitudes or where ecological conditions are more suitable, they are dynamically connected with the hemicrypto-chamaephytic plant communities dominated by dwarf, thorny, cushion-like species and/or grasses. Furthermore, they may be contiguous to the phanaerophytic communities chiefly dominated by conifers (e.g. Pinus sp. pl., Juniperus sp. pl., etc.). The great phytogeographical and scientific value of these habitats is given by the high number of relic, mostly endemic, taxa. Outside the Mediterranean and Macaronesian region, some marginal (unvegetated) sites are found in the temperate parts of Europe, like in Romania. Subarctic volcanic features on Iceland are considered under habitat H5.1c.

Indicators of quality:

Natural vegetation chiefly occurring in hostile areas not or slightly affected by human activities, as touristic facilities (e.g. skiing areas, etc.). It is generally rather stable, but local surface area variations linked to the volcanic activity may occur.

Indicators of good quality are:

• occurrence of rare, endemic and phyto-geographically significant plants
• no disturbance by hiking, skiing activities, roads, etc.
• contacts with other natural habitats such as cliffs, mountain woodlands, etc.

Synthesis of Red List assessment

Confidence in the assessment

Pressures and threats