Subarctic volcanic field
Quick facts
Red List habitat type | code RLH5.1c |
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Threat status | |
Europe | Least Concern |
EU | - |
Relation to |
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Source | European Red List habitat factsheet |
European Red List of habitats reports | |
European Red List of habitats (Excel table) |
Summary
The habitat covers sparsely vegetated volcanic areas in subarctic and arctic regions of Europe. It includes active volcanos, recently formed lava streams, and older lava fields and rocks, as well as volcanic slopes and plains with sparse vegetation. It is a relatively broad defined type, but in its distribution it is rather limited to a small part of Northern Europe. The habitat is found on large parts of the central highland of Iceland, almost everywhere where the volcanos and rocks are not covered by glaciers, and also in lowlands. Besides it covers small parts of the Norwegian arctic island Jan Mayen, in places where lava fields have been only sparsely colonized.
The central Icelandic highland has a naturally sparse vegetation cover, due to erosion by wind and rain. Here, on old lava soils, sparsely vegetated fields dominate with stony, gravelly, coarse-sandy, sometimes slightly loamy black soil, with spread pebbles and rocks. These gravel fields are called melar in Icelandic. They are well-drained, nutrient-poor and desiccate quickly due to wind and strong heat on sunny days. The dry conditions in these ‘edaphic deserts’ cause erosion of soil by wind, which prevents development of higher vegetation cover. Only few vascular plants are resistant to the harsh environment, mainly hemicryptophytic species. Examples are Silene acaulis, Armeria maritima, Agrostis vinealis, Cerastium alpinum, Thymus arcticus, Festuca pruinosa (= F. rubra s.l.), Poa glauca and Cardaminopsis petraea. Cryptogams are relatively rare and occur with low cover. Snow cover on wind-exposed fields is low, but in sheltered depressions transitions to snow beds occur, with higher vegetation cover and species of the alliance Salicion herbacea. Where soils are more stabilised lichens and mosses have higher cover and transitions towards heathlands occur. The typical plant community on these gravel fields is the association Armerio-Silenetum acaulis, which is classified in the alliance Veronico-Poion glaucae. This alliance is sometimes placed in the grassland class Koelerio-Corynephoretea, sometimes under the Sedo-Scleranthetea.
Relatively recent lava fields are colonized by lichens only, including species of Stereocaulon (S. denudatum), Pletigera malacea, Cladonia spp (C. mitis, C. rangiformis, C. uncialis, C. coccifera) and Alectoria ochroleuca. Further succession leads to Racomitrium dominated habitats, included under Moss and lichen tundra (F1.2).
Habitat H5.1c is also related to Fjell fields (H5.1a), which is also a sparsely vegetated habitat. This however is a (sub)alpine temperate and boreal mountain habitat, found in most cases on siliceous bedrock (acidic soil). In most Fjell fields lichens and mosses play an important role.
Indicators of good quality:
- Long-term stability of patches with extreme low vegetation cover
- No dominance of mosses
- Low cover of pioneer lichens
Threat status
Synthesis of Red List assessment
EU | |
Red List Category | Red List Criteria |
- | - |
Europe | |
Red List Category | Red List Criteria |
Least Concern | - |
Confidence in the assessment
Pressures and threats
- Climate change
- Changes in abiotic conditions
- No threats or pressures
- No threats or pressures
Habitat restoration potential
Trends in extent |
|
Average current trend in quantity |
|
No occurrence ![]() |
Stable ![]() |
EU28 | EU28+ |
Trends in quality |
|
Average current trend in quality |
|
No occurrence ![]() |
Unknown ![]() |
EU28 | EU28+ |
Conservation and management needs
List of conservation and management needs
- No measures
- No measures needed for the conservation of the habitat/species
Distribution
Geographic occurrence and trends
EU28 | Present or presence uncertain | Current area of habitat (Km2) | Recent trend in quantity (last 50 years) | Recent trend in quality (last 50 years) |
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EU28 + | Present or presence uncertain | Current area of habitat (Km2) | Recent trend in quantity (last 50 years) | Recent trend in quality (last 50 years) |
---|---|---|---|---|
Iceland | Present | unknown | Stable | Stable |
Jan Mayen | Present | unknown | Stable | Stable |
Extent of Occurrence, Area of Occupancy and habitat area
Extent of Occurrence (EOO) (Km2) | Area of Occupancy (AOO) | Current estimated Total Area | Comment | |
---|---|---|---|---|
EU28 | - | - | - | |
EU28+ | 213 | unknown |
EOO = the area (km2) of the envelope around all occurrences of a habitat (calculated by a minimum convex polygon).