Red List habitat classification > RLD - Mires and bogs > RLD4.2 Arctic-alpine rich fen

Arctic-alpine rich fen

Quick facts

Red List habitat type code RLD4.2
Threat status
Europe Vulnerable
EU Vulnerable
Relation to
Source European Red List habitat factsheet
European Red List of habitats reports
European Red List of habitats (Excel table)


Fens around springs and small rivers in the alpine belt of European mountains (the Alps, Pyrenees, Scandes, Scotland) and in the northernmost (arctic) part of Europe, including Svalbard and Iceland. They are found on open substrates that are constantly flushed by cold and base-rich water. The sites are extreme with respect to soil and microclimate. Cold water is constantly present in the root horizon and restricts ion uptake of plants. Frequent disturbances, a high amount of oxygen in the soil water as well as low productivity due to low temperature during the short vegetation period prevent any remarkable peat accumulation and peat layer is typically lacking or very thin (< 20 cm). If peat accumulation would increase, other fen habitats would develop. Solifluction and cryoturbation lead to disruption of plant roots and soil surface structures.

The vegetation substitutes at high altitudes and latitudes the Caricion davallianae vegetation of type D4.1. The vegetation consists of small sedges, rushes, small herbs and non-sphagnaceous (brown) mosses and includes many arctic-alpine species. Most characteristic are Carex bicolor, Carex microglochin, Carex maritima, C. norvegica, Carex atrofusca, Carex frigida, Carex saxatilis, Carex vaginata, Carex aquatilis ssp. stans, Kobresia simpliciuscula, Scirpus pumilus, Juncus arcticus, Juncus alpinoarticulatus, Juncus castaneus, Juncus triglumis, Juncus biglumis, Saxifraga oppositifolia, Tofieldia pusilla. Vegetation is usually polydominated. Bryophyte layer consist of hepatics (Aneura pinguis) and different brown mosses such as Amblyodon dealbatus, Bryum pseudotriquetrum, Calliergon richardsonii, Campylium stellatum, C. polygamum, Catoscopium nigritum, Cinclidiun stygium, Paludella squarrosa, Philonotis calcarea, P. tomentella, Scorpidium cossonii, S. revolvens (locally), Tayloria lingulata, Tomentypnum nitens and Warnstorfia exannulata. Within these sites appear species that can be treated as glacial relicts in the European mountains or surviving species during the Pleistocene glaciation in the boreal and arctic refugial areas. In high mountains outside the Alps, Pyrenees and Scandes, these habitats are depauperate and transitional to spring and small-sedge fen habitats.

These habitats exist in high-mountain or arctic areas and are threatened by direct human activities: tourism, construction of small power station, construction that cause erosion or snow slide, capture of springs, channelling of streams (water supply) etc. Global changes might change the precipitation and temperature regime and can change dramatically the species composition.

Indicators of good quality:

  • Species richness and presence of diagnostic species
  • Absence of human intervention
  • Permanent water flow
  • Low productivity
  • Presence of mosses 

Characteristic species
For full habitat description, please download the habitat factsheet.

Threat status

Synthesis of Red List assessment

Over the last 50 years the habitat has suffered a loss of area and degradation in quality, but not enough to fit any Red List category. However, a severe decline is expected because of climatic change (based on geographical modelling) which argues for (at least) the Vulnerable (VU) category under criterion A2a. This expected decline is supported by ongoing habitat loss in the Alps by development of ski resorts, nutrient enrichment and glacier retreats. The expected decline of the habitat may become reality quickly, if the metapopulation functioning of key species will collapse due to low connectivity of suitable habitats.
Red List Category Red List Criteria
Vulnerable A2a
Red List Category Red List Criteria
Vulnerable A2a

Confidence in the assessment

Red List of habitat categories and criteria descriptions

Pressures and threats

  • Human intrusions and disturbances
    • Outdoor sports and leisure activities, recreational activities
    • Skiing complex
  • Natural System modifications
    • Human induced changes in hydraulic conditions
    • Water abstractions from groundwater
    • Groundwater abstractions for  public water supply
  • Natural biotic and abiotic processes (without catastrophes)
    • Biocenotic evolution, succession
  • Climate change
    • Temperature changes (e.g. rise of temperature & extremes)
    • Droughts and less precipitations

Habitat restoration potential

Naturally, but only if regional metapopulations of species remain in the vicinity.
Through intervention (removing drainage), when the hydrology is disturbed, but also in this case the characteristic species must survive locally.

Trends in extent

Average current trend in quantity

Decreasing Decreasing
EU28 EU28+

Trends in quality

Average current trend in quality

Decreasing Decreasing
EU28 EU28+

Conservation and management needs

No intervention is needed in most cases. However, some artificial disturbances may be needed if succession towards more productive stands takes place. And restoration of hydrological functioning may be needed for drained fens.

List of conservation and management needs

  • No measures
    • No measures needed for the conservation of the habitat/species
  • Measures related to wetland, freshwater and coastal habitats
    • Restoring/Improving the hydrological regime
  • Measures related to spatial planning
    • Establish protected areas/sites


For each habitat a distribution map was produced from a wide variety of sources indicating known and potential occurrences of the habitat in 10x10 km grids within Europe. Occurrences in grid cells were given in two classes: actual distribution from relatively reliable sources (surveys, expert knowledge), and potential distribution based on models or less reliable indicators. Please download the fact sheet to see the map.

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)
Austria Present 8.8 Decreasing Decreasing
Finland mainland Present 10 Stable Stable
France mainland Present 9 Decreasing Decreasing
Germany Present Unknown Unknown Unknown
Italy mainland Present 12 Decreasing Decreasing
Slovenia Present Unknown Unknown Unknown
United Kingdom Present 0.7 Decreasing Decreasing
Romania Present 0.1 Stable Stable
Sweden Present - -
EU28 + Present or presence uncertain Current area of habitat (Km2) Recent trend in quantity (last 50 years) Recent trend in quality (last 50 years)
Kosovo Present 1.5 Decreasing Decreasing
Switzerland Present 2 Decreasing Decreasing
Norway Mainland Present 750 - Decreasing

Extent of Occurrence, Area of Occupancy and habitat area

Extent of Occurrence (EOO) (Km2) Area of Occupancy (AOO) Current estimated Total Area Comment
EU28 4047750 400 41
EU28+ 435 800
AOO = the area occupied by a habitat measured in number of 10x10 km grid cells.
EOO = the area (km2) of the envelope around all occurrences of a habitat (calculated by a minimum convex polygon).

Characteristic species

Not available

Vegetation types

Relation to vegetation types (syntaxa)

Not available

Other classifications

Not available
European Environment Agency (EEA)
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