D4Niveau 2Bas-marais riches en bases et tourbières des sources calcaires
↑ Niveau supérieur Description
Peatlands, flushes and vegetated springs with calcareous or eutrophic ground water, within river valleys, alluvial plains, or on hillsides. As in poor fens, the water level is at or near the surface of the substratum and peat formation depends on a permanently high watertable. Excluded are reedbeds (C3, D5).
Taxons associés
Aucun taxon référencé.
D4.1Niveau 3Bas-marais riches en bases, y compris les bas-marais eutrophes à hautes herbes, suintements et ruissellements calcaires
Habitat sélectionné Description
Wetlands and spring-mires, seasonally or permanently waterlogged, with a soligenous or topogenous base-rich, often calcareous water supply. Peat formation, when it occurs, depends on a permanently high watertable. Rich fens may be dominated by small or larger graminoids (Carex spp., Eleocharis spp., Juncus spp., Molinia caerulea, Phragmites australis, Schoenus spp., Sesleria spp.) or tall herbs (e.g. Eupatorium cannabinum). Where the water is base-rich but nutrient-poor, small sedges usually dominate the mire vegetation, together with a "brown moss" carpet. Hard-water spring mires (D4.1N) often contain tufa cones and other tufa deposits. Excluded is the water body of hard-water springs (C2.1); calcareous flushes of the alpine zone are a separate category (D4.2). Rich fens are exceptionally endowed with spectacular, specialised, strictly restricted species. They are among the habitats that have undergone the most serious decline. They are essentially extinct in several regions and gravely endangered in much of central and western Europe.
Taxons associés
Artemisia sp.Esp. diagn.Arthrocnemum sp.Esp. diagn.Corallinaceae sp.Esp. diagn.Corallinaceae sp.Esp. caract.Corallinaceae sp.Esp. diagn.Corallinaceae sp.Esp. caract.Crisiidae sp.Esp. caract.Didemnidae sp.Esp. caract.Eleocharis sp.Esp. caract.Elymus sp.Esp. diagn.Halocnemum sp.Esp. caract.Lotus sp.Esp. diagn.Phragmites australis (Cav.) Trin. ex Steud., 1840Esp. caract.Schoenus L., 1753Esp. caract.Spergularia sp.Esp. diagn.Tofieldia calyculata (L.) Wahlenb., 1812Esp. diagn.Trifolium sp.Esp. diagn.Zygophyllum sp.Esp. diagn.