62.3 - Pavements, rock slabs, moss and lichen carpets

Classification des habitats du Paléarctique (2001)

Description

More or less level surfaces of rock of lowlands, hills and mountains of nondesert regions of the Palaearctic exposed by glacial erosion, by weathering processes, or by nondesert aeolian scouring, bare or colonized by mosses, algae or lichens. The hard rock surface may be apparent or partially or completely covered by indigenous erosional rock debris, in particular, those produced by frost weathering, heaving, thrusting or cracking. Included are, in particular, lapi‚s, karren, limestone pavements of karst landscapes, rock dome tops, whaleback, roche moutonn‚e, flyggberg and rock basin formations of periglacial areas, frost-shattered mountain-top detritus, golec and felsenmeer formations, level surfaces of dykes and old lava flows. Vascular plant communities may colonize cracks and superficially decomposed areas, in particular, Sedo-Scleranthion, Alysso-Sedion albi or Sedo albi-Veronicion dillenii communities of units 34.11 and 36.2, occasionally scree communities of unit 61 or chasmophyte communities of units 62.1 or 62.2. More developed communities belonging to other units may also be present.

Bibliography

Devillers P., Devillers-Terschuren J. & Vander Linden C., 2001. PHYSIS Palaearctic Habitat Classification Database. Updated to 10 December 2001. Institut Royal des Sciences Naturelles, Bruxelles. (Source)

Pearsall, 1971: 80-85; Whitten and Brooks, 1972: 255, 261; Whittow, 1984: 158-159, 302, 389-390, 458-459, 551; Summerfield, 1991: 146, 148-150, 239-240, 273-275, 297; Einarsson, 1994; Gudmundsson and Kjartansson, 1996; Schroeder, 1998: 379-380.