Syntaxonomy and community ecology of mires in the Rhaetian Alps (Italy)

Abstract

On the basis of cluster analysis of phytosociological releves, the mire vegetation in the Rhaetian Alps was arranged in sixteen plant communities syntaxonomically in cluded in four classes. The class Potametea was characterised by two different plant communities of perennial hydrophytes rooting in the bottom sediment of lakes (commu nities of Potamogeton alpinus and Potamogeton natans, respectively). The class L i tt 0 re 1letea included two plant communities characteristic of shallow water bodies (Callit richo-Sparganietum and community of Ranunculus reptans). The class Scheuchz erio-Caricetea nigrae included small-sedge swards and quaking rafts spanning a broad range of hydrochemical conditions with 8 plant communities and 5 alliances. The alliance Rhynchosporion albae included the vegetation of hollows and shallow ponds in nutri ent-poor mires, with the Caricetum limosae and a community of Eriophorum angusti fo lium. The alliance Caricion lasiocarpae, including vegetation of hollows and pools in intermediate mires, was represented by an only association, the Caricetum rostra tae. The alliance Caricion nigrae included sedge-swards in acid fens, with the Cari cetum nigrae, the Caricetum pauperculae, the Menyantho-Sphagnetum ter etis and the Eriophoretum scheuchzeri. The alliance Caricion davallianae in cluded rich fen vegetation with an only association, the Drepanoclado-Trichopho return cespitosi. The Caricion atrofusco-saxatilis included only the Caricetum microglochinis, a carbonate fen association in the alpine vegetation belt. The class Oxycocco-Sphagnetea corresponded to the vegetation of Sp hagnum hummocks in ombrogenous mires, with three associations: the Sphagnetum magellanici, the Erio phoro-Trichophoretum cespitosi and the Pinetum rotundatae. The habitat in all plant communities was defined on the basis of pH and electrical conductivity of pore water, reflecting the degree of inflow of geogenous water. The role of elevation in affecting the distribution of plant communities was particularly clear for the associations of the class Oxycocco-Sphagnetea, which were mainly developed in the lower sub-alpine vegetation belt, and for the Eriophoretum scheuchzeri, confined to the alpine vege tation belt.

Diversity of wetland vegetation in the Bulgarian high mountains, main gradients and context-dependence of the pH role

“…In these studies, the vegetation correlated with the mineral richness and pH of groundwater almost in all cases (e.g. Gerdol 1995;Gerdol and Bragazza 2001;Ha´jek 2002). On the contrary, Bulgarian high mountains are specific due to rarity of calcareous bedrock, absence of bog vegetation and shifted optima of calcicolous species.…”

“…European mountains (Alps, Carpathians, Pyrenees) represent a secondary centre of mire and spring distribution and they have been intensively investigated in the last years (e.g. Coldea 1997;Bragazza and Gerdol 1999a;Gerdol and Bragazza 2001;Molina 2001;Ha´jek et al 2002). Despite the fact that Bulgarian mountains are comparable rich in mire vegetation as other European mountains there is an extreme scarcity of vegetation data from Bulgarian mires.…”

Conservation priority of Italian Alpine habitats: a floristic approach based on potential distribution of vascular plant species

“…Indeed, a comparison of historical peatland distribution with current situation demonstrates as nearly all of the peatlands located in lowlands have disappeared (Provasi 1943;Giacomini 1946;Moretti and Balboni 1966) so that, at the present, the best preserved peatlands can be found above 1,000 m a.s.l. where the pressure of changing land use has been lower than in lowlands (Gerdol and Tomaselli 1997;Miserere et al 1998;Gerdol and Bragazza 2001).…”

Mire vegetation of the Muránska Planina Mts — formalised classification, ecology, main environmental gradient and influence of geographical position

“…Within mire vegetation, this mineral richness gradient (often called poor-rich gradient) was described from various areas in Europe (e.g. Gerdol 1995;Bragazza & Gerdol 1999;Gerdol & Bragazza 2001;Tahvanainen 2004;Hájek et al 2006;Navrátilová et al 2006). In addition to water pH and conductivity, some other ecological variables (water calcium and magnesium concentrations as well as soil carbon content) showed the strongest correlation with the rich-topoor vegetation gradient within spring fen vegetation of the Western Carpathian flysch zone .…”