Alpine Calcareous Scree

In the Alps a number of scree vegetation types have been recognized. On limestone and dolomite scree in the high alpine and nival belts Thlaspi rotundifolium often characterizes the vegetation. Other local dominants may include Achillea atrata, Campanula cochlearifolia, Doronicum grandiflorum, Gymnocarpum robertianum, Leucanthemum atrata, Rumex scutatus and Saxifraga oppositifolia. The many alpine endemics or near endemics found in this type of vegetation include Campanula cespitosa (Campanulaceae), Galium helveticum (Rubiaceae), Papaver alpinum (Papaveraceae), Saxifraga biflora (Saxifragaceae), Valeriana supina (Valerianaceae), Viola cacarata and V. cenisia (Violaceae). Scree vegetation characterized by the alpine endemic Leontodon montanus (Asteraceae) occurs on finer more moist, clay-slate screes with quantities of interstitial fine soil. Associate species include Ranunculus parnassifolius and the alpine endemic Saxifraga biflora subsp. macropetala (Saxifagaceae). On the other hand, some of the limestone screes in the subalpine zone with fine-moist soil are characterized by Petasites paradoxus. Other characteristic species here include Valeriana montana and the alpine endemic Adenostyles glabra var. calcarea (Asteraceae) and Poa cenisia (Poaceae). Finally, on calcareous slate slopes, which are thought to have characteristic in between limestone and silicate screes, the alpine endemic Draba hoppeana (Brassicaceae) is likely to become the most characteristic species. Others include Artemisia genipi, Crepis rhaetica, Draba fladnicensis and the alpine endemic Pedicularis asplenifolia (Orobanchaceae).

Alpine Calcareous Grasslands

Most noteworthy of these alpine grasslands are the blue moorgrass (Sesleria albicans)evergreen sedge (Carex sempervirens) formations which is particularly well represented on limestone rocks of the eastern Alps. This formation provides some of the most spectacular flower shows of the alpine and sub alpine zones. Other characteristic species depending on location include the famous Edelweiss (Leontopodium alpinum) together with Anthyllis alpestris, Carduus defloratus, Carex humilis, Erica herbacea, Helianthemum alpestre, H. grandiflorum, Pedicularis verticillata, Phyteuma obiculare, Polygala chamaebuxus and endemic or near endemic species like Alchemilla hoppeana (Rosaceae), Carex austroalpina (Cyperaceae) and Pedicularis rostrato-capitata (Orobanchaceae). In places where the snow clears early exposing areas to cold winds Sesleria albicans can still survive but a number of the other associates are replaced by cushion forming plants. One of the most characteristic of these is the cushion-sedge (Carex firma). Apparently this species is highly economic with the nutrients of its self-made humus contained within its cushions, and can even re-root into its dead remains. Other cushion plants and low-growing rosette species found under these conditions may include Chamorchis alpina, Crepis kerneri, Gentiana clusii and Saxifraga caesia. Other alpine calcareous grasslands types found in the Alps include rusty sedge (Carex ferruginea) meadows in the outer Alps and the violet fescue (Festuca violacea) pastures of the northern Swiss Alps.

Alpine and Subalpine Calcareous Rock and Boulder Formations

Although lichens and certain bryophytes can colonize bare rock, phanerogams are largely restricted to cracks and crevices. These so-called chasmophytic (crevice dwelling) species include a number of different associations depending on rock type and environmental conditions and typically include a rich variety of endemic taxa. In the Alps Potentilla caulescens is often the main character species of carbonate rock in the true alpine zone. Among its associates are various endemic or near endemic species like Carex mucronata (Cyperaceae), Minuartia rupestris (Caryophyllaceae) and Valeriana saxatilis (Valerianaceae). On the hard limestone of the Swiss Jura the endemic Androsace helvetica (Primulaceae) can also become characteristic with associates such as the endemic Draba ladina (Brassicaceae). Potentilla caulescens can also be a feature of subalpine carbonate rocks. Its associates may include Festuca stenantha and Hieracium humile. Many other chasmophytic formations have been described particularly in the Carpathian Mountains.

References

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