A phyto-ecological investigation of the Mount Albert serpentine plateau

Abstract

Highest Mg/Ca quotients are found in well to moderately well drained soils. Twelve taxa are more or less restricted to serpentine-rich soils. Of these, six are exclusive (Adiantum pedatum var. aleuticum, Polystichum mohrioides, Cheilanthes siliquosa, Arenaria marcescens, Armeria maritima var. labradorica, Lychnis alpina) and six are preferentials (Arenaria humifusa, Arenaria sajanensis, Artemisis campestris var. borealis, Festuca altaica, Rhododendron lapponicum, Salix artica). Most of these taxa occur more frequently in communities dominated by Rhacomitrium languinosum, which are widely distributed in the alpine tundra. Such communities are found principally on moderately well drained soils having a high Mg/Ca quotients and which are subject to intensive frost heaving. Less well drained soils are colonized by Vaccinium uliginosum-Betula glandulosa and by Scirpus caespitosus communities, which themselves contain fewer serpentinicolous plants. On serpentine, the boundary between alpine tundra and krummholz is at a lower altitude than on other substrates of the region. The ecological position of the serpentinicolous plants and the altitudinal distribution of the vegetation show analogies with other boreal serpentine outcrops. -from Authors