The expansion of Picea forests led to natural acidification of the lake water causing changes in the diatom assemblages, in particular an increase of acidophilous
taxa such as Eunotia spp.
A second cluster (cluster 2) consists of Fagus, Pteridium aquilinum and Carpinus betulus, representing acidophilous beech forests, while cluster 3 comprises deciduous Quercus and Ostrya/ Carpinus orientalis pollen types as the best representatives of thermophilous beech forests.
In general, samples from acidophilous, ravine and calcicolous beech forests and subalpine calcareous grasslands were placed at the negative side of the axis 1, while samples from pseudomaquis communities and thermophilous beech forests were mostly at the positive part.
The nucleus is difficult to visualize because the cell is filled with vacuoles and granules of yolk characterized by a strongly acidophilous mass (Figure 5).
The germinative zone appears in dispersed points of the gonad and is compressed by the mature acidophilous oocytes (Figure 9).
Although FANELLI (1998) provisionally classified the Dasypyrum villosum associations of the Rome countryside in the Echio-Galactition, he highlighted the possibility of including the Dasypyrum villosum communities in the Vulpio-Lotion, an alliance originally described from the Dalmatian coast (HORVATIC, 1963) to capture the slightly acidophilous therophyte-rich grassland vegetation.
DIAGNOSIS: acidophilous grasslands on siliceous substrates dominated by Nardus stricta, developed in the montane belt of the south central Calabria (Southern Italy).
These are lineal forests usually 12-18 m high, whose undergrowth normally includes not only Erica arborea but also some acidophilous
species frequently recorded in the nearby climatophilous forests (Avenella flexuosa, Blechnum spicant, Dryopteris affinis, Dryopteris dilatata, Euphorbia dulcis, Hedera hibernica, Holcus mollis, Lonicera periclymenum, Luzula henriquesii, Omphalodes nitida, Oxalis acetosella, Polypodium vulgare, Saxifraga spathularis, Stellaria holostea, Teucrium scorodonia, Vaccinium myrtillus or Viola riviniana).
In fact it is very easy to distinguish the acidophilous
and oligotrophic beech woods (Luzulo pedemontanae-Fagetum) from the sub-acidophilous (Gymnocarpio-Fagetum) or neutro-basophilous eutrophic ones woods (Cardamino heptaphyllae-Fagetum) according to floristic, coenological and syntaxonomical aspects.
The distribution of the clusters along axis 1 (Figure 3) appears to follow a soil gradient, from left to right, from basophilous to acidophilous
vegetation types: two main groups of clusters are clearly separated: the Seslerion communities on the left and the Nardion communities on the right.
This association differs from the other acidophilous
The present paper aims at providing a phytosociological and syntaxonomical classification of the acidophilous
pastures of Mount Greco (2285 m a.s.l.), which are pertinent to beech woodlands series of vegetation, pointing out the main physical criteria influencing the spatial distribution of the various communities identified.