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There, the subalpine belt is characterized by widespread conifer forests and related scrubs and grasslands, and gives way upwards to the alpine belt through the treeline ecotone.
From lowlands to the subalpine belt, they form secondary vegetation related to deforestation, or permanent units on rocky slopes, whereas in the alpine belt they mainly inhabit the most balanced habitats (flat areas and gentle slopes).
In most sectors, the decreasing trend was greater in the subalpine belt, and became sharper towards the alpine and the basal belts.
The endemic flora (Figure 7 down) gave also a humped response along the altitudinal gradient, but with respect to the whole flora, the endemics showed a somewhat symmetric pattern, with a moderate increase and sharper decrease along the gradient and with maxima at higher altitudes, well in the subalpine belt. This pattern is clearer for the axial Pyrenees (with a clear maximum at 2,200-2,300 m asl) than for pre-Pyrenees (with maximum at 2,000-2,100 m asl, and submaxima at lower altitudes).
Geophytes, hydrophytes and chamaephytes maintained low representation through most of the gradient, but while geophytes and hydrophytes clearly decreased and eventually disappeared from mid subalpine belt to the summits, chamaephytes increased along the high mountain and reached a high percentage towards the summits (> 30%).
A subalpine belt of predominantly mountain birch merges 100-200 m downslope with coniferous forest of either Scots pine (Pinus sylvestris L.) or Norway spruce (Picea abies (L.) Karst.).
In the subalpine belt, birch forms closed stands that regenerate vegetatively by trunk sprouts.
Luzulo italicae-Nardetum strictae is distributed in the subalpine belt of the calcareous central Apennines, and it is often in contact with Taraxaco apennini-Trifolietum thalii (Biondi & al., 1992, 1999a; Blasi& al., 2005).
This vegetation is distributed on the calcareous massifs of the central-southern Apennines, from the Sibillini to Pollino, mainly in the subalpine belt. It is a primary pasture of high environmental value.
Brachypodium genuense grasslands found in the subalpine belt of the Sibillini mountains (Table 8) grow on calcareous slopes with moderate gradient, in fairly xeric stands, often with a southern exposure, and cover an altitudinal range between 1800 and 2100 m Brachypodium genuense shows high cover values, giving these grasslands a smooth and dense appearance.
The nitrophilous vegetation occurring in the subalpine belt is often correlated with overgrazing.
Carduetum chrysacanthi, described for the subalpine belt of the Laga massif (central Apennines, Pedrotti, 1981, 1982a) and found also in Campo imperatore (Gran Sasso, Biondi & al., 1999a), grows especially in places with a high density of livestock and, therefore with accumulated organic remains.