Table 1 Coordinates, bedrock, topographic features, biogeographic region, and number of sampling units per each chronosequence stage of the four study sites located in Italy

Coordinates

40°14′05.9"N, 8°42′08.8"E

45°06′25.2"N, 7°26′32.9"E

44°35′14.0"N, 7°05′39.2"E

45°46′51.5"N, 7°54′02.7"E

Bedrock

Basalt

Serpentinite

Serpentinite

Gneiss

Elevation (m a.s.l.)

670

480

1380

1760

Slope angle (degree)

5

21.2

26.3

18.6

Altitudinal zonation

Colline

Colline

Subalpine

Alpine

Biogeographic region

Mediterranean

Continental

Alpine

Alpine

below the tree line

above the tree line

Chronosequence stage

Number of sampling units

1

9

3

3

3

2

9

6

6

6

3

9

3

3

0