Fig. 4

Landscape classification of the serpentine soils from the SEP based on their geochemistry. a Three groups of serpentine soils can be considered, top to bottom named as: mountain soils (●), inner ophiolite lowland soils (▲) and north lowland soils (▼). The geographical distribution of each sampling location per cluster can be seen in Fig. 8a, for details within geology, soil and vegetation maps see Additional file 1: Fig. S1. HC considered the total carbon content, the water percentage, pH (Additional file 1: Table S2) and geochemical XRF data (including both majors and traces elements), inset is the distance graph showing the cut point for three clusters. b Three main components explained ~ 69% of the variance within the samples according to PCA: PC1 (37.1%), PC2 (24%) and PC3 (8.05%). The score of each variable within each component is in Additional file 1: Fig. S8