Diversity and ecology of oak forests in SW Poland (Sudetes Mts.)
This paper presents a typology of oak forest communities in SW Poland. Numerical classification and ordination methods were applied to distinguish the main vegetation units and to identify the environmental gradients affecting their composition. The ecological preferences of the studied communities were analysed using both measured variables and Ellenberg indicator values combined with a modified permutation test. Six vegetation units were distinguished: the association Viscario vulgaris-Quercetum petraeae mainly occurs on shallow, skeletal soils on nutrient-poor substrates in dry habitats, the association Luzulo luzuloidis-Quercetum petraeae in oligotrophic, dry-mesic habitats on moderately steep slopes and plateaux, the association Calamagrostio arundinaceae-Quercetum petraeae in mesic, oligo- and mesotrophic habitats on gentle slopes and plateaux, the community Galium verum-Quercus petraea on ultrabasic substrates of serpentine monadnocks, the association Sorbo torminalis-Quercetum in dry-mesic, mesotrophic habitats on steep, sunny slopes with initial, but relatively mineral-rich soils, and the association Melico pictae-Quercetum roboris in mesic, mesotrophic habitats with deep soils and mineral-rich substrates on gentle slopes and plateaux. The species composition of the syntaxa identified here is mainly influenced by the type of bedrock (particularly its base-richness), soil reaction and nutrients. If there are no differences in base-richness, the second most important factors are those associated with land relief (especially slope inclination) affecting light availability and moisture.