Nutrient content in biomass of bilberry (Vaccinium myrtillus L.) in different habitats of protected areas of Inner Western Carpathians

The primary objective of this paper was to compare the nutrient content (N, Ca, S, K, P, Mg) of bilberry biomass, both aboveground and underground, growing in different habitats along the altitudinal gradient. The research was conducted in protected areas of the High Tatras National Park (Slovakia). Two different habitats subjected to study, namely spruce forest stands affected by disturbances (D - disturbed forest stands) and stands unaffected by disturbances (U - undisturbed forest stands), were located at different altitudes: 1 100 m a.s.l., 1 250 m a.s.l., and 1 400 m a.s.l. We found significant differences in the soil nutrient content along the altitudinal gradient. The highest content of nutrients was detected mostly at the highest altitudes in both habitats. The minimum reached 0.01 g.kg-1 (phosphorus), while the maximum was 8.33 g.kg-1 (nitrogen). In the case of the bilberry biomass, we found statistically non-significant differences in the content of nutrients among the altitudes within both habitats (D vs. U). The principal component analysis (PCA) showed that the aboveground biomass of bilberry had a significantly higher nutrient content compared to the underground biomass. Nutrient content in aboveground and underground biomass ranged from 1.00 g.kg-1 (phosphorus) to 13.49 g.kg-1 (nitrogen) and from 0.38 g.kg-1 (magnesium) to 7.55 g.kg-1 (nitrogen), respectively. The biological absorption coefficient (element content in dry biomass/element content in soil) reached the highest values mostly at the lowest altitude for both aboveground and underground biomass.