Fine root status and element contents in three stands of Norway spruce in the Krkonose Mountains.

Fine root distribution was estimated in three spruce stands with different stages of forest decline. At Mumlavská hora, the most damaged site, ca 96% of the living fine roots were found in the 0– 5 cm soil layer. In contrast at both Modrý důl, (low damage) and Alžbětinka, (moderately damaged) 62 and 68% respectively of the living fine roots were in this layer. A higher fine root biomass was found at Modrý důl than Alžbětinka in the deeper soil layers. At all 3 sites in the 0– 5 cm layer the density of living fine root mass exceeds the necromass. However, in the deeper soil layer necromass exceeds biomass by a factor of 2–4 at Modrý důl, ca 3 at Alžbětinka and by more than 8 at Mumlavská hora. In contrast, the lowest fine root regenerative potential was found at the moderately damaged Alžbětinka plot and the highest potential at the Mumlavská hora plot. Calcium:Aluminium ratios in fine roots were similar at all 3 sites. The differences in root distribution are indicative of subsoil acidity, however the Ca:Al ratios do not support this conclusion.