Early development and nutrition of Norway spruce (Picea abies(L.) Karst.) seedlings on different seedbeds in the Bavarian limestone Alps – a bioassay

The development and nutrition of Norway spruce seedlings growing under controlled conditions in three different seedbed types (mineral Ah horizon, organic layer, highly decayed dead wood) obtained from two protective forest sites in the Bavarian limestone Alps was investigated for one growing season. The seedlings showed clear responses to the three natural seedbed types in biomass development and nutritional status. Their biomass was significantly lower in mineral soils and organic layers as compared to decayed dead wood. Seedlings in organic and in decayed wood substrates had significantly higher contents of N, P, K, Mn, Zn (only decayed wood), and more balanced nutrient relations as compared to seedlings grown in mineral soils. It was indicated that the acid organic layers and highly decayed dead wood represents a good seedbed for spruce natural regeneration, especially in regard to the impaired nutrient availability on alkaline dolomite sites in the Bavarian limestone Alps.