Above ground biomass and nutrient distribution in a limed and fertilized norway spruce ( picea abies) plantation : Part I. Nutrient concentrations

The spatial variation in the concentrations of various plant nutrients in the above ground biomass was examined in a fertilized and limed 59-year-old Norway spruce stand on a nutrient poor soil at Klosterhede, western Denmark. Two types of lime (calcite and dolomite combined with additional kieserite and phosphate) were applied alone and in combination with conventional NPK fertilizer to form five different treatments. Sample trees of different size classes were felled and the nutrient concentrations of N, P, K, Ca, Mg and S were analysed at various heights from ground level, dividing the biomass into seven compartments (stem wood, stem bark, living branches, dead branches, current year needles, older needles and cones). The nutrient concentrations were generally highest in the actively growing parts of the trees (e.g. needles and stem bark). The concentrations of N, P, K and S were generally higher in current year needles than in older needles, whereas the opposite pattern was observed for the concentrations of Mg and Ca. The concentrations of N, P, S and Ca were increased by the treatments, most pronounced in the actively growing parts of the trees. However, the concentrations of K and Mg seemed unaffected by the treatments. When N and P were applied, the concentrations in the current year needles were elevated to levels that could be considered above deficiency in all parts of the canopy. Nutrient concentrations did not vary with tree size.