Comparison of nutrient and carbon stocks in the aboveground biomass of mature silver fir (Abies alba Mill.) and Norway spruce (Picea abies L. Karst) stands

Prag

2008

334-347

e-journal

200210994

The aim of the study was to compare the stock of essential nutrients and carbon in the aboveground biomass of mature stands of silver fir and Norway spruce. A comparison was carried out for 14 mixed stands of spruce and fir. The tree-level dendrometric characteristics were taken from experimental measurements or were generated using the SIBYLA growth simulator. The amount of biomass was calculated using allometric equations. Samples of stem wood, stem bark, and needles were taken and analysed for carbon, nitrogen, calcium, magnesium, potassium, phosphorus, and sulphur concentrations. Using biomass data, the concentrations of the elements were converted into the stock at the stand level. Overall, spruce fixes a greater amount of carbon. The difference is in the carbon allocation, where fir allocates more carbon in the crown and spruce in the stem. Fir needles contain a greater amount of nutrients than spruce needles. A higher supply of phosphorus, nitrogen, and especially potassium was found in the stem wood and bark of fir, the amount of which is more than twice that of spruce. The stem wood of spruce, on the other hand, fixes more calcium and magnesium. As part of the study, linear regression models predicting the stock of nutrients and carbon depending on the stand basal area were parameterised.
Keywords: allometric models; needle biomass; nutrient content; stem bark biomass; stem wood biomass