Calorific Value of Basic Fractions of Above-Ground Biomass for Scots Pine

In this work, the calorific value content in the dry matter of the Scots pine (Pinus sylvestris L.) trees was evaluated. This dry matter was obtained only from the above-ground fractions of its biomass. Our experimental material was taken from five Scots pine trees situated in Slovakia. Wood and bark samples were obtained from the discs which were cut off from three locations, namely from the stem, branches of tree crowns and needles. Then, calorific value capacity (J g⁻¹) in the dry matter of each sample was determined. The impact of statistically significant factors on the calorific value capacity was determined by means of analysis of variance. The average values are, according to the fractions, approximately in the range of 20,000–22,200 J g⁻¹. The smallest capacity of the calorific value, approximately 20,000 J g⁻¹, has the dry matter from bark obtained from the middle and crown parts of the stem. Then, the dry matter from stem wood and branches follows with a value of approximately 20,700 J g⁻¹. Then follows dry matter of the coarse bark occurring on the stem butt and twigs that are covered with needles with a value of about 21,900 J g⁻¹; and finally pine needles with the highest values of about 22,200 J g⁻¹. The calorific value variability is relatively low with coefficients of variations of 0.9–2.8%.