Tham khảo luận văn - đề án 'báo cáo lâm nghiệp: "nutrients in the aboveground biomass of substitute tree species stand with respect to thinning – blue spruce (picea pungens engelm.)"', luận văn - báo cáo phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | JOURNAL OF FOREST SCIENCE 54 2008 3 85-91 Nutrients in the aboveground biomass of substitute tree species stand with respect to thinning - blue spruce Picea pungens Engelm. M. Slodicák J. Novák Forestry and Game Management Research Institute Strnady Opocno Research Station Opocno Czech Republic ABSTRACT The present paper is the first contribution from the biomass quantification series which is realized by Forestry and Game Management Research Institute in the Krusné hory Mts. Northern Bohemia . This study is aimed at blue spruce substitute stands. Research was done within the blue spruce experiment Fláje II in the Krusné hory Mts. 800 m above sea level in the spruce forest vegetation zone acidic category . Results showed that the aboveground biomass of the investigated substitute blue spruce stand without thinning amounted to approximately 56 thousand kg of dry matter per ha at the age of 22 years. Wood and bark of branches are the most important parts of the aboveground biomass ca 40 . Needles and stem wood accounted for approximately 26 and 28 and stem bark only for 6 . At the age of 22 years the investigated substitute blue spruce stand accumulated N - 336 kg P - 28 kg K - 138 kg Ca - 159 kg Mg - 28 kg per hectare. Thinning with the consequent removal of aboveground biomass 54 of trees 40 of basal area at the age of 16 years represented a loss of ca thousand kg ha of total biomass which contained 53 kg of N 5 kg of P 22 kg of K 26 kg of Ca and 4 kg of Mg. The removal of biomass in areas previously degraded by acid deposition may result in the deficiency of Ca and Mg because of their low content in forest soil. On the other hand thinning supported the faster growth of trees left after thinning and consequently faster biomass and nutrient accumulation. Keywords aboveground biomass blue spruce Picea pungens Engelm. Krusné hory Mts. thinning substitute stands Forest stands of substitute tree species were established in the Czech Republic on those sites where the
