CARBON STOCKS OF COARSE WOODY DEBRIS IN FOREST ECOSYSTEMS OF THE LYALSKY TEST SITE (MIDDLE TAIGA, KOMI REPUBLIC)

Abstract

Coarse woody debris (CWD) are important component of forest ecosystems, which must be taken into carbon cycle and ecosystem services determination. The purpose of this work is to assess the carbon reserves and its distribution among components in the CWD of forest ecosystems in the Lyalsky test site. The study was carried out on 29 permanent sample plots established in various types of stands inside the boundaries of the test site. The CWD mass was measured using basal density data, taking into account the stage of decomposition by volume of dead wood, which was then converted to the carbon stock using a factor of 0.47. The carbon reserves of CWD varied in a wide range with mean values in forest stands with a predominance of spruce 5.90±0.99 (CV=67%) t/ha, pine – 2.57±0.42 (CV=49%) t/ha, small-leaved species – 3.72±1.23 (CV=66%) t/ha. Standing dead trees formed more than 50% of CWD, mean share of downed woody debris was 10–26%, and stumps – 4– 8%. The contribution of tree species to the CWD is shown, which depended on the dominated specie forming the tree layer of the studying stand. However, in ecosystems on automorphic soils, the participation of accompanying tree species in the carbon mass of CWD increased. Conversion coefficients were proposed for estimating the carbon stock in CWD based on the volume of wood in the forest stand, which averaged 0.02–0.04 t/m3 with higher values in communities with a predominance of spruce. The data obtained will be used in regional assessing the carbon cycle of forest ecosystems.

Keywords

• coarse woody debris
• spruce forests
• pine forests
• birch forests
• aspen forests
• conversion coefficient