Biogenic fluxes of carbon dioxide in the old-growth spruce forest in the middle taiga: Results of eddy covariance measurements

Fluxes of carbon dioxide in the old-growth bilberry spruce forest in the European Taiga are measured by the eddy covariance technique. A carbon dioxide sink to the ecosystem was observed from April until September; the maximum net-exchange rate of carbon dioxide was recorded in July. During the cold period of the year from October to March, the biogenic flux of CO2 was directed from the forest canopy to the atmosphere. According to measurements at u* > 0.2, the total annual NEE was 219 g C m–2; the annual values of the ecosystem respiration Reco and the gross photosynthesis Pgross were 483 and 966 g C m–2, respectively. The conclusion is that the old-growth bilberry spruce forest in the middle taiga subzone was the sink of carbon from the atmosphere during the year of observation.