Scientific publications

The studies of ecosystem fluxes and soil carbon dioxide emissions during the snowless period of the year in a cowberry-lichen pine forest in the Pechora-Ilychsky Nature Reserve are discussed. Measurements of CO2 fluxes between the forest and the atmospheric boundary layer were made by using the eddy-covariance system and CO2 emission from the soil surface was estimated by static chamber method. The seasonal variation of the net exchange of carbon dioxide (NEE) and gross photosynthesis (Pgro ss) corresponded to air temperature and PAR changes, with highest values noted in June and July. There was a significant decrease in NEE due to a decrease in temperature and solar radiation during rainfall. The total net exchange of CO2 in the cowberry-lichen pine forest from April to September was –895 g CO2/m2, and gross photosynthesis corresponded to –2037 g CO2/m2. Ecosystem respiration (Reco) also depended on the air temperature and therefore increased from May to August, and the Reco/Pgross ratio grew from 0.4 to 0.8. The CO2 emission from the soil surface (Rsoil) in the pine forest gradually increased from May to July, but with a downward trend in August. However the soil CO2 flux grew after heavy rains in mid-August. The Rsoil/Reco ratio in the cowberry-lichen pine forest ecosystem varied between 0.5–0.9 with the maximum values in July