Variability in temperature dependence of stem CO2 efflux from Norway spruce trees

0494820 - ÚVGZ 2019 RIV GB eng J - Článek v odborném periodiku
Dařenová, Eva - Acosta, Manuel - Pokorný, R. - Pavelka, Marian
Variability in temperature dependence of stem CO2 efflux from Norway spruce trees.
Tree Physiology. Roč. 38, č. 9 (2018), s. 1333-1344. ISSN 0829-318X. E-ISSN 1758-4469
Grant CEP: GA MŠMT(CZ) LO1415; GA MŠMT(CZ) LM2015061
Výzkumná infrastruktura: CzeCOS II - 90061
Institucionální podpora: RVO:86652079
Klíčová slova: Picea abies * Q10 * R10 * stem respiration
Obor OECD: Forestry
Impakt faktor: 3.477, rok: 2018
Způsob publikování: Open access
https://academic.oup.com/treephys/article/38/9/1333/4841722

This study presents results from continuous measurements of stem CO2 efflux carried out for seven experimental seasons (from May to October) in a young Norway spruce forest. The objectives of the study were to determine variability in the response of stem CO2 efflux to stem temperature over the season and to observe differences in the calculated relationship between stem temperature and CO2 efflux based on full growing season data or on data divided into periods according to stem growth rate. Temperature sensitivity of stem CO2 efflux (Q10) calculated for the established periods ranged between 1.61 and 3.46 and varied over the season, with the lowest values occurring in July and August. Q10 calculated using data from the full growing seasons ranged between 2.30 and 2.94 and was often significantly higher than Q10 calculated for the individual periods. Temperature-normalized stem CO2 efflux (R10) determined using Q10 from growing season data was overestimated when the temperature was below 10 °C and underestimated when the temperature was above 10 °C, compared with R10 calculated using Q10 established for the individual periods. The differences in daily mean R10 calculated by these two approaches ranged between -0.9 and 0.2 μmol CO2 m-2 s-1. The results of this study confirm that long periods for determining the temperature dependence of stem CO2 efflux encompass different statuses of the wood (especially in relation to stem growth). This may cause bias in models using this relationship for estimating stem CO2 efflux as a function of temperature.
Trvalý link: http://hdl.handle.net/11104/0287880