Carbon balance and component CO2 fluxes in boreal Scots pine stands
Kolari P. (2010). Carbon balance and component CO2 fluxes in boreal Scots pine stands. https://doi.org/10.14214/df.99
Abstract
This study quantifies and analyses the dynamics of carbon balance and component carbon dioxide (CO2) fluxes in four Southern Finnish Scots pine stands that covered the typical economic rotation time of 80 years. The study was based on direct flux measurements with chambers and eddy covariance (EC), and modelling of component CO2 fluxes. The annual CO2 balance varied from a source of about 400 g C m−2 a−1 at a recently clearcut site to net CO2 uptake of 200–300 g C m−2 a−1 in a middle-aged and a mature stand. A 12-year-old sapling site was at the turning point from source to a sink of CO2. In the middle-aged stand, photosynthetic production was dominated by trees. Under closed pine canopies, ground vegetation accounted for 10–20% of stand photosynthesis whereas at the open sites the proportion and also the absolute photosynthesis of ground vegetation was much higher. The aboveground respiration was dominated by tree foliage which accounted for one third of the ecosystem respiration. Rate of wood respiration was in the order of 10% of total ecosystem respiration. CO2 efflux from the soil dominated the ecosystem respiratory fluxes in all phases of stand development. Instantaneous and delayed responses to the environmental driving factors could predict well within-year variability in photosynthetic production: In the short term and during the growing season photosynthesis follows primarily light while the seasonal variation is more strongly connected to temperature. The temperature relationship of the annual cycle of photosynthesis was found to be almost equal in the southern boreal zone and at the timberline in the northern boreal zone. The respiratory fluxes showed instantaneous and seasonal temperature relationships but they could also be connected to photosynthesis at an annual timescale.
Keywords
modelling;
photosynthesis;
respiration;
chamber;
eddy covariance
Published 5 February 2010
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Available at https://doi.org/10.14214/df.99 | Download PDF
Original articles
Kolari, P., Pumpanen, J., Rannik, Ü., Ilvesniemi, H., Hari, P. & Berninger, F. 2004. Carbon balance of different aged Scots pine forests in Southern Finland. Global Change Biology 10: 1106–1119.
Kolari, P., Lappalainen, H.K., Hänninen, H. & Hari, P.. 2007. Relationship between temperature and the seasonal course of photosynthesis in Scots pine at northern timberline and in southern boreal zone. Tellus B 59: 542–552.
Mäkelä, A., Kolari, P., Karimäki, J., Nikinmaa, E., Perämäki, M. & Hari, P. 2006. Modelling five years of weather-driven variation of GPP in a boreal forest. Agricultural and Forest Meterology 139: 382–398.
Kolari, P., Pumpanen, J., Kulmala, L., Ilvesniemi, H., Nikinmaa, E., Grönholm, T. & Hari, P. 2006. Forest floor vegetation plays an important role in photosynthetic production of boreal forests. Forest Ecology and Management 221: 241–248.
Kolari, P., Kulmala, L., Pumpanen, J., Launiainen, S., Ilvesniemi, H., Hari, P. & Nikinmaa, E. 2009. CO2 exchange and component CO2 fluxes of a boreal Scots pine forest. Boreal Environment Research 14: 761–783.