Respiratory fluxes in a Canary Islands pine forest.
We estimated component and whole-ecosystem CO(2) efflux (R(ECO)) in a Pinus canariensis Chr. Sm. ex DC stand in Tenerife, Canary Islands, an ecotone with strong seasonal changes in soil water availability. From November 2006 to February 2008, we measured foliage, stem and soil CO(2) efflux by chamber techniques. Site-specific CO(2) efflux models obtained from these chamber measurements were then combined with half-hourly measurements of canopy, stem and soil temperature as well as soil water potential, leaf and stem surface area data for scaling up component-specific CO(2) efflux to R(ECO). Integrated over an entire year, R(ECO) was 938 g of C m(-2) in 2007 and comprised the following component fluxes: 77% from soil, 11% from stems and 12% from foliage. Whole-ecosystem CO(2) efflux varied markedly throughout the year. During the cold and wet season, R(ECO) generally followed the seasonal trends in temperature, and during the warm and dry summer, however, R(ECO) was significantly reduced because of limited soil water availability in the main rooting horizon.
Wieser
Gerhard
G
Department of Alpine Timberline Ecophysiology, Federal Research and Trainings Centre for Forests, Natural Hazards and Landscape, Rennweg 1, A-6020 Innsbruck, Austria. gerhard.wieser@uibk.ac.at
Gruber
Andreas
A
Bahn
Michael
M
Catalá
Enrique
E
Carrillo
Estefanía
E
Jiménez
Maria Soledad
MS
Morales
Domingo
D