Abstract
The ‘Le Bray’ site, a 28-year old plantation of maritime pine ( Pinus pinaster Ait.) with an understorey of graminae, is part of the European network Euroflux. Carbon dioxide and water vapour fluxes were measured continuously for 2 years above the canopy with an eddy-covariance system. The 2-year accumulated evapotranspiration amounts to 3184±440 MJ m −2 (1331±186 mm of water) compared to 1860 mm rainfall or 6011 MJ m −2 net radiation. The overall gap in the energy balance is 1322 MJ m −2, partly due to the poor estimation of evapotranspiration during rainy periods. The 2-year sum of carbon sequestration is 11.5±0.8 t of carbon per hectare. The 2-year total ecosystem respiration, estimated by adjusting statistically night-time CO 2 fluxes against the soil–litter interface temperature for turbulent nights only, is about 33.6±2.0 t of carbon. A fairly good statistical relationship is found by multiple regression between daily gross primary production (GPP) on the one hand, and direct and diffuse absorbed PAR on the other hand. The water use efficiency (defined as the ratio of GPP to evapotranspiration) is inversely related to air saturation deficit.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
