Carbon budget of a spruce forest ecosystem

TLDR: The Weidenbrunnen site in the Lehstenbach catchment was selected as a EURO-FLUX site (Valentini et al. 2000) and was also used in the following CARBOEUROFLUX program for systematic investigations with respect to the data quality of turbulent fluxes.

Abstract: The investigation of carbon fluxes is of immense interest in ecosystem and climate research. Forest ecosystems may be a sink for anthropogenic carbon, if the assimilation is larger than the respiration. Alternatively, increasing temperatures due to climate change (IPCC 2001) may be a reason for increasing respiratory fluxes. While low-altitude spruce sites in Germany are significant carbon sinks (e.g. Bernhofer et al. 2003), sites above 600 m a.s.l. are only small sinks or may change their character by climate change. Therefore the Weidenbrunnen site in the Lehstenbach catchment was selected as a EUROFLUX site (Valentini et al. 2000) and was also used in the following CARBOEUROFLUX program for systematic investigations with respect to the data quality of turbulent fluxes. Overviews of the European carbon program and of the worldwide FLUXNET program are respectively given by Valentini (2003) and Baldocchi et al. (2001). All relevant references are also provided herein. Furthermore, the site was used for process studies to separate assimilation and respiration fluxes, and to study the exchange conditions between the forest and the atmosphere (Wichura et al., this Vol.). All of these studies were part of the ecosystem research of the Lehstenbach catchment, the main research area of the Bayreuth Institute of Terrestrial Ecosystem Research (BITOK). The main results for the carbon dioxide flux measurements since 1997 are discussed in this chapter.