Variation in forest gas exchange at landscape to continental scales

Abstract

The European Community project EUROFLUX has established the first network for monitoring and comparing gas exchange of forest ecosystems via eddy covariance techniques at the continental scale, applying both standardized instrumentation and software. The EUROFLUX workshop entitled 'Water Flux Regulation in Forest Stands' reviewed at the start of the project. Our current understanding of water relations and water balances in European forests. Recent studies of transpiration via sapflow monitoring methods were highlighted and the view of water flux regulation that they provide was examined. Studies of sapflow are being carried out at EUROFLUX sites together with above canopy flux measurements in order to characterize function of the tree canopy compartment. Sapflow studies at additional European sites extend the environmental gradients along which water fluxes are being observed, e.g. by including forests of riparian zones and of high elevation. Achieving an understanding of forest gas exchange response and forest acclimation potential along climate gradients, and especially in response to environmental stresses at the extreme of the gradients, is essential for integrating information on fluxes and biogeochemistry at landscape, regional and continental scales.