VARIATION IN FOREST GAS-EXCHANGE AT LANDSCAPE TO CONTINENTAL SCALES

The European Community project EUROFLUX has established the first netw ork for monitoring and comparing gas exchange of forest ecosystems via eddy covariance techniques at the continental scale, applying both st andardized instrumentation and software. The EUROFLUX workshop entitle d 'Water Flux Regulation in Forest Stands' reviewed at the start of th e project our current understanding of water relations and water balan ces in European forests. Recent studies of transpiration via sapflow m onitoring methods were highlighted and the view of water flux regulati on that they provide was examined. Studies of sapflow are being carrie d out at EUROFLUX sites together with above canopy flux measurements i n order to characterize function of the tree canopy compartment. Sapfl ow studies at additional European sites extend the environmental gradi ents along which water fluxes are being observed, e.g. by including fo rests of riparian zones and of high elevation. Achieving an understand ing of forest gas exchange response and forest acclimation potential a long climate gradients, and especially in response to environmental st resses at the extreme of the gradients, is essential for integrating i nformation on fluxes and biogeochemistry at landscape, regional and co ntinental scales. ((C) Inra/Elsevier, Paris.).