This work aimed at studying water reservoir functioning
of beech trees under climatic and edaphic constraints in a
37-year-old beech stand located in north-eastern France. We
took advantage of the severe climatic conditions during summer
2003 to characterise the impact of soil drought on water
fluxes at the tree and the forest scales and to estimate the
contribution of exchangeable water in reservoirs to total tree
transpiration, under non-limiting soil water or soil drought
conditions.