From 30 September to 2 October 1999 a workshop was held in Gif-sur-Yvette, France, with the central objective to develop a research strategy for the next 3–5 years, aiming at a systematic description of root functioning, rooting depth, and root distribution for modeling root water uptake from local and regional to global scales. The goal was to link more closely the weather prediction and climate and hydrological models with ecological and plant physiological information in order to improve the understanding of the impact that root functioning has on the hydrological cycle at various scales. The major outcome of the workshop was a number of recommendations, detailed at the end of this paper, on root water uptake parameterization and modeling and on collection of root and soil hydraulic data.
aSub-Department Water Resources, Department of Environmental Sciences, Wageningen University, Wageningen, Netherlands.
bPotsdam Institute for Climate Impact Research, Potsdam, Germany.
cCentre for Water Resources Research, Civil Engineering Department, University College, Dublin, Ireland.
dCenter for Stable Isotope Biogeochemistry, Department of Integrative Biology, University of California, Berkeley, Berkeley, California.
eLaboratoire de Meteorologie Dynamique, Université Pierre et Marie Curie, Paris, France.
fCenter for Ocean-Land-Atmosphere Studies, Calverton, Maryland
gDepartment of Botany and Nicholas School of the Environment, Duke University, Durham, North Carolina.
hAlterra Green World Research, Wageningen, Netherlands.
iDepartment of Geography, University of Maryland, College Park, College Park, Maryland.
jMacaulay Land Use Research Institute, Craigiebuckler, Aberdeen, Scotland.
kDepartment of Physical Geography, Macquarie University, North Ryde, New South Wales, Australia.