Horizon 1 1 17 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES Agricultural Water Management 67-76 Heterogeneous landscape HYDRUS-1D Vadose zone Water table FRANCE 2017 fdi:010069474 ENG Agricultural Water Management 0378-3774 ISI:000397351400008 10.1016/j.agwat.2017.01.006 https://www.documentation.ird.fr/hor/fdi:010069474 https://www.documentation.ird.fr/intranet/publi/2017/05/010069474.pdf 184 Horizon (IRD) The current study aims to evaluate the capabilities of soil water balance modeling to estimate ET for very different conditions of rainfed grapevine water status, within a vineyard landscape that depicts heterogeneities in canopy, soil and water table conditions. We calibrated the HYDRUS-1D model against measurements of the soil moisture profile within seven contrasted sites, we validated HYDRUS-1D sim-ulations against ET estimates derived from eddy covariance (EC) measurements within two contrasted sites, and we analyzed the temporal dynamics of the HYDRUS-1D ET simulations throughout almost two growth cycles for the seven sites. The calibration of HYDRUS-1D was correctly achieved, with a relative RMSE of 20% on average. Validation of HYDRUS-1D simulations against EC measurements was satisfactory, with RMSE values of about 40W m(-2) at the hourly timescale and 0.5 mm d(-1) at the daily timescale. HYDRUS-1D was able to provide consistent time series of ET within the seven contrasted sites and throughout the two growth cycles. We conclude that HYDRUS-1D simulations can be used as an alternative to EC measurements within rainfed vineyards, to alleviate experimental efforts for device cost and maintenance. Further, HYDRUS-1D simulations can be used for characterizing spatial variabili-ties and temporal dynamics, assessing impact of pedological conditions and land use on ET, or validating remote sensing retrievals over regional extents. 072 UR144 Chili