Comparison of four models to calculate canopy resistance of maize in North Italy

This paper examines four models for estimating canopy resistance rc, since it is not a purely physiological term, but it depends also on the prevailing climatic conditions get established over the canopy, in order to calculate the actual evapotranspiration on hourly and daily scales, for maize crop grown in North Italy. A comparison between Measured and estimated eddy covariance data was carried out by analysing in details the four models 1) Monteith, 2) Jarvis, 3) Katerji-Perrier, 4) Todorovic. They are either semi-empirical (1, 2 and 3) or mechanistic (4). Furthermore, the FAO approach was also evaluated and compared with the others techniques.