Improving the performance of irrigation systems plays a fundamental role in increasing their efficiency in the aim of reaching a sound use of irrigation water. COPAM has proven its usefulness in the performance evaluation of on-demand irrigation systems; however, in many cases input data, such as the water volumes delivered at hydrants, are not easily available. To support a wider application of COPAM, we tested the possibility of using irrigation volumes estimated by means of space-borne remote sensing. The Sentinel-2 constellation provides high spatial resolution images with a temporal frequency between 2 and 5 days, which is compatible with the input requirements of COPAM. In the present thesis, an irrigation sector in the Capitanata irrigation network (Foggia Province, no.
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6 of district 10) was chosen to assess its performance by using COPAM with volumes estimated from Sentinel-2 data. As an input of COPAM, the upstream discharge was determined after a proper transformation of the estimated irrigation water requirement volumes and the recorded volumes into flowrates. The estimation of the irrigation water requirement volumes was accomplished through the estimation of crop evapotranspiration, ETcrop, and effective precipitation, Pn, by combining crop parameters (Leaf Area Index - LAI, fractional vegetation cover fc and Albedo) derived from Sentinel-2 images and the meteorological data from the atmospheric model ERA5 collected for the whole study period, from June 1st to September 30th, 2019. The study comprised a comparison of the estimated irrigation water volumes and the corresponding recorded volumes. The results showed a good agreement between the estimated and the registered volumes in a large time scale for 10 days and one-month period, while a large difference was observed in a daily time scale. The performance analysis was carried out at the global and hydrant level. The estimated discharge was lower than the registered discharge and it reflected better performance. Last but not least, some recommendations were proposed for improving performance in the critical zones.
