RIR—Irrigation runoff

This parameter was calculated with the same method used for runoff from rainfall, after transforming into mm of rainfall the quantity of irrigation water derived from outside the basin and distributed weekly over the whole irrigated area from 15 May to 15 September. In calculating the runoff, only the irrigated surfaces within a band of about 200 m from the lake shores were taken into consideration, as it was thought that the water used farther away would all be absorbed by the soil. The size of this parameter was taken as the same for every year of the study, and equivalent to 0.005 m3 × <sup>10</sup>6.
