From the early 1960's there has been a process of urbanization which increased the population with a settlement system
characterized by intensive urban sprawl. As a results, within the GRA urban expansion has left large patches of non-urbanized green and vacant areas. UA occurs mainly within these areas, nowadays organized in a system of parks
which extend close to the city centre, providing multiple ecosystem services and public goods.
Data sources
The estimation of the irrigation water demand and of the amount of water potentially harvested by roofs for each RG was realized by using the following dataset:
geodatabase containing RGs polygons and land use attributes;
average crop coefficients for each RG based on the land use class associated;
climate data of the study area (precipitation and evapotranspiration).
where kc is the average crop coefficient defined according to the land use pattern of each parcel, ETo(i) and Peff(i)
are the reference evapotranspiration and the effective rainfall of the i-th month, both in mm. The product kc by ETo is
the crop water requirement under standard conditions (Allen et al. 1998).
The parameter Peff (i.e. net of foliage interception) can be calculated for each month as (Brower et al. 1986):