The water footprint and virtual water exports of Spanish tomatoes

D. CHICO et al. 29TABLE 4. Proportion of green and blue water footprint (WF) in open-airirrigated systems and average apparent water productivity (WAP) of themain producing provinces under different production systems (€/m 3 )Proportion of WF Proportion WAP of WAP of open-air WAP ofProv. Green WF vs. of Blue WF rainfed irrigaton greenhousesTotal WF vs. Total WF systems (€/m 3 ) systems (€/m 3 ) (€/m 3 )Badajoz 5.9 94.1 3.1 0.03Almería 6.0 94.0 3.9 7.1Murcia 6.8 93.2 3.8 3.9 8.8Las Palmas 4.2 95.8 18.1 4.6 9.3Granada 9.0 91.0 7.3 7.2Cáceres 4.7 95.3 2.2Sevilla 3.1 96.9 2.6 3.1 127.4Navarra 7.4 92.6 3.4 6.3National average 8.7 91.6 2.1 3.1 7.8season of the year. On average, the WAP of tomato was about5 €/m 3 . In the tomato production, the prices vary significantlydepending on the time of the year, being a stimulus for offseasonproductions (autumn and winter) where it is possible.Tables 4 and Table 5 show the apparent productivity of waterover the different production periods of the year and productionsystems for the main producing provinces.As shown in table 4, greenhouse production has muchhigher productivity compared to open air, irrigated. The relativelylow productivity of rainfed production leads to ahigher water footprint of this production system. As shownin Table 5 the productivity of tomatoes in the early and lateseason is much higher than that of the middle season. Inthe Spanish case, these productions correspond mainly togreenhouse production.However, some of the values obtained seemed to be toohigh to be realistic (e.g. apparent water productivity of Sevillaprovince under greenhouses). Apparent water productivityis calculated at market price and in correspondence with