The water footprint and virtual water exports of Spanish tomatoes

More documents

Recommendations

Info

$- \ v - Real Academia de Ciencias Exactas, FÃƒÂsicas y Naturales$

D. CHICO et al. 11otranspiration has been estimated using the CROPWATmodel (FAO, 1998; FAO, 2009a). Within this model, the ‘irrigationschedule option’ was applied, which includes a dynamicsoil water balance and keeps track of the soil moisturecontent over time. The calculations have been done usingclimate data from representative meteorological stations locatedin the major crop-producing provinces, selected dependingon data availability. Monthly reference evapotranspiration(ET o) and precipitation for each of the provinceswas obtained from the National Meteorological Agency(AEMET, 2010). When data were missing, it was completedwith the Integral Service Farmer Advice (MARM 2010a).The total crop area and production for each province wereobtained from the Agricultural and Statistics Yearbook foreach of the studied years, distinguishing growing systemsand growing periods (MARM, 2010b). In the case of the year2008, since data on seasonal production was not available,the same distribution as in 2007 was used. Data on plantingdates and growing length was taken from the “sowing andharvesting calendar” from the Ministry of the Environmentand Rural and Marine Affairs of Spain (MARM, 2002). Thisdatabase includes open-air and greenhouse production.However, when the data was markedly biased towardsshort growing length, or was missing, the data was adjustedfrom that of the nearest, agronomically similar province(Appendix I).Crop parameters required for the evapotraspiration calculationwere based on FAO (1998), adjusted when more localinformation was found (Campillo, 2007) (Table 1).Data on soil types was taken from the EUROSTAT soilmap (CEC, 1985) at 1:1,000,000 scale. Textural classes wereused to determine the soil characteristics and were classifiedin four categories: Sandy-Loam, Loam, Clay-Loam andClay. Canary Islands’ textural classes are based on the Dig-
12 THE WATER FOOTPRINT OF TOMATO PRODUCTIONTABLE 1. Crop parameters used for the estimation of the tomatoevapotranspiration in SpainInitialMiddle FinalDevelopmentStage stage stageKc 0.6 1.25 0.8Root depth (m) 0.1 0.5Critical Depletion 0.3Crop height2 mSource: FAO (1998), Nuez (1995).ital Soil Map of the World (FAO-UN, 2007) at 1:5,000,000scale. For each province the most frequent soil texture wasapplied, which was obtained by overlaying the map of irrigatedareas and the soil texture map (Figure 2). The mapof irrigated areas was taken from the GIS service of theMinistry of Environment and Rural and Marine Affairs ofSpain (MARM, 2010c), which was contrasted with the maintomato producing regions in each province (Hoyos, 2005;Maroto, 2002; Nuez, 1995).In the case of irrigated production, crop blue water use(mm) was obtained selecting the “irrigate at fixed intervalper stage” and “refill soil to field capacity”options in theCROPWAT model considering thus an irrigation scheme thatcompletely satisfies the crop water demand. The actual evapotraspiration(Et a) during the entire growing period is partlyfulfilled by the rain and partly by irrigation. The blue waterevapotranspiration (ET blue) is equal to the ‘total net irrigation’as specified in the model. The green water evapotranspiration(ET green) of the crop is equal to the difference betweenthe total actual evapotraspiration and the net irrigation.ET ( irr= 1)= Total net irrigationblueE [2]ET ( irr= 1) = ET ( irr= i) − ET ( irr=1)greenablue
Page 1 and 2: Papeles de Agua VirtualThe water fo
Page 3 and 4: Papeles de Agua Virtual. Observator
Page 5 and 6: 4 THE WATER FOOTPRINT OF TOMATO PRO
Page 11: 10 THE WATER FOOTPRINT OF TOMATO PR
Page 15 and 16: 14 THE WATER FOOTPRINT OF TOMATO PR
Page 19: 18 THE WATER FOOTPRINT OF TOMATO PR

The water footprint and virtual water exports of Spanish tomatoes

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?