Journal article

Publication year: 2013

Pages: 1043-1059

Journal: Geoscientific Model Development

Volume number: 6

Issue number: 4

ISSN: 1991-959X

Open access status: Gold

DOI Link: https://doi.org/10.5194/gmd-6-1043-2013

Publisher: Copernicus Publications

Abstract: 
The agricultural water footprint addresses the quantification of water consumption in agriculture, whereby three types of water to grow crops are considered, namely green water (consumed rainfall), blue water (irrigation from surface or groundwater) and grey water (water needed to dilute pollutants). By considering site-specific properties when calculating the crop water footprint, this methodology can be used to support decision making in the agricultural sector on local to regional scale. We therefore developed the spatial decision support system SPARE: WATER that allows us to quantify green, blue and grey water footprints on regional scale. SPARE: WATER is programmed in VB.NET, with geographic information system functionality implemented by the MapWinGIS library. Water requirements and water footprints are assessed on a grid basis and can then be aggregated for spatial entities such as political boundaries, catchments or irrigation districts. We assume inefficient irrigation methods rather than optimal conditions to account for irrigation methods with efficiencies other than 100 %. Furthermore, grey water is defined as the water needed to leach out salt from the rooting zone in order to maintain soil quality, an important management task in irrigation agriculture. Apart from a thorough representation of the modelling concept, we provide a proof of concept where we assess the agricultural water footprint of Saudi Arabia. The entire water footprint is 17.0 km(3) yr(-1) for 2008, with a blue water dominance of 86 %. Using SPARE: WATER we are able to delineate regional hot spots as well as crop types with large water footprints, e. g. sesame or dates. Results differ from previous studies of national-scale resolution, underlining the need for regional estimation of crop water footprints.

Harvard Citation style: Multsch, S., Al-Rumaikhani, Y., Frede, H. and Breuer, L. (2013) A Site-sPecific Agricultural water Requirement and footprint Estimator (SPARE: WATER 1.0), Geoscientific Model Development, 6(4), pp. 1043-1059. https://doi.org/10.5194/gmd-6-1043-2013

APA Citation style: Multsch, S., Al-Rumaikhani, Y., Frede, H., & Breuer, L. (2013). A Site-sPecific Agricultural water Requirement and footprint Estimator (SPARE: WATER 1.0). Geoscientific Model Development. 6(4), 1043-1059. https://doi.org/10.5194/gmd-6-1043-2013