|Van Genuchten, Martinus|
Submitted to: Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 7/21/2007
Publication Date: 11/16/2007
Citation: Jimenez, J., Skaggs, T.H., Van Genuchten, M.T., Candela, L. Estimation of recharge from irrigation flows; Analysis of field and laboratory data and modeling.. Meeting Proceedings. Estudios de la Zona No Saturado del Suelo, ZNS'07, Nov 14-16, 2007, Univ of Cordoba, Spain. Vol VIII, p. 101-105 Interpretive Summary: In arid and semi-arid regions, protecting groundwater resources requires knowledge of the quantity and quality of water flowing into (recharge) and out of (extraction) aquifers. Quantifying groundwater recharge in semi-arid regions poses a number of challenges. In regions with substantial irrigated agriculture, irrigation water percolating below the root zone may constitute a significant percentage of the total recharge. In this work, we investigated a procedure for estimating the fraction of irrigation water that passes through the root zone and tested the method using data from the Campo de Cartagena region of Spain. This work should be of interest to researchers who are seeking to understand groundwater recharge in arid and semi-arid climates.
Technical Abstract: This work is aimed at quantifying aquifer recharge due to irrigation in the Campo de Cartagena (SE Spain). A study of recharge was conducted on an experiment plot cropped in lettuce and irrigated with a drip system. The physico-chemical and hydraulic properties of the vadose zone were characterized through laboratory measurements. In the experiment plot, instrumentation (tensiometers, suction cups, TDR) was installed for monitoring soil conditions at different depths. Using HYDRUS-1D, we simulated crop water uptake and flow through the vadose zone. For the cropping period simulated, 76% of the combined irrigation and precipitation water passed below the root zone and contributed to aquifer recharge.