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Chufa (Cyperus esculentus L. var. sativus Boeck.) is a traditional crop in the Mediterranean region of Spain, where it is only furrow irrigated. This article analyzes the irrigation performance for this crop, conducting field studies over three consecutive seasons in Valencia (Spain). Irrigation schedule was based on the volumetric soil water content, which was measured with capacitance sensors. Infiltrability was measured with blocked-furrow infiltrometers. An area velocity flow module measured the water flow, the cross-sectional geometry of furrows was determined using furrow profilometers, and times for advance and recession were recorded. WinSRFR software was used to analyze every irrigation event, determining the application efficiency (AE) and distribution uniformity of the minimum (DUmin), and to optimize the combination of furrow inflow (q) and cut-off time (Tco). Average values obtained for AE were 30.1%, 25.6%, and 26.7% in 2007, 2008, and 2009, respectively, and the corresponding DUmin values were 0.54, 0.61, and 0.67. Optimized results showed that it is possible to reach AE and DUmin values up to 87% and 0.86, respectively. However, understanding the q-Tco relationship that maximizes both AE and DUmin is more important than knowing the specific values. A function that related q and Tco was obtained for the typical plot dimensions, and this was validated in 2011. Therefore, this function can be used in most of the plots in the cultivation area., La chufa (Cyperus esculentus L. var. sativus Boeck.) es el cultivo hortícola más representativo de L’Horta Nord de Valencia (España). En este artículo se analiza el comportamiento del riego tradicional (por surcos) en el cultivo de la chufa, realizándose pruebas de campo en tres campañas sucesivas en Valencia. El plan de riego se basó en el contenido volumétrico de agua del suelo, medido con sensores de capacitancia. La infiltrabilidad se determinó mediante infiltrómetros de surco cerrado. El caudal se midió con un caudalímetro modular área-velocidad, la sección transversal del surco se determinó mediante profilómetros, y se registraron los tiempos de avance y recesión. Se utilizó el programa informático WinSRFR para analizar y optimizar cada riego, determinando la eficiencia de aplicación (EA) y la uniformidad de distribución del mínimo (UDmin), y optimizando el caudal del surco (q) y el tiempo de aplicación (Ta). Los valores medios de EA fueron 30,1%, 25,6% y 26,7% en 2007, 2008, y 2009, respectivamente, y los correspondientes valores de UDmin fueron 0,54, 0,61, y 0,67. La optimización mostró que es posible alcanzar valores de EA and UDmin de hasta 87% y 0,86, respectivamente. Pero más importante que conocer los valores concretos de q-Ta, es conocer la relación que maximiza AE y UDmin, por lo que se obtuvo una función que relaciona q y Ta, que fue validada en 2011. Esta función podría ser utilizada en la mayoría de parcelas de la zona de cultivo.

Chufa (Cyperus esculentus L. var. sativus Boeck.) is a traditional crop in the Mediterranean region of Spain, where it is only furrow irrigated. This article analyzes the irrigation performance for this crop, conducting field studies over three consecutive seasons in Valencia (Spain). Irrigation schedule was based on the volumetric soil water content, which was measured with capacitance sensors. Infiltrability was measured with blocked-furrow infiltrometers. An area velocity flow module measured the water flow, the cross-sectional geometry of furrows was determined using furrow profilometers, and times for advance and recession were recorded. WinSRFR software was used to analyze every irrigation event, determining the application efficiency (AE) and distribution uniformity of the minimum (DUmin), and to optimize the combination of furrow inflow (q) and cut-off time (Tco). Average values obtained for AE were 30.1%, 25.6%, and 26.7% in 2007, 2008, and 2009, respectively, and the corresponding DUmin values were 0.54, 0.61, and 0.67. Optimized results showed that it is possible to reach AE and DUmin values up to 87% and 0.86, respectively. However, understanding the q-Tco relationship that maximizes both AE and DUmin is more important than knowing the specific values. A function that related q and Tco was obtained for the typical plot dimensions, and this was validated in 2011. Therefore, this function can be used in most of the plots in the cultivation area., This study was funded by the Regulatory Council of Denomination of Origin Chufa of Valencia of Spain. The authors would like to thank Dr. E. Bautista for his help with the use of the Win SRFR 3.1 software.