Monday, November 5, 2007 - 10:45 AM
33-5

Designing Deficit Irrigation Programs with AquaCrop--The European Commission DIMAS Project.

E. Fereres, IAS-CSIC and University of Cordoba, Apartado 4084, 14080, Cordoba, Spain, P. Steduto, Land and Water Division, FAO, Viale delle Terme di Caracalla 00100, Rome, Italy, G. Economou, Agricultural University of Athens, 75 Iera Odos, 11855, Athens, Greece, M. Benabdellah, IAV Hassan II. Dept. des Sciences Humaines, Rabat-Instituts, B.P. 6202, Rabat, Morocco, N. Ben Mechlia, INAT, 43 Av. Charles Nicolle, 1082, Tunis, Tunisia, R. Kanber, University of Çukurova, Agric. Faculty, Balcah, 01330, Adana, Turkey, M. Shatanawi, University of Jordan, Faculty of Agriculture, Amman, Jordan, M. Todorovic, CIHEAM – Mediterranean Agronomic Institute of Bari, Via Ceglie 9, 70010 Valenzano (BA), Italy, and G. D’Arcangelo, CBC, Corso Roma 2, 71100, Foggia, Italy.

Although irrigation uses about 80% of all diverted water in the Mediterranean Basin, increased demand for other uses coupled with water scarcity is putting unprecedented pressures on reducing the share of freshwater used in irrigation. Deficit irrigation is not only an option to reduce irrigation water use, but is becoming the norm in water scarce areas. To investigate the potential of Deficit Irrigation (DI) for reducing agricultural water demand, the European Commission funded in 2005 a research project (DIMAS) in seven countries of the Basin. In DIMAS, the DI concept is the subject of multidisciplinary research at different geographic locations, different scales, and with different annual (wheat, cotton, sunflower) and  perennial (olive, pistachio, citrus) crops. The aim is to develop a workable, comprehensive set of deficit irrigation (DI) strategies that can be disseminated among various agricultural systems of the Mediterranean Region. Research activities include field experiments using different DI programs and their use in the validation of the FAO model,  AquaCrop, which in turn will be used to design the DI strategies under different water scenarios. In DI, there are two options; one, when the constraint in supply is moderate, is to cut back from full irrigation to a DI program that usually does not reduce crop yields significantly; however, under severe scarcity, the critical issue is when to apply a very limited amount of irrigation water.  To exemplify the degree of water scarcity in some of the irrigated areas in the Mediterranean Basin, suffice here to say that two of the Project areas, located in Italy (Capitanata) and Spain (Guadalquivir Valley) and encompassing more than half a million acres have, at the start of the 2007 irrigation season, an anticipated irrigation supply of only three and six inches, respectively (800 and 1,500 m3/ha). The development of DI programs must be based on exploring these very different scenarios with the aid of a simulation model. A computer model such as AquaCrop, is the ideal tool to narrow the options down to just a few that can then be analyzed taking into consideration the bio-physical, economic, social and political conditions of each crop and area. The presentation will emphasize how AquaCrop is assisting in the development of DI programs for the different areas and countries involved in the DIMAS project.