WATER MANAGEMENT POLICIES TO IMPROVE SURFACE IRRIGATION

An economic and environmental analysis of various policy measures is undertaken in this paper. A bio economic model of agricultural activities in the Bardenas irrigation area of the Ebro basin in Spain is constructed. The model includes production function of crops, estimated with EPIC crop growth package. The model results show the effects on crop yields, water and nitrogen demand, and on control nitrogen pollution when the different measures are considered. These measures are evaluated by their cost efficiency. A standard in water applied by 25 per cent is the best measure to abate nitrogen pollution, following by the quantitative limit on applied fertilizer and nitrogen price increases. The limit on water applied is an appropriate measure to avoid the overuse of water resources, and this option would require the establishment limits on concession to the irrigation district associations, measure the flow and control the water applied by farmers