Adoption of more uniform sprinkler systems involves a trade off between increased capital expenditure on equipment and the benefits associated with reduced water application when application is uniform. An empirical analysis of the economics of lettuce production, grown using sprinkler systems under the windy conditions of the Swan Coastal plain in Western Australia is presented, where the yield response to water exhibits eventual declining marginal productivity. A range of sprinkler designs that have been field-tested for performance were examined. The optimal per-crop water application for the least efficient system was up to double the application rate of the most efficient system. However, the economic analysis demonstrates that there are clear incentives for adopting more water-efficient systems despite the higher capital cost, because of the yield depressing effect of over-watering. Sensitivity analysis demonstrates substantially poorer incentives for improving irrigation efficiency when yield relationships follow a Mitscherlich functional form.

capital, crop yield, economic analysis, equipment,irrigation, irrigation systems, lettuces, mathematical models,performance tests, precipitation, sandy soils, soil types, spatialdistribution, sprinkler irrigation, sprinklers, water use, water useefficiency, Australia, Western Australia, Lactuca sativa, Australasia,Oceania, Developed Countries, Commonwealth of Nations, OECD Countries,Lactuca, Asteraceae, Asterales, dicotyledons, angiosperms,Spermatophyta, plants, eukaryotes, Australia, spray irrigation,watering, Agricultural Economics (EE110), Horticultural Crops (FF003)(New March 2000), Plant Production (FF100), Soil Water Management(Irrigation and Drainage) (JJ800) (Revised June 2002) [formerly SoilWater Management], Agricultural and Forestry Equipment (General)(NN400), Mathematics and Statistics (ZZ100)

• Journal Article

• Ag Water Resource Economics
• Irrigation Systems