PARTICIPATORY IRRIGATION RESEARCH AND SCHEDULING IN THE ORD: R&D

THE EXPERIENCE gained from research and extension of irrigation technology in the recently-developed Ord sugar industry could benefit older schemes such as the Burdekin. This paper provides a brief review of the irrigation research conducted in the Ord since 1996. A companion paper will review the researchextension- grower interaction that guided the research and led to the development and adoption of a web-based scheduling system. Five replicated scheduling experiments were conducted to test yield response to various irrigation schedules based on Class A pan evaporation, neutron moisture measurements, and the APSIM-Sugarcane model. The research led to the development of average monthly irrigation intervals for different soil types and cropping cycles. It was soon evident that the average irrigation cycles were often wrong when weather conditions were not ‘average’. The R&D direction turned to real-time methods for monitoring crop water use and irrigation scheduling. Daily crop evapotranspiration (ETC) was measured using a Bowen ratio energy balance (BREB) system. A crop factor regime was established using reference ET (ET0). A web-based system was developed to accept grower details on soil type, planting and ratooning dates, and to report calculated soil water deficit and days to the next irrigation for each paddock. Ord growers now access the web program to schedule irrigation.