APSIM based determination of irrigation attributes and best use of limited water in supplementary irrigation areas of the Australian sugar industry

Abstract

The current industry focus on improving irrigation efficiency has identified the need for a better understanding of the potential gains from irrigation and use of irrigation resources in many sugar producing regions. This paper was conducted as a component of project BS183S, Statewide adoption of best irrigation practices for supplementary and full irrigation districts, to determine a range of irrigation attributes and irrigation strategies for the use of limited allocation in supplementary irrigation areas.Identifying strategies for the best use of limited irrigation resources is difficult with short term field trials. Crop simulation modelling enables these strategies and a range of irrigation attributes to be determined on a long-term basis wherever climatic and soils data is available. APSIM (McCown et al. 1996, Keating et al. 1999) was employed to determine rainfed yield, effective rainfall, crop response to irrigation, potential yield, and irrigation requirement using ?synthetic? climatic data (Hardie and Mallet 2000) for six supplementary irrigation areas of the Australian sugar industry. This information was used to asses current and potential gains from irrigation, identify strategies for the best use of limited allocation, and raise questions about the current level of allocation and irrigation infrastructure in the Proserpine, Sarina, Mackay, Bundaberg, Mareeba and Childers areas.