Table 4.2 . Application efficiencies for Irrigation management classes in the BRIA and Delta sugarcane areas from the 2013 P2R Water Quality Risk Framework .
Management class |
Application efficiency ( per cent ) |
|
BRIA |
Delta |
A ( lowest risk ) |
> 85 per cent |
> 75 per cent |
B ( moderate-low risk ) |
70-85 per cent |
60-75 per cent |
C ( moderate risk ) |
50-70 per cent |
40-60 per cent |
D ( high risk ) |
< 50 per cent |
< 40 per cent |
Specific practices for optimising water use include increasing inflow , turning off irrigation when it reaches the end of the field , irrigation scheduling , reducing furrow length and automation . New knowledge of these practices is described below .
Automation of furrow irrigation systems is demonstrated to assist in improving the efficiency of furrow irrigation systems .
Sugar Research Australia ’ s ‘ Modernisation of furrow irrigation in the sugar industry ’ project ( SRA 2014 / 079 ) demonstrated significant reductions of applied irrigation using commercially available equipment , were possible ( Gillies et al ., 2017 ). One of the farms , which is similar to many found in the BRIA area , saved 110 ML from the 82 ha automated ; a reduction of approximately 10 per cent . A second site , in the Airville region and more typical of farms in the Delta area , reduced applied irrigation by approximately 20 per cent or 93 ML from automated 27 ha . The automation system was comprised of software and a radio network that was on constant communication between the base station ( located with the computer ) and field radios controlling the starting / stopping of pumps , as well as the opening / shutting of irrigation valves . The performance of each irrigation event was continuously monitored by a network of sensors , e . g . flow meters , pressure sensors , and sensors to detect the completion of an irrigation event . At the three project farms the economic analysis indicated a net benefit to the farmer when making this investment but recognised this may not apply to every farm . To date over 600 ha of furrow irrigation has been automated .
The use of technology ( smart tools ), like irrigation automation and IrrigWeb ( a web-based sugarcane crop model that Burdekin Productivity Services uses to help irrigators make better decisions around how much to apply and when ) is increasing . However , the manual entry of data is recognised as a significant barrier to increased adoption of these smart tools . Overcoming this barrier is being addressed by a project , funded through the National Environmental Science Program ’ s ( NESP ) Tropical Water Quality Hub , ‘ Improving water quality for the Great Barrier Reef and wetlands by better managing irrigation in the sugarcane farming system ’. The project aims to create an efficient and effortless data transfer system between the two smart tools ; i . e . between IrrigWeb and the irrigation automation software , removing the need to the farmer to manually enter information . Irrigation data from the WiSA auto-irrigation software is automatically uploaded to IrrigWeb ( Uplink program ). The crop model then calculates the latest irrigation schedule for that farm , based upon the local weather information . This automated process will reduce the time impost considerably ( a 100 ha farm may have between 10 – 20 irrigation fields , each of which is irrigated between 12 – 20 times per year ) increasing the likelihood the technology will be used to its potential . The next stage of this project is working on ( automatically ) transferring IrrigWeb ’ s newly generated irrigation schedule back into the irrigation automation software . This ‘ Downlink ’ program will again minimise the need for a farmer to manually enter data . The ability to automatically transfer information between independent , smart decision support tools , reduces the barriers to adoption and improves the chance of long-term adoption . By the end of 2018 , it is expected that more than 700 ha of furrow irrigated sugarcane will be automated . At present , four farmers participating in the NESP project are successfully running the Uplink program on their WiSA automation system and IrrigWeb . The Downlink program is currently undergoing desktop testing and is expected to be deployed in early 2019 .
Incorporating high-resolution weather forecasts into irrigation decision support tools , like IrrigWeb , will improve irrigation management that will lead to better water quality outcomes . A National Landcare Program – Smart Farming Partnership project lead by James Cook University will investigate the ability to
27