Bright outlook for irrigation sustainability challenge
Just as farming is becoming more technical, DPI is increasing its use of satellites to help irrigators make the best use of available water.
The drought forced Victoria’s irrigators to halve their water use between 2004 and 2009 while maintaining farm-gate income at $3.3 billion. Armed with crop data from satellite technologies, Dr Des Whitfield, a Senior Research Scientist from DPI Tatura, is confident that farmers will continue to be able to produce more with less.
DPI is using satellites to develop more accurate estimates of the amount of water needed to maximise yields from irrigated crops without damaging the environment. “The quest for maximum yield invariably results in over-irrigation, which not only wastes water, but also leads to environmental problems, like shallow watertables and salinity,” explained Dr Whitfield.
The need to return water was the main reason that the National Water Commission supported the early satellite research by DPI in 2007. The DPI team mapped water use of irrigated crops in all of the major irrigated areas in the Murray Darling Basin. They used Landsat images to provide data at a scale of 30x30 metres, over areas as large as 180x180 kilometres.
“Our work showed that most Victorian crops were under-irrigated during the drought years, as irrigators cut back on water use. We nevertheless found a range of instances of over-irrigation during those years,” Dr Whitfield said.
Those initial project findings have led to new applications in which irrigation can be tailored to suit individual crops to maximise their yield potential.
It is not just over-irrigation but the technology can also show where under-irrigation contributes to low yields.
“Satellites can provide a lot of information about crops in the field, and better insights into the many reasons why crops produce low yields,” he said.
“Hopefully in four or five year’s time, farmers will be using satellite information to tailor irrigation to individual crops and fields,” Dr Whitfield said.
This very new technology provides regional perspectives of crop performance, and has powerful applications.
“Satellites will guide farmers on how much irrigation water is needed by different fruit, vine and nut crops grown in Victoria. Like the widespread adoption of new technologies by farmers, satellite technologies are also rapidly expanding DPI’s research and analysis capabilities,” he said.
Research contact: Dr Des Whitfield, DPI Tatura, des.whitfield@dpi.vic.gov.au
This project is co-funded by the Department of Primary Industries Victoria, the CRC for Irrigation Futures and the National Water Commission
