Finding balance for dry seasons ahead

Despite recent floods at the end of the twelve year south-eastern Australian drought, more dry seasons are predicted – and now is the perfect time to plan and make sure we are prepared.

In the first Australian systems-scale, interdisciplinary study of its kind, the three year Farms, Rivers and Markets (FRM) project conducted research into how water is delivered, used and conserved in Australia’s farms and rivers, with a view to improving ecological health of river systems and sustainability on farms.

The 60 person-strong research team spanned University of Melbourne faculties and schools, Monash University, and the Murray-Darling Freshwater Research Centre.

University of Melbourne project leader John Langford says innovation across disciplines to do more with less water is a strong insurance policy for farm profitability and river health in a world of more constrained and uncertain water availability. “Through major changes on the farm, in rivers and at organisational levels, we can facilitate effective water use decisions that benefit the community and environment”, he says

“By introducing more flexibility and choice into the way we manage our water resources, we can be more responsive to changing conditions and boost whole system performance.”

FRM research was conducted on the Broken River, as it has many characteristics and management issues in common with the southern Murray-Darling Basin. Water efficiency and farming system experiments were conducted at the University of Melbourne’s Dookie campus near Shepparton and on surrounding farms.

Professor Andrew Western, based at the University of Melbourne’s School of Engineering, says the application of automatic control engineering to river operations has the potential to improve environmental performance and service level for irrigators.

“Slackwater environments are stretches of water in river channels with little or no current and are significant biodiversity hotspots, essential to the long-term ecological health of Australia’s river systems. Automatic control can reduce flow rates and variations in flow rates, and in turn increase slackwater habitat if this objective is built into the system,” says Professor Western.

In addition to helping maintain more appropriate ecological conditions, the system enables water authorities to decide whether the release volume or the ordering times (or both) should be reduced, strengthening flexibility in how rivers are managed.

“Under current practice, irrigators need to order water four days in advance. But depending on the operational priorities set, automatic control systems can deliver water in as little as one or two days,” says Professor Western.

To characterise joint benefits for the environment and agriculture and support proper water use decisions, FRM developed an analysis framework to inform water resource sharing between the agricultural and environmental sectors.

Professor Ben Gawne of the Murray-Darling Freshwater Research Centre says data collection and measurement of species populations, together with demographic modelling, could become a useful tool to inform environmental water planning.

“This understanding of ecological consequences brings us great potential to improve slackwater habitat, conserve wetland ecosystems, and support flood-dependent forests,” he says.

Snow Barlow, from the University of Melbourne’s School of Land and Environment, says FRM research also explored how water can be used more effectively so farms remain economically viable under changing climates.

The Project conducted systems-scale experiments in irrigated dairy farming, broadacre cropping and grazing, and smart irrigation in horticulture and viticulture enterprises.

“The dairy farming system experiment demonstrated that profitability can be maintained under low water allocations, with initial results providing valuable insights to new management strategies,” says Professor Barlow.

In another systems-scale trial, FRM demonstrated the potential of opportunistic dryland summer cropping. The trial was conducted in partnership with Riverine Plains and local farmer David Cook on his property at Pine Lodge, east of Shepparton, Victoria.

“The trial was set up to see if summer crops have a fit in our dryland cropping system, as we have had significant rainfall in recent summers,” Mr Cook says. “As a result of the experience I gained during the trial, I’ve sown and harvested millet for seed production the last two years, in paddocks affected by the floods in 2010 and waterlogging in 2011.

“The cash flow from the millet has more than made up for the winter crop loss, while wheat has been sown straight back into the millet stubble. The ability to do this has totally changed the way we look at summer rain – it now potentially extends our sowing window from two months to six months.”

Professor Barlow says this is an excellent demonstration of the value in research co-development with leading farmers.

FRM is an initiative of Uniwater, a research incubator linking the University of Melbourne and Monash University. It was funded by the National Water Commission, the Victorian Water Trust, the Dookie Farms 2000 Project Fund and the University of Melbourne, and supported by the Victorian Departments of Sustainability and Environment and Primary Industries, the Goulburn Broken Catchment Management Authority and Goulburn-Murray Water.

FRM results were recently released in full through a publications suite including an overview report, factsheets and in-depth reports

www.frm.unimelb.edu.au.