The Australian cotton industry is a global leader in water use efficiency. As irrigation water continues to become an ever-more-scarce resource, the industry is increasing its commitments to continuous improvement in water productivity and demonstrating its responsible use of the shared water resource. 

This five year research and development project focused on improving on-farm water management and boosting productivity through the efficient use of water resources. This has been achieved through primary activities that included (1) the development of the weather based technology IrriSAT to guide irrigation scheduling, (2) the provision of a technical specialist to lead and coordinate industry wide water use efficiency campaigns and (3) benchmarking water productivity across the Australian industry and identifying long term trends in water productivity over the last three decades. 

The refinement and promotion of the IrriSAT technology to guide irrigation water scheduling has resulted in excess of 1500 growers and consultants becoming registered users. This has been achieved as a result of a range of promotional activities including webinars, workshops and field days. Commercial industry service providers have also taken up the use of IrriSAT, with Goanna Telemetry now having fully integrated the IrriSAT approach into their GoSAT web interface, integrating soil moisture probes and IrriSAT data into a combined irrigation management package for growers. 

To support and coordinate the improvement of irrigation management and water productivity in the cotton industry, three officers have provided Technical Specialist input to the CottonInfo team – Janelle Montgomery, Ali Chaffey and Ben Crawley. These officers have been incorporated in the CottonInfo team and have led a wide range of activities. These activities have included, the Irrigation and Nitrogen tours, which brought together researchers, advisors and growers to raise awareness of industry funded research programs and promote best practice, engaging with 519 participants across seven locations in eastern Australia. More recently, the Technical Specialist, in partnership with the CottonInfo team, has coordinated two major field days where approximately 220 growers and advisors were directly exposed to the latest technologies using siphon-less irrigation methods. Participants provided clear feedback that they had gained knowledge which would result in them making informed decisions regarding adoption of more efficient and water productive irrigation practices.  The field days have resulted in YouTube videos and detailed information booklets which are now being accessed by growers across the industry.

Benchmarking of water productivity has shown that growers continue to produce more cotton from less water – improving their status as the most water efficient producers in the world. Long term trends in rainfall and irrigation inputs have declined over time, but increasingly higher yields are still being produced. This has meant water productivity has increased at a rate of around ¼ bale more cotton per decade from each ML of total water, and roughly 1/3 more cotton per decade for each ML of irrigation water. Water productivity has improved from 1.12 bales per megalitre in 2012/13 to 1.20 bales per megalitre in 2017/18. Cotton growers are improving their management of irrigation water, for example by reducing losses to evaporation and seepage during transmission and storage losses. A comprehensive study of long term trends in irrigated cotton water productivity has been completed and its results are nearing publication in the scientific literature.

This research is helping to quantify and demonstrate that cotton growers are improving the productivity from every drop of water available, and this provides a platform for the industry to demonstrate and communicate its high level of stewardship of a crucial natural resource that needs to be shared – water.

Additionally, more efficient techniques have been developed under this project to monitor water productivity. An interactive dashboard has been developed which allows all growers participating in benchmarking, and their advisors, to track their level of water productivity, and more importantly to compare it with their peers, regionally and nationally. Further research is now taking place under a new project that will apply these new techniques to more closely identify the trends and drivers of water productivity, on an annual basis in both irrigated and dryland Australian cotton.

If cotton is the crop of choice in many irrigated systems it is because the industry has made great gains in water productivity and cotton is the most profitability use of the limited water available to growers.

For further information please contact 

david.perovic@dpi.nsw.gov.au or ben.crawley@dpi.nsw.gov.au