— 43 IREC Farmers' Newsletter No. 200 — Spring 2018 Temperature data from the rice field at two dates is shown in Figure 2. On both of these dates, there were significant cold events. The first date is 15 February 2018, which for a late-sown crop in NSW, Australia would fall close to the critical microspore phase. If the rice panicle was subject to the cold ambient temperature of 6 °C, there would likely be a significant negative impact on yield. The second date is 8 April 2018, when there would not be such sensitivity to cold because the rice has passed the microspore phase. On the first date, the water was around 200 mm. It can be seen that this provided effective insulation against the cold temperatures at panicle height (around 200 mm), keeping the temperature there above 12 °C. The water effectively maintains warmer temperatures above the surface of the water through its stored energy. In contrast, at the second date, no such insulation was provided as the water had been nearly drained. This provides a useful illustration of how temperature at multiple heights can be used to manage rice paddy water depth to effectively insulate the crop from cold temperatures. Where to from here The developed in-field sensing systems using MCPs have proven to be robust and well suited to the rice growing environment. Parameters measured by the sensing system are applicable to automation, and this would provide maximum benefit for rice growers. A smart automated rice irrigation system that linked this sensing data with weather forecasts and automated water control has the potential to deliver significant water saving and productivity gains. Acknowledgments The authors acknowledge the support of project funding from AgriFutures Australia, and thank Garry Knagge, Chris Morsehead, Russell Ford, Alex Schultz, Don Griffin and Samuel North. More information Dr. James Brinkhoff Research Fellow - Environmental and Sensor Systems M: 0439 939 205 E: [email protected] For more information on the method, see the full paper at http://www.mdpi.com/1424-8220/18/1/53 The developed in-field sensing systems using MCPs and WiField loggers are available from Tom Dowling at Goanna Telemetry: [email protected] Figure 2. Temperature profiles measured by the MCP during cold temperature events (15 February 2018 and 8 April 2018 6 am). The measured water depth is indicated with blue shading. — 43 IREC Farmers' Newsletter No. 200 — Spring 2018 In-field water sensing BACK TO CONTENTS PAGE