Greenhouse gas emissions of N2O were measured over a period of 2 years commencing in March 2013. Moveable gas collection chambers (0.8 x 0.8 m wide x 0.5 m high) constructed from stainless steel and clear polycarbonate panels, with extensions (0.5 m) added to increase chamber height as the crop grows, were installed in each plot. The top surface panel of these automatic chambers is divided into two lids that open away from the top of the chamber to reduce rainfall interception. Chambers are clamped to open stainless steel base units (0.8 x 0.8 m wide x 0.15m depth); with two base units installed in each plot, 0.5 m apart, so that chamber position can be alternated within each plot on a weekly basis to minimise micro-climatic artefacts. The chambers were pressure-vented during closure time with two fans (80 mm dia. each), but programmed to be opened automatically if the temperature in the chamber exceeded 50oC or if the site received more than 0.5 mm rain in 5 minutes (in order to maintain water content under chambers similar to the rest of site).The concentrations of N2O in gas samples were measured using the following procedure. Chambers for each plot were closed for 30 minutes and open for 60 minutes, with each chamber sampled sequentially each 3 minutes over 30 minutes of closure period, with ten measurements during that time (30 seconds each). This allowed 16 measurements of flux rates per day for each individual chamber.The emissions were determined by calculating the linear increase in N2O concentration during the closure period (using least squares regressions) and corrected for air pressure, air chamber temperature and the chamber volume/area ratio. Flux values were tested for a significant linear trend based on a t-test. Data was discarded if there was no significant fit (ɑ=0.033) of values to the predicted linear model or chamber lids were opened due to rainfall or high temperature.