Assessing soil nitrogen dynamics in Vertosols cropped to cotton in subtropical Australia

This project assessed the contribution of Vertosols to the nitrogen supply of cotton in Darling Downs region, Australia. Two years of nitrogen dynamics measurements throughout the soil profile under field and laboratory conditions demonstrated that, on average, 87 per cent of nitrogen was supplied by the soil to the cotton crop. This research provides a practical framework for establishing a sustainable nitrogen management strategy to enable efficient use of nitrogen in irrigated cotton production. The results of this research are potentially applicable to similarly managed cropping systems in vertosols