N Banking
NGN Comparison of nitrogen-based demand and banking strategies to aid N decision making in SE NSW
Project Funder: GRDC
Project Partners: FarmLink Research, CWFS, Riverine Plains, University of Melbourne
Project Code: PROC-9176592
Project Duration: 2022-
Project Location: SE NSW
Background
Grain growers across a large number of National Grower Network forums have identified the difficulties in matching N supply to crop N demand. The problem is the approach taken to estimating N supply is based on N demand and N demand has a high level of uncertainly associated with it because of the high error associated with predicting August to October rainfall.
A new approach is proposed and is described by Meier et al. (2021), which seeks to reduce uncertainty of N supply. The approach is referred to as N banking and seeks to maintain a specified/pre-determined soil mineral N level that is topped up each winter to the target N bank level ignoring crop N demand outlook. In the N banking strategy, the crop draws upon the N bank and together with extra mineralisation in high rainfall years this approach ensures high N demand years are matched with adequate N supply.