Development of the FBC model to estimate the nitrogen available from fertility -building crops in organic rotations

Summary

The FBC (Fertility Building Crops) model has been developed as a planning tool to provide organic farmers with information about how much nitrogen will be available in the soil at different stages following the ley phase of the rotation. It predicts the likely crop yields under this level of nitrogen supply and provides an estimate of how much nitrogen will be lost by leaching and denitrification so that if necessary the grower can examine the effects of modifying the rotation to improve the efficiency of nitrogen use and minimise losses. The model is easy to use and requires only the sort of information that is readily available to commercial growers. Although it appears to provide realistic simulations of a range of crop rotations and conditions, it has not yet been fully validated.