Evaluation of Best Management Practices for N fertilisation in regional field vegetable production with a small-scale simulation model

Assessing the environmental impact of field vegetable production on a regional basis is a challenging task, since vegetable farms are often scattered. In order to use a soil–plant–environment–economics model as an assessment tool, a method is suggested that allows Best Management Practices (BMPs) for N-efficient field vegetable production to be tested and evaluated on different spatial entities. The model farm concept was exemplarily demonstrated on field vegetable production in the region of Baden-Wurttemberg, Germany. Two scenarios using different fertiliser strategies illustrate how the implementation of BMP can be evaluated at regional, sub-regional and farm level. Simulated results show how the area-wide enforcement of the Nmin method in Baden-Wurttemberg, as the first step to implement BMP, would lower the N leaching potential of field vegetable production by 66%. At sub-regional level, the results reveal that current targets stipulated by German legislation may still not be achieved in smaller areas with intensive field vegetable production.