Standard theories for water movement, solute transport and uptake by roots can be applied to closed, recirculating cropping systems, even when coarse substrates are used. Some of these systems, such as bedding systems or potting plants, are vulnerable to accumulation of solutes in the root zone, which may be harmful to crop development. A two-dimensional simulation model for the above-mentioned processes is briefly described. This model can be used, amongst other possibilities, to search for good fertigation strategies in order to minimise solute accumulation in the root zone. This modelling approach can largely reduce the number of experiments. Some simulated scenarios showing different distributions of the electrical conductivity in a layer of 15-cm coarse sand are presented. This study is not meant to be an extensive search for the best fertigation strategy but to demonstrate how the simulation model can help in finding alternative strategies.
- zero-sink uptake