Crop under the trees does not appear as a single system, more or less uniformly distributed over the plot, but as a series of independent cells, each having a specific planted species, a growth stage, a water demand, etc…

To achieve this, the STICS model will be run independently on each cell.

The water and nitrogen competition module will use as inputs the tree water and nitrogen demand and the crop water and nitrogen demand from each cell. After completion, the module will return to each cell the mass of water extracted by trees and crops.

The difference in soil discretization between Hi-sAFe (voxels of several cm) and STICS (mini-layers of 1 cm) requires performing an aggregation or disaggregation calculation before and after the competition module for water and nitrogen.