...
Conclusion
Even though it took me years to figure it out, the approach is fairly simple:
- Explode concentrations to balances of concentrations
- Identify a healthy zone and map a model to it
- Run the model to predict the yield class of new value
- If unhealthy, identify the target zone
- Draw the path to the target zone using a perturbation vector
The tricky part is the one after step 4. Correcting a plant ionome will need precise fertilization with the right chemicals and, above all, the right professional agronomist.
All computations done for this article can be found in a R Jupyter notebook
here.