Activity 15 – Cropping patterns – Solution

Solutions :

In the “intensive”, “sustainable” and “integrated pest management” management systems, each agronomic rule can be expressed in terms of cropping pattern :
– oilseed crops cannot be grown more than once every three years on the same plot, that is to say that oilseed crops (i.e. rapeseed in our model) represent 1/3 of the cropping pattern.
– cereal crops cannot be cultivated more than two years in a row, that is to say that the sum of cereal crops (wheat and barley) represent 2/3 of the cropping pattern at the most.
– each cereal crop can be grown on half of the area dedicated to cereal crops at the most, that is to say that each cereal crop is cultivated on half the cropping pattern of the sum of cereal crops at the most.

For the last rotation, that of “integrated pest management”, what changes is as follows :
– hemp is grown once every six years, that is to say that hemp is cultivated on 1/6 of the total land area dedicated to “integrated pest management system”.
– Cereal crops cannot be grown more than one year, that is to say that the sum of cereal crops (wheat and barley) represent ½ the cropping pattern in “integrated pest management system” at the most.

The farmer chooses to cultivate 33.33 ha of rapeseed, soft wheat and winter barley in a sustainable management system. The income of the farmer is 49850€.

The results are as follows :

You can download the solution, check that you wrote the model correctly and obtained the same solution : modelEco_ParisBasin_rotations.gms