1) How much should the tax be so as to encourage the farmer to reduce his TFI by 30% per hectare (test a 10% tax, then 30%, 50% and 70%) ?
The tax must at least be of 50% so as to encourage the farmer to reduce his TIF by 30% per hectare.
2) Does the tax increase have an impact on cropping patterns ?
The tax increase has an impact on cropping patterns and their income. The higher the tax, the lower the income. And more money thus enters State funds.
3) Is it possible to encourage the farmer to switch to Integrated Pest Management at cropping system level (systCI) with this policy ? Explain.
To encourage the farmer to switch to Integrated Pest Management at cropping system level, a 200% loan tax would be necessary.
4) Compare the acceptability of this tax with that of subsidies.
Subsidies costs the State whereas taxation allows the State to make money. As for the farmer, his income becomes more significant with subsidies. An average TIF of 2/ha requires a 200% tax. The acceptability of such a significant tax can be questioned, while the subsidy has been approved.
Summary of results :
| Crop | Disruption level | Scenario 1 | Scenario 2 | Scenario 3 | Scenario 4 | Scenario 5 |
| Total TIF | 4.5 | 4.5 | 4.5 | 2.9 | 2.008 | |
| Tax | 0% | 10% | 30% | 50% | 200% | |
| Soft wheat | Rais | 33.333 | 33.333 | 33.333 | ||
| Soft wheat | protI | 33.333 | ||||
| Soft wheat | systCl | 25 | ||||
| Rapeseed | Rais | 33.333 | 33.333 | 33.333 | ||
| Rapeseed | protI | 33.333 | ||||
| Rapeseed | systCl | 33.333 | ||||
| Winter barley | Rais | 33.333 | 33.333 | 33.333 | ||
| Winter barley | protI | 33.333 | ||||
| Winter barley | systCl | 25 | ||||
| Hemp | systCl | 16.667 | ||||
| Income | 49850 | 48327 | 45280 | 42648 | 28296 |
You can download the solution and check that you wrote the model correctly and obtained the same solution: modelEco_ParisBasin_tax.gms
