Dr. Pierre-Marie Aubert:

On the agriculture sector, the Deputy asked whether we should tax emissions from the agriculture sector. She mentioned the problem of potential emission displacement. We need to consider what the basis for taxation would be. Would it be on the basis of the level of efficiency or on the basis of absolute level of emission? The choice makes a big difference. Taxing on the basis of efficiency might be a better option if we are to consider that at the global level the most efficient production systems have to be favoured. In any case, as I said in my introductory speech, we need to go for both efficiency improvements and overall reduction in the production if we are to meet the target that we have set.

If the current technologies to increase the efficiency level in agricultural production are implemented at scale, they might have some impact on the way landscapes are managed in Ireland. In order to complement feed and use methanogenesis approaches, cattle need to be kept under shelter at least for a certain number of hours. It will be necessary to change completely the way Irish cattle are raised and they will no longer be totally grass-fed. That will have a significant impact and needs to be carefully considered.

There are two other things related to the potential displacement that could result. If the approach is in terms of absolute levels of emission, the question would be to what extent farmers at an individual level or the collective level would decrease the size of the herd. If the size of the herd decreases, with what can it be replaced? Ireland is import-dependent for its food in the sense that it does not cover its needs with most staple products coming from other countries. If Ireland replaces bovine herds by something else allowing it to meet the needs of its population, that might also be something interesting. The country could re-diversify the production at the national level which might also be a very good option.

I wish to discuss the symmetric option which would be to reward good practices. The options are to tax greenhouse-gas emission or reward sequestering practices. That leads to the Deputy's question on afforestation and how to favour afforestation practices at farm level. In considering the types of incentives to favour sequestration at the farm level, it is important that the kind of practices favoured to sequester carbon will not change over time. To put it simply, if people sequester carbon and build carbon stocks in soil by grazing in a particular way or by growing crops without tilling so on, if at some point in time there is a change in that practice, all the carbon that has been sequestered in the soil will be released. There is a big issue. If it is decided to favour practices to store carbon in agricultural soil, it is necessary to ensure that practices will not change over time, otherwise it will be totally missed.

It is similar with afforestation in the sense that it depends on what the trees that are planted will be used for and when. I do not have clear examples of countries where agroforestry practices have been highly incentivised. As we discussed over lunch with Professor Masson-Delmotte, agroforestry might be one of the best options to store carbon in agricultural land. I do not know the exact potential in the Irish context given that one of the main interests of agroforestry in France or Mediterranean countries is that it limits the drying effect of sun. I do not think that is an issue here where the level of precipitation is expected to increase rather than decrease.