Uncertainty as a barrier to adoption of mitigation practices in the agricultural sector.

Summary Hidden costs limit the reduction of GHG emissions associated to agricultural productions. Uncertainty is inherent in farmers’ production decisions, and impact them through different drivers: beliefs, risk, information, ambiguity, are just as many elements that can limit the spread of mitigation practices in the agricultural sector. In this thesis, we first present a complete literature review about agri-environmental measures and the diverse approaches of uncertainty in microeconomics and agricultural economics. We then develop a model of adoption decision showing that 3 hidden costs associated to uncertainty can prevent new practices’ adoption in a non-additive way and coexist (option value, risk premium, informational externalities), so that the regulator must socialize them in order to reduce GHG emissions. Then, we implement a land conversion model and extent it in an empirical estimation strategy of the impact of herb yields volatility on the shadow value of grasslands in the French forage mix. The multinomial logistic model is estimated through an instrumental approach using meteorological data. Finally, we make a survey of a sample of farmers in order to measure their attitudes towards risk and ambiguity (Multiple price list) and estimate their impact on nitrogen fertilization decisions, according to the whole application and the splitting practice.