Quantifying the impact of an abrupt reduction in mineral nitrogen fertilization on crop yield in the European Union.

Contemporary crop production in Europe relies on nitrogen (N) fertilization. Fertilizer prices soared in 2021-2022, and remained at historical high levels in 2023. These high prices invoked an immediate concern on the possible consequences for Europe's food production.

A fully integrated isoprenoid emissions model coupling emissions to photosynthetic characteristics.

The lack of a mechanistic basis has hampered modelling isoprene emission responses to environmental drivers, in particular the simulation of isoprene emissions under different CO₂ concentrations. Here, we advance previous semi-mechanistic model formulations by introducing a model that explicitly links electron availability for other purpose than carbon assimilation (or available energy for secondary metabolism processes; supply-constraint) and enzyme activity (capacity-constraint) to emissions. We furthermore investigate the sensitivity of the model to variations in photosynthetic and emission-specific parameters.