Muller-Feuga, A.

The impact of agriculture on the climate remains underestimated due to the systematic exclusion of annual crops from carbon budgets. Considered too ephemeral, these crops are nevertheless responsible for the absorption and storage of approximately one-third of the carbon biofixed by photosynthesis, with half-lives that are not limited to a single season but extend on average over 8.9 years. The kinetics of variation in carbon capture and release by cultivated plants over the half-century were simulated using two error functions which made it possible to complete the probabilistic calculation of the carbon balance components. In 2023, all cultivated plants crops, grasslands, and forest plantations had a stored carbon half-life of 17.6 years. They had removed 39.2 billion tonnes of CO2/year from the atmosphere, more than global emissions from hydrocarbon combustion. Simulation of time distribution suggests that cultivated plants would have constituted a net stock of 124 billion tons of carbon by 2023, based on 455 billion tons of CO2 removed from the atmosphere, or 14% of its atmospheric mass. Given the importance of carbon capture and storage by cultivated plants, both in duration and quantity, rural activities should be integrated into carbon balances and the resulting climate strategies and recognized as a carbon capture and storage (CCS) device in carbon cycle regulation policies. This recognition would allow for the fair valuation of the work of farmers and foresters as part of the ecological transition, particularly through remuneration mechanisms such as carbon credits.