Provided is a carbon dioxide supply assistance device that: measures the environment inside and outside a greenhouse in which plants are raised； obtains environmental conditions； calculates the rate of exchange of carbon dioxide by the plants in the greenhouse on the basis of, from among the environmental conditions, carbon dioxide concentrations inside and outside the greenhouse, the greenhouse ventilation frequency, and the light intensity in the greenhouse； generates environmental data in which the environmental conditions and the rate of exchange of carbon dioxide are associated with each other； obtains, from among the environmental data that an environmental data generating unit previously generated, similar environmental data which are similar to the environmental conditions； calculates the rate at which the plants in the greenhouse consume the carbon dioxide in the greenhouse on the basis of the similar environmental data and the rate of exchange of carbon dioxide； and estimates the relationship between the rate at which the carbon dioxide is supplied into the greenhouse and the rate at which carbon dioxide is consumed, on the basis of the inner volume of the greenhouse, the consumption rate, and, from among the environmental conditions, the greenhouse ventilation frequency.L'invention porte sur un dispositif d'assistance à l'alimentation en dioxyde de carbone qui : mesure l'environnement à l'intérieur et à l'extérieur d'une serre dans laquelle on fait pousser des plantes ； obtient des conditions environnementales ； calcule le taux d'échange de dioxyde de carbone par les plantes présentes dans la serre sur la base des conditions environnementales, des concentrations de dioxyde de carbone à l'intérieur et à l'extérieur de la serre, de la fréquence de ventilation de la serre et de l'intensité lumineuse dans la serre ； génère des données environnementales dans lesquelles les conditions environnementales et le taux d'échange de dioxyde de carbone sont associés le
