Abstract: Carbon capture and storage (CCS) technology is one of the key strategic emission reduction technologies, which made a great contribution towards emission reductions. However, there still exists controversy of CCS largely due to the safety problems caused by its leakage. Leakage of CO₂ captured in geological structures has a threat to the cultivated crops on the ecosystem suroundings. Thus it has great significance to carry out CCS leakage assessment on crops. In this study, the millet crop, which is the main grain in the northern region, was used as experimental object. Effects of CCS leakage on the physiological characteristics of millet were studied through a self-designed pots experiment simulation CO₂ leakage by analyzing the SPAD, plant height, panicle diameter, panicle length, plant biomass and yield of the millet plant. The results showed that CO₂ leakage into shallow soil caused the decrease significantly for leaf green value (SPAD), fresh weight in the shoot, dry weight in the ground and the weight of the grain ear, which proved that the CO₂ leakage of the storage had a serious negative impact on the physiology and yield of the millet, and the yield of millet decreased by 34.92%. It was also observed that the number of branches of root increased by 10%, and the depth of the root burial became shallower. It indicated that the number of the millet roots has response for CO₂ leakage. Meanwhile, the weight per panicle, the panicle diameter was coarse and the panicle length changed significantly.

Key words: Millet, CCS Leakage, Physiological response, SPAD, Yield, CO2 capture and storage