[Effects of Elevated Ozone on Biogenic Volatile Organic Compounds (BVOCs) Emission: A Review]

With the global increase of tropospheric ozone (O₃) and complex interactions between biogenic volatile organic compounds (BVOCs) emissions and tropospheric O₃ concentrations, this review summarizes current research progress and future research prospects in terms of the effects of elevated O₃ on BVOCs emissions. The main progress included impacts of BVOCs categories, plant functional types, O₃ sensitivity of plants, the O₃ stress level on the response of BVOCs emissions to single O₃ stress, and the combined effects of elevated O₃ and temperature, carbon dioxide (CO₂), drought, and nitrogen (N) deposition. Results indicated that most published results reported no change in BVOCs emissions in response to increasing O₃ concentration. Specifically, decreasing effects of O₃ on BVOCs emissions were more obvious in studies on isoprene and deciduous species, whereas studies on monoterpenes and evergreen plant species showed more results with an increasing trend as well as acute O₃ exposure experiments. There was an increased tendency of monoterpene emissions to the combined effects of O₃ and temperature or N deposition. However, the combined effects of O₃ and CO₂ decreased isoprene emissions. Given that studies on the effects of O₃ on BVOCs emissions remain scarce, more complete experiments are needed that consider differences between short-term and long-term or individual-level and ecosystem-level. Furthermore, future research should strengthen the multi-factor interactive studies, particularly on O₃ and other global change components and biotic and abiotic stresses, to assess BVOCs emissions from terrestrial ecosystems in response to O₃ pollution both currently and in the future, which will provide valuable theoretical support to air pollution control.