Abstract:In China, surface ozone (O3) has become a major secondary pollutant as the fine particulate pollution problem was largely addressed. As nitrogen oxide concentrations continue to decline and climate warming intensifies, urban ozone formation becomes more sensitive to VOC emissions. With the continuous increase of urban green space in recent years, the emissions of Biogenic Volatile Organic Compounds (BVOCs) have also increased, and thus played an increased role in ozone formation. This paper presented a comprehensive review of the interactions and mechanisms between BVOCs emissions and ozone concentrations in urban areas. We first reviewed the current states and trends in the response of plant physiological state and BVOCs emission rate to environmental stress, especially the elevated O3 concentration, with a particular emphasis on previous studies that focused on the effects of O3 on isoprene and monoterpene emission rates of various plans. We then summarized the role of BVOCs plays in O3 formation. Based on the review of the existing studies, we found a few knowledge gaps and identified several priorities for future research:(1) studies on quantifying the BVOCs emission rate of different urban tree species to build a more comprehensive database for BVOCs emission rate that can be used to optimize the parameters of BVOCs emissions models, and thereby to improve the precision of the fine-scale BVOCs emission estimation; (2) Exploring the interaction and comprehensive influence of various environmental factors on BVOCs emissions from urban plants, such as pollutant concentration, temperature, and humidity; (3) Quantifying the contribution of plant BVOCs to O3 formation and its effect on plant resistance to air pollution, which aims to provide a theoretical basis and reference for the selection of tree species for urban greening and the reduction of urban O3 pollution.