Abstract: Tea plantations are an important N₂O source. Fertilizer-induced N₂O emission factors of tea plantations are much higher than other upland agricultural ecosystems. According to the basic information on characteristics and knowledge of N₂O emissions from tea plantations around the world, we comprehensively reviewed N₂O emission characteristics, production process, influencing factors, and reduction measures from tea plantations. The global means of ambient N₂O emission and N₂O emission stimulated by nitrogen fertilizer application from tea plantations were (2.68±2.92) kg N·hm^-2 and (11.29±9.45) kg N·hm^-2, respectively. The fertilizer-induced N₂O emission factor in tea plantations (2.2%±2.1%) was much higher than the IPCC-estimated N₂O emission factor for agricultural land (1%). N₂O emission from tea plantation soil (a typical acid soil) were mainly produced during nitrification and denitrification, with denitrification being dominant. N₂O emission from tea plantations were significantly related to the amount of fertilizer application. Other factors, such as fertilizer type, could also affect soil N₂O emissions in tea plantations. The main reduction methods of N₂O emission from tea plantations included optimizing the amount and type of fertilizer, amending biochar, and rationally using nitrification inhibitors. In future, we should strengthen in-situ observations of soil N₂O emission from tea plantations at both temporal and spatial scales, combine lab incubation and field studies to elucidate the mechanisms underling tea plantation soil N₂O emissions, and use a data-model fusion approach to reduce uncertainties in the estimation of global N₂O emission. These would provide theoretical support and practical guidance for reasonable N₂O emission reduction in tea plantations.

Key words: tea plantation, N₂O emission, emission factor, fertilizer application rate, reduction measure