Volatile organic compounds emitted from vegetation and their contribution to the terrestrial carbon cycle
植物源VOCs及其对陆地生态系统碳循环的贡献

Many investigations in the past decades have suggested that volatile organic compounds (VOCs) played an important role in tropospheric chemistry in the process of photochemical reaction with inorganic O_x, HO_x and NO_x. Most of researches about VOCs emitted from vegetation mainly focused on: (1) what are the role of VOCs emitted from vegetation to troposheric chemistry and their mechanism? (2) Why do many plants emit VOCs, and what is their eco-physiological significance? (3) What are main environmental factors to control VOCs emission form plants and how? (4) At different time or space scales, how do the emission potential and pattern change? The authors drew briefly conclusions and new progress of above topics in this paper. A substantial amount of carbon is emitted annually by terrestrial vegetation as VOCs, which is regarded as a loss of photosynthetically fixed carbon and important component of the carbon budget of the terrestrial biosphere. Up to date, the significance of VOCs, emitted from vegetation, to carbon loss for the regional or global carbon cycle is controversial. Due to uncertainties associated with vegetation VOCs emission, models of carbon cycle all considered that VOCs do not play an important role in the carbon balance, and omitted initially them. Recently, some researchers however pointed out that, while VOCs flux estimates are small in relation to net primary productivity (NPP) and gross primary productivity (GPP), the amount of carbon lost as VOCs emission can be highly related to net ecosystem productivity (NEP), especially in some vegetation types or specific regions. Therefore, the authors here discussed emphatically the potential importance of VOCs emitted from vegetation to carbon cycle or carbon balance, and forecasted some important issues about VOCs in the future in China.