Many VOCs are reactive in the atmosphere, may produce secondary organic aerosol (SOA), and keep photochemical ozone concentrations high by VOC-involved reactions. Accumulated studies have shown the importance of terrestrial ecosystems which can be sinks and sources of VOCs. The research progress in the exchange of volatile organic compounds (VOCs) between terrestrial ecosystems and the atmosphere was reviewed in this paper. Representative VOCs emitted from terrestrial ecosystems are low-molecular-weight oxygenated VOCs including methanol, acetone, formic and acetic acids, and terpenoids, including isoprene and monoterpenes. Terpenoid emissions have been intensively investigated from the leaf to the canopy level using advanced analytical systems, including proton-transfer-reaction mass spectrometry. Environmental factors, including temperature, light intensity, carbon dioxide and ozone concentrations, and water stress have been reported to affect terpenoid emissions from plants. The combined effects of these environments influence terpenoid emission additively or interactively, and are important in terms of VOC emission estimates against ongoing climate change. Isoprene is most abundantly released into the atmosphere among VOCs; the potential reasons why some plants release such large amounts of carbon as isoprene were summarized in this study. Among oxygenated VOCs, some compounds, including isoprene oxygenates methacrolein and methyl vinyl ketone, are bidirectionally exchanged, and both atmospheric chemical reactions and reactions under oxidative stress in leaves have been regarded as involved in bidirectional VOC exchanges. Bottom-up process-based models and top-down inverse models have been developed to estimate global and local terpenoid emissions. To validate the accuracy and precision of the models, the collection of additional in-situ ground truth data, such as long-term flux measurement data, at various sites is required. Otherwise, these models may still leave large uncertainties compared with CO₂ flux models that can be validated with a large number of ground truth flux data.

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评论：陆地生态系统与大气之间的挥发性有机化合物交换

许多挥发性有机化合物在大气中具有反应性，可能产生二次有机气溶胶（SOA），并通过涉及挥发性有机化合物的反应使光化学臭氧浓度保持较高水平。积累的研究表明，陆地生态系统的重要性，而陆地生态系统可能是VOC的汇和源。本文综述了陆地生态系统与大气之间挥发性有机化合物（VOCs）交换的研究进展。陆地生态系统排放的代表性挥发性有机化合物是低分子量的含氧挥发性有机化合物，包括甲醇，丙酮，甲酸和乙酸，以及萜类化合物，包括异戊二烯和单萜。使用先进的分析系统，包括质子转移反应质谱法，对从叶片到冠层的萜类化合物排放进行了深入研究。环境因素，包括温度，据报道，光照强度，二氧化碳和臭氧浓度以及水分胁迫会影响植物中的萜类化合物排放。这些环境的综合影响会相加或交互地影响萜类化合物的排放，对于针对不断变化的气候变化的VOC排放估算而言，这一点很重要。在VOC中，异戊二烯释放到大气中的含量最高。这项研究总结了一些植物释放异戊二烯等大量碳的潜在原因。在含氧的挥发性有机化合物中，包括异戊二烯氧化物，甲基丙烯醛和甲基乙烯基酮在内的某些化合物是双向交换的，并且大气化学反应和叶片在氧化应激下的反应都被认为是双向挥发性有机化合物的交换。已经开发了自下而上的基于过程的模型和自上而下的逆模型来估计全球和局部萜类化合物的排放。为了验证模型的准确性和精确性，需要在各个位置收集其他原位地面真实数据，例如长期磁通量测量数据。否则，与CO相比，这些模型可能仍存在较大的不确定性_2个磁通量模型可以通过大量地面真实磁通量数据进行验证。