Grote R, Niinemets U
Research Center Karlsruhe GmbH, Institute for Meteorology and Climate Research, Atmospheric Environmental Research (IMK-IFU), Kreuzeckbahnstrasse 19, 82467 Garmisch-Partenkirchen, Germany.
Plant Biol (Stuttg). 2008 Jan;10(1):8-28. doi: 10.1055/s-2007-964975.
Accurate prediction of plant-generated volatile isoprenoid fluxes is necessary for reliable estimation of atmospheric ozone and aerosol formation potentials. In recent years, significant progress has been made in understanding the environmental and physiological controls on isoprenoid emission and in scaling these emissions to canopy and landscape levels. We summarize recent developments and compare different approaches for simulating volatile isoprenoid emission and scaling up to whole forest canopies with complex architecture. We show that the current developments in modeling volatile isoprenoid emissions are "split-ended" with simultaneous but separated efforts in fine-tuning the empirical emission algorithms and in constructing process-based models. In modeling volatile isoprenoid emissions, simplified leaf-level emission algorithms (Guenther algorithms) are highly successful, particularly after scaling these models up to whole regions, where the influences of different ecosystem types, ontogenetic stages, and variations in environmental conditions on emission rates and dynamics partly cancel out. However, recent experimental evidence indicates important environmental effects yet unconsidered and emphasize, the importance of a highly dynamic plant acclimation in space and time. This suggests that current parameterizations are unlikely to hold in a globally changing and dynamic environment. Therefore, long-term predictions using empirical algorithms are not necessarily reliable. We show that process-based models have large potential to capture the influence of changing environmental conditions, in particular if the leaf models are linked with physiologically based whole-plant models. This combination is also promising in considering the possible feedback impacts of emissions on plant physiological status such as mitigation of thermal and oxidative stresses by volatile isoprenoids. It might be further worth while to incorporate main features of these approaches in regional empirically-based emission estimations thereby merging the "split ends".
准确预测植物产生的挥发性异戊二烯通量对于可靠估计大气臭氧和气溶胶形成潜力至关重要。近年来，在理解异戊二烯排放的环境和生理控制以及将这些排放扩展到冠层和景观尺度方面取得了重大进展。我们总结了近期的进展，并比较了模拟挥发性异戊二烯排放以及扩展到具有复杂结构的整个森林冠层的不同方法。我们表明，目前在挥发性异戊二烯排放建模方面的进展是“两头并进”的，即在微调经验排放算法和构建基于过程的模型方面同时但又分开进行努力。在挥发性异戊二烯排放建模中，简化的叶级排放算法（圭恩特算法）非常成功，特别是在将这些模型扩展到整个区域后，不同生态系统类型、个体发育阶段以及环境条件变化对排放速率和动态的影响在一定程度上相互抵消。然而，最近的实验证据表明存在尚未考虑的重要环境影响，并强调了植物在空间和时间上高度动态适应的重要性。这表明当前的参数化在全球变化和动态的环境中不太可能适用。因此，使用经验算法进行长期预测不一定可靠。我们表明，基于过程的模型有很大潜力捕捉不断变化的环境条件的影响，特别是如果叶模型与基于生理的全株模型相联系。这种结合在考虑排放对植物生理状态的可能反馈影响方面也很有前景，例如挥发性异戊二烯对热应激和氧化应激的缓解作用。将这些方法的主要特征纳入基于区域经验的排放估计中从而合并“两端”可能更有价值。
