The evaluation of isoprene diffusion and emission processes from Quercus serrate forest

异戊二烯是最丰富的生物源性挥发性有机化合物。我们使用自动室系统和质子转移反应质谱仪来检测三种栎属植物夜间释放的异戊二烯。日落后排放率最高，到黎明排放率逐渐降低。它与温度呈线性关系。在干旱条件下，上冠层比下冠层要高。此外，森林周围异戊二烯浓度的空间变化表明异戊二烯作为示踪剂对森林空气扩散过程的追踪是有效的。由于全球变暖可能增加全球范围内夜间异戊二烯的排放，本研究确定需要进一步研究干旱和热应激下夜间异戊二烯的排放。

Isoprene is the most abundant species of biogenic volatile organic compound. We used an automated chamber system and a proton-transfer-reaction mass spectrometer to detect nocturnal emissions of isoprene from three Quercus species. The rate of emission was greatest after sunset and decreased till dawn. It showed a linear relationship with temperature. It was higher in the upper canopy than in the lower canopy, and was higher under drought. In addition, spatial variation of isoprene concentration around forest shows the effectiveness of isoprene as a tracer to trace the diffusion process of the forest air. As global warming could increase nocturnal isoprene emissions worldwide, this study identifies the need for further study of nocturnal isoprene emissions under drought and heat stress.