The First Seasonal Snowfall Impacts Plant Photosynthesis and Monoterpene Emissions

Abstract

AbstractBiogenic monoterpene emissions impact regional and global atmospheric chemistry. The impact of temperature fluctuations on emissions is well‐understood, but the role of weather events is not. Here, we simultaneously measure photosynthesis and speciated monoterpene emissions from leaves of one cultivar of Liriodendron tulipifera prior to, during, and following the first seasonal snow event. During snow, leaves act as a sink to atmospheric monoterpenes and release a burst of monoterpenes the following day—an order of magnitude higher than pre‐snow emission rates. As senescence continues, the characteristic profile of the emissions changes in favor of β‐ocimene. While summed monoterpene emission decreases throughout senescence, the enhanced β‐ocimene emission increases hydroxyl radical reactivity compared to pre‐snow conditions. Our findings highlight the importance of speciated monoterpene measurements in considering biosphere‐atmosphere exchange of biogenic hydrocarbons.