Understanding how ozone impacts plant water-use efficiency

This scientific commentary refer to ‘Combining carbon and oxygen isotopic signatures to identify ozone-induced declines in tree water-use efficiency’ by Li et al. (doi: 10.1093/treephys/tpab041). Ozone (O3) in the troposphere is an important air pollutant that causes adverse effects on plants and ecosystems worldwide (Ainsworth et al. 2012, Grulke and Heath 2020). Tropospheric O3 occurs in the atmosphere naturally through the photochemical reactions of O3 precursors: nitrogen oxides (NOx), volatile organic compounds (VOCs), methane (CH4) and carbon monoxide (CO). The abundance of these O3 precursors can be elevated due to anthropogenic activities, for example chemical emissions from vehicles, industrial processes and biomass burning (Ainsworth et al. 2020). On average, the surface [O3] has more than doubled since 1850 due to rapid global industrialization and urbanization (Monks et al. 2015, Ainsworth...