Response of Ginkgo biloba growth and physiological traits to ozone stress

Ginkgo biloba, the main greening tree species in Beijing, was used to study the effects of elevated ozone (O-3) concentrations on physiology and ecology using an open-top air chamber (OTC). We set three O-3 concentration gradients (NF: normal atmospheric O-3 concentration; NF40: normal atmospheric O-3 concentration plus 40 nmol/mol; NF80: normal atmospheric O-3 concentration plus 80 nmol/mol). Based on the theoretical basis of the coupling of O-3 and transpiration through stomata, the O-3 uptake from the leaf surface of G. biloba was studied under artificial control. The results showed that with the O-3 concentration increased, the leaves of G. biloba were damaged, stomatal density, stomatal aperture, stomatal size, net photosynthetic rate, transpiration rate, stomatal conductance, and chlorophyll content decreased, while intercellular CO2 concentrations and relative conductivity increased. The monthly and daily variations in the liquid flow density of G. biloba decreased with the increase in O-3 concentration. Similarly, water consumption and the ozone uptake rate (F-O3) of G. biloba decreased with the increase in O-3 concentration: Water consumption by the entire tree under the NF40 and NF80 ozone concentrations decreased compared to NF, the rates of decline were 68.77% and 78.38%, respectively. The rates of F-O3 decrease were 15.48% and 31.04%, respectively.

Automated summary

This study investigates the effects of elevated ozone concentrations on the physiology and ecology of Ginkgo biloba trees in Beijing using an open-top air chamber. The results show that as the ozone concentration increases, the leaves of G. biloba are damaged and various physiological parameters are affected.