The Effects of Dual Ozone and Drought Stresses on the Photosynthetic Properties of Acer rubrum and A. pictum

Ozone (O3) pollution is accompanied by drought stress, especially at high temperatures. Tree species in cities often face dual stresses from O3 and drought. In this study, Acer rubrum ‘Autumn Blaze’ A. pictum were used as test plants open-top-chambers (OTCs) to investigate the trees most tolerant increasing urban gardens. The results showed that induced a change rubrum’s leaf coloration green red. representation was more variable than of pictum. pigment content affected plant color difference, Chl Car contents both negatively correlated with L*. Under drought, changes net photosynthetic rate (Pn) transpiration (Tr) less stomatal conductance (Gs) sensitive higher effect which enhanced moderate (MD) conditions on Gs. Tr decreased significantly under mitigated stress limit value (Ls). displayed differential changes, resulting greater structural heterogeneity within garden landscape. saplings adjusted their parameters stresses, whereas played an antagonistic role protecting rubrum, suggesting can resist Our study suggests alternative tree for inclusion gardens exposed stresses.