## 2 Materials and Methods
### Calculation of Cumulative Photosynthetic CO\({}_{2}\) Uptake  
The cumulative photosynthetic CO\({}_{2}\) uptake per unit LA (mol CO\({}_{2}\) m\({}^{-2}\) LA s\({}^{-1}\)) during each growing season was calculated as the sum of the product of time (1 h) and estimated hourly value of net photosynthetic rate (\(P_{\text{n\_est}}\), \(\upmu\)mol CO\({}_{2}\) m\({}^{-2}\) LA s\({}^{-1}\)) over one growing season (\(\Sigma P_{\text{n\_est}}\), mol CO\({}_{2}\) m\({}^{-2}\) LA). The \(P_{\text{n\_est}}\) was calculated from the hourly mean PPFD monitored inside the OTCs and the \(A\)-light curves that were obtained monthly. The PPFD was the mean value of the 12 OTCs. The \(A\)-light curves were the means of the three chamber replicates for each treatment. When the hourly mean of PPFD was 0 \(\upmu\)mol m\({}^{-2}\) s\({}^{-1}\), \(P_{\text{n\_est}}\) was not calculated and was not summed up for the \(\Sigma P_{\text{n\_est}}\). The calculation period was from the first to the last measurement days of the \(A\)-light curve for each growing season. In each growing season, the \(A\)-light curve obtained from the first measurement was used to calculate \(P_{\text{n\_est}}\) during the period from the first measurement day to the middle day of the subsequent measurement day. The \(A\)-light curve obtained from the last measurement was used to calculate \(P_{\text{n\_est}}\) during the period from the middle day of the previous measurement day to the last measurement day. The \(A\)-light curves, other than those obtained from the first and last measurements in each growing season, were used to calculate \(P_{\text{n\_est}}\) from the middle day of the previous measurement day to the middle day of the subsequent measurement day (approximately 1 month). This calculation assumed the step-changes in the \(A\)-light curve between the two measurement days. Because the \(\Sigma P_{\text{n\_est}}\)is time integral of \(P_{\text{n\_est}}\), \(\Sigma P_{\text{n\_est}}\) calculated by assuming linear changes in \(A\)-light curve between the two measurement days would result in the same value. When there was no target leaf owing to O\({}_{3}\)-induced early leaf abscission (e.g., Tables S6 and S7), we did not accumulate the \(P_{\text{n\_est}}\) for \(\Sigma P_{\text{n\_est}}\). The monthly \(A\)-light curves of each species are shown in Table S6. The sums of the product of the number of day and the \(A_{\text{sat}}\) at PPFD of 1500 \(\upmu\)mol m\({}^{-2}\) s\({}^{-1}\) (\(\upmu\)mol CO\({}_{2}\) m\({}^{-2}\) LA s\({}^{-1}\)) over one growing season (\(\Sigma A_{\text{sat}}\times\) days, \(\upmu\)mol CO\({}_{2}\) m\({}^{-2}\) LA s\({}^{-1}\) day) were calculated for each treatment and each growing season as a possible indicator of O\({}_{3}\)-induced percent changes in \(\Sigma P_{\text{n\_est}}\). The \(A_{\text{sat}}\), which was recorded when the \(A\)-light curve was measured and the number of days during the growing season were used to calculate \(\Sigma A_{\text{sat}}\times\) days. The periods for the \(\Sigma A_{\text{sat}}\times\) days was the same as those for the \(\Sigma P_{\text{n\_est}}\). The \(A_{\text{sat}}\) measured on the first measurement day was multiplied by the number of days during the period from the first measurement day to the middle of the subsequent measurement day. The \(A_{\text{sat}}\) that was measured on the last measurement day was multiplied by the number of days during the period from the last measurement day to the middle of the previous measurement day. The \(A_{\text{sat}}\), other than those measured on the first and last measurement days, were multiplied by the number of days from the middle day of the previous measurement to that of the subsequent measurement (approximately 1 month). The products of the \(A_{\text{sat}}\) and the number of days were summed for \(\Sigma A_{\text{sat}}\times\) days during each growing season. The monthly \(A_{\text{sat}}\) are shown in Table S7. The \(\Sigma P_{\text{n\_est}}\) and \(\Sigma A_{\text{sat}}\times\) days in the leaves of _F. crenata_, _Q.