Study on Transpiration Water Consumption and Photosynthetic Characteristics of Landscape Tree Species under Ozone Stress

Using Pinus bungeana, Platycladus orientalis, Koelreuteria paniculata and Ginkgo biloba as research objects, three open-top chambers with different ozone-concentration gradients were set up (NF, NF40 NF80) based on trunk sap-flow technology to study the difference in ozone absorption by trees under concentrations. The results showed that monthly diurnal variations of density tree species decreased increase concentration, concentration reduced water consumption, uptake rate (FO3), net photosynthetic (Pn) water-use efficiency (WUE) species. density, FO3 WUE higher than those bungeana orientalis significantly at concentrations NF80; compared NF, sap flow 1.04 1.03 times much respectively; consumption 1.82 1.56 decline was 1.30 1.52 1.64 respectively. have stronger tolerance ozone, while weak. A variety conifers can be planted areas serious pollution.