Objective: To study the changes of growth, physiological and absorption characteristics of Pinus bungeana under ozone (O₃) stress, to elucidate the correlations among the indicators, and to determine its degree of response to O₃. Methods: The growth, physiological characteristics and O₃ uptake capacity of Pinus bungeana seedlings were measured in an open-top O₃ fumigation manual control experiment with three concentration gradients (NF: normal atmospheric O₃ concentration, NF40: normal atmospheric O₃ concentration plus 40 nmlol/mol; NF80: normal atmospheric O₃ concentration plus 80 nmol/mol), and the relationships between the characteristics of Pinus bungeana under different O₃ concentrations were investigated with correlation analysis, redundancy analysis and analysis of variance. Results: (1) Plant height growth (ΔH), diameter growth at 50 cm (ΔDBH), stomatal size (S), stomatal density (M), stomatal opening (K), stomatal conductance (G_s), net photosynthetic rate (P_n), transpiration rate (E_t), water use efficiency (WUE), maximum photochemical efficiency (F_v/F_m), chlorophyll content (CHL), whole tree water consumption (W), and O₃ uptake rate () all decreased with the increase of O₃ concentration; while intercellular CO₂ concentration () and relative conductivity (L) increased with the increase of O₃ concentration; (2) growth indicators of Pinus bungeana under O₃ stress (ΔH, ΔDBH) were the most correlated with O₃ uptake status (, W), followed by photosynthetic indicators (, WUE, ,, ) and growth indicators (ΔH, ΔDBH) and stomatal characteristics (K, M, S) under O₃ stress, some physiological indicators (L, ) were relatively weakly correlated with photosynthesis (, WUE,,, ) and stomatal (K, M, S); (3) all the indicators of Pinus bungeana were significantly different under O₃ treatments of NF and NF80 (P < 0.05), ΔH, ΔDBH, M, CHL, , , W and were most significantly different under NF and NF40 treatments, and K, S, WUE, , , , L were more significantly different under NF40 and NF80 treatments. Conclusion: The experiment proved that the growth of Pinus bungeana was slowed, photosynthetic capacity was reduced, and the absorption capacity of O₃ was further reduced by long-term exposure to high concentration of O₃. The growth of Pinus bungeana was most correlated with the changes of O₃ absorption characteristics, and the stomatal characteristics were most correlated with photosynthetic physiological characteristics, and the reduction of photosynthetic capacity etc. further led to the curtailment of its growth.

1. Ainsworth EA, Lemonnier P, Wedow JM. The influence of rising tropospheric carbon dioxide and ozone on plant productivity. Plant Biology 2020; 22(Suppl.1): 5–11.

2. Wang T, Xue L, Brimblecombe P, et al. Ozone pollution in China: A review of concentrations, meteorological influences, chemical precursors, and effects. Science of the Total Environment 2017; 575: 1582–1596.

3. Ma J, Chu B, Liu J, et al. NOx promotion of SO2 conversion to sulfate: An important mechanism for the occurrence of heavy haze during winter in Beijing. Environmental Pollution 2018; 233: 662–669.

4. Yang Y, Liu X, Qu Y, et al. Formation mechanism of continuous extreme haze episodes in the megacity Beijing, China, in January 2013. Atmospheric Research 2015; 155: 192–203.

5. Ministry of Ecology and Environment of the People’s Republic of China. Report on the state of the ecology and environment in China 2019. Beijing: Ministry of Ecology and Environment of the People’s Republic of China; 2020.

6. Li K, Jacob DJ, Liao H, et Al. Anthropogenic drivers of 2013–2017 trends in summer surface ozone in China. Proceedings of the National Academy of Sciences 2019; 116(2): 422–427.

7. Beijing Municipal Ecological and Environment Bureau. Beijing Environmental Statement 2013. Beijing: Beijing Municipal Ecological and Environment Bureau; 2014.

8. Beijing Municipal Ecological and Environment Bureau. Beijing Environmental Statement 2015. Beijing: Beijing Municipal Ecological and Environment Bureau; 2016.

9. Beijing Municipal Ecological and Environment Bureau. Beijing Ecology and Environment Statement 2019. Beijing: Beijing Municipal Ecological and Environment Bureau; 2020.

10. Galant A, Koester RP, Ainsworth EA, et al. From climate change to molecular response: Redox proteomics of ozone-induced responses in soybean. New Phytologist 2012; 194(1): 220–229.

11. Wilkinson S, Mills G, Illidge R, et al. How is ozone pollution reducing our food supply. Journal of Experimental Botany 2012; 63(2): 527–536.

12. Yamaguchi M, Watanabe M, Matsumura H, et al. Experimental studies on the effects of ozone on growth and photosynthetic activity of Japanese forest tree species. Asian Journal of Atmospheric Environment 2011; 5(2): 65–78.

13. Agathokleous E, Saitanis CJ, Wang XN, et al. A review study on past 40 years of research on effects of tropospheric O3 on belowground structure, functioning, and processes of trees: A linkage with potential ecological implications. Water, Air & Soil Pollution 2016; 227(1): 1–28.

14. Schaub M, Skelly JM, Zhang JW, et al. Physiological and foliar symptom response in the crowns of Prunus serotina, Fraxinus americana and Acer rubrum canopy trees to ambient ozone under forest conditions. Environmental Pollution 2005; 133(3): 553–567.

15. Wan W, Xia Y, Zhang H, et al. The ambient ozone pollution and foliar injury of the sensitive woody plants in Beijing exurban region. Acta Ecologica Sinica 2013; 33(4): 1098–1105.

16. Galloway JN, Townsend AR, Erisman JW, et al. Transformation of the nitrogen cycle: Recent trends, questions, and potential solutions. Science 2008; 320(5878): 889–892.

17. Li P, Feng Z, Shang B, et al. Stomatal characteristics and ozone dose-response relationships for six greening tree species. Acta Ecologica Sinica 2018; 38(8): 2710–2721.

18. Chen B, Li S, Lu S. Ozone uptake characteristics in different dominance hierarchies of poplar plantation. Journal of Beijing Forestry University 2015; 37(7): 29–36.

19. Niu J. Effects of elevated ozone and nitrogen deposition on the growth and physiology of Ci nnamomum camphora seedlings [PhD thesis]. Beijing: Chinese Academy of Sciences; 2012.

20. Zhu J, Xu C, Qin G, et al. Responses of leaf functional characters of three typical greening plants to air pollution and leaf economic spectrum analysis: A Beijing city as the study case. Journal of Central South University of Forestry & Technology 2019; 39(3): 91–98.

21. Hoshika Y, Carriero G, Feng ZZ, et al. Determinants of stomatal sluggishness in ozone-exposed deciduous tree species. Science of the Total Environment 2014; 481: 453–458.

22. Hoshika Y, Omasa K, Paoletti E. Both ozone exposure and soil water stress are able to induce stomatal sluggishness. Environmental and Experimental Botany 2013; 88 (Suppl.1): 19–23.

23. Paoletti E, Grulke NE. Ozone exposure and stomatal sluggishness in different plant physiognomic classes. Environmental Pollution 2010; 158(8): 2664–2671.

24. Cao X, Run L. The exploration of the purification of automobile exhausts contamination by plants. Journal of Central South University of Forestry & Technology 2007; 27(2): 133–136.

25. Pang J, Kobayashi K, Zhu JG. Yield and photosynthetic characteristics of flag leaves in Chinese rice (Oryza sativa) varieties subjected to free-air release of ozone. Agriculture, Ecosystems and Environment 2009; 132(3): 203–211.

26. Feng ZZ, Kobayashi K, Ainsworth E. Impact of elevated ozone concentration on growth, physiology, and yield of wheat (Triticum aestivum). Global Change Biology 2008; 14: 2696–2708.

27. Calatayud A, Barreno E. Response to ozone in two lettuce varieties on chlorophyll a fluorescence, photosynthetic pigments and lipid peroxidation. Plant Physiology and Biochemistry 2004; 42(6): 549–555.

28. Xin Y, Shang B, Chen X, et al. Effects of elevated ozone and nitrogen deposition on photosynthetic characteristics and biomass of Populus cathayana. Environmental Science 2016; 37(9): 3642–3649.

29. Feng Z, Li P, Yuan X, et al. Progress in ecological and environmental effects of ground-level O3 in China. Acta Ecologica Sinica 2018; 38(5): 1530–1541.

30. Liu D, Zhao S, Wang X, et al. The effect of ozone on the leaf damages symptom and physiological characteristics of landscape plants. Zhang Q (editor). China Ornamental Horticulture Symposium 2015; 2015 Aug 18–20; Fujian, Xiamen. Beijing: China Forestry Publishing House; 2015. p. 507–512.

31. Zhang W. Effects of elevated O3 level on the native tree species in subtropical China [PhD thesis]. Beijing: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences; 2011.