[Progress in the Interactions of Ozone Pollution and Other Environmental Stress on Urban Forests in China]

Ground-level ozone pollution(O₃) and climate change have become key global problems threatening the environment and sustainable development of urban forests. At present, various studies have assessed the O₃ impacts on trees; however, it is difficult to accurately evaluate the complex ecological effects caused by multiple factors on the natural urban environment. In this paper, the interactions between O₃ and carbon dioxide(CO₂), drought, nitrogen deposition, and warming, as well as the effects of the physiology, biochemistry, and growth of urban trees in China were reviewed. Elevated CO₂ could alleviate the negative effects of elevated O₃ on the photosynthetic metabolism, antioxidant system, and growth of trees. There is a complex interaction between O₃ and drought, which may synergistically aggravate, alleviate, or have no effect on trees. However, there was no correlation between O₃ and N deposition, only a significant interaction between elevated temperatures and O₃, which slowed down the adverse effects of O₃ on tree growth and photosynthesis. Finally, suggestions are put forward to manage and sustainable develop urban forests in China under future climate change and air pollution.