Abstract: To study the effect of wetlands on urban air quality, air temperature, humidity, and negative oxygen ion concentration were monitored along transects from wetland to surrounding landscapes in eight typical wetlands of Beijing. The observed results showed that air temperature increased (R²≥0.81, P<0.01) while humidity and negative oxygen ion concentration decreased (R²≥0.83, P<0.01) with increasing the distance from wetlands. At locations 5 km away from the wetlands, air temperature was 4.4 SymbolpB@C higher, while humidity and negative oxygen ion concentration were 12.8% and 27.2% lower than the values above the wetlands. Moreover, lakes depressed air temperature and elevated air humidity of local environment more pronounced than rivers, by about 1 SymbolpB@C and 5%, respectively. These results demonstrated that urban wetlands had the potential to improve local air quality. Therefore, it was suggested to construct more wetlands with appropriate types to make best use of the integrated functions of urban wetlands.

Key words: possibility, vulnerability, forest fire, climate change, risk assessment