Effect of different plant communities on NO2 in an urban road greenbelt in Nanjing, China

Abstract

As an important part of urban ecosystems, plants can reduce NO2 concentrations in the air. However, there is little evidence of the effects of different plant communities on NO2 concentrations in street-scale green spaces. We used a multifunctional lifting environmental detector to investigate the impact of environmental factors and small plant communities on NO2 concentrations in street green spaces during the summer and winter in Nanjing, China. The results showed that temperature, atmospheric pressure, and noise were significantly (P < 0.05) correlated with seasonal changes, temperature and humidity significantly (P < 0.01) influenced NO2 concentrations in winter and summer, and the average NO2 concentration in summer was generally higher than in winter. By comparing NO2 concentrations in different plant community structures and their internal spaces, we found that the plant community structure with tree-shrub-grass was more effective in reducing pollution. These findings will help predict the impact of plant communities on NO2 concentrations in urban streets and help city managers and planners effectively reduce NO2 pollution.