行道树在城区绿化中具有重要的作用。但是由于城市中各种人为活动干扰的结果,城市行道树的生存条件十分恶劣。就北京城区而言,行道树多植于贫瘠的城市渣土上,土壤理化性状不良;人流量大造成土壤密实;街道路面铺装阻碍透气透水;地下构筑物使根系的生存空间 Road trees in the urban greening has an important role. However, due to the disturbance of various man-made activities in the city, the survival conditions of urban roadside trees are very poor. In terms of urban areas in Beijing, most of the street trees are planted on poor urban dregs with poor physical and chemical properties of the soil; densely populated areas result in dense soils; street paving hinders ventilation and water permeation; underground structures make the root living space