城市环境的绿化美化是现代化城市建设中的重要内容之一，绿化美化的程度，是城市建设水平和文明程度的象征．随着城市现代化建设的不断发展，城市人口的不断增加，需求的绿地面积也越来越大。在有限的城市规模中，除了必须认真搞好地面绿化外，增辟绿化空间，建设一个多层次的 The beautification of the urban environment is an important part of the modern urban construction. The degree of afforestation and beautification is a symbol of the level of urban construction and the degree of civilization. With the continuous development of urban modernization and the continuous increase of urban population, the area of ​​green space required is also growing. In a limited urban area, in addition to the need to conscientiously do a good job of greening the ground, green space should be added to build a multi-level