The contradiction between continuous decease of Chinese urban land and increase of polulation drive urban space to develop in intensivism and expand to three-dimensional space.

• 我国城市建设迅速发展，而建设用地随着人口的不断增加持续减少，这一矛盾在日益加剧，迫使城市空间向集约式、“三维式”方向发展。