Fig. 1

Topographic Elevation Map of Subzone 01, Beijing Urban Sub-center(Created Using ArcGIS Desktop 10 Simplified Chinese Edition; URL: https://www.esri.com/en-us/home).

Topographic Elevation Map of Subzone 01, Beijing Urban Sub-center(Created Using ArcGIS Desktop 10 Simplified Chinese Edition; URL: https://www.esri.com/en-us/home).