[1] Chinese Acad Surveying & Mapping, Beijing 100830, Peoples R China
[2] China Univ Min & Technol, Sch Environm & Spatial Informat, Key Lab Land Environm & Disaster Monitoring, MNR, Xuzhou 221116, Peoples R China
[3] Hebei Nat Resources Arch, Shijiazhuang 071299, Peoples R China
[4] East China Normal Univ, Shanghai 200241, Peoples R China