Land subsidence in Beijing, China, 1955-2010

Wednesday, 17 December 2014
Zhaoqin Gu, Huili Gong, Youquan Zhang, Xuehui Lu and Huanhuan Liu, CNU Capital Nornal University, Beijing, China
Long-term over-exploitation of groundwater since the middle of 1950’s and heavy exploitation of surface water in emergency water source since 2001 has caused severe infrastructure destruction and incalculable economic losses in Beijing plain area of China. The maximum of subsidence could reach 1233mm over 60 years. Subsidence integrated monitoring system in this study, based on interferometric synthetic aperture radar (InSAR), leveling network, multilevel monitoring wells and extensometer borehole, was applied to qualitative and quantitative the occurrence, development and evolution of subsidence, which will be helpful to characterize the mechanism of subsidence and predict the future subsidence trend. The monitored results showed subsidence was distributed through most parts of the plain area and formed a broad plain-wide bowl for the period 1955-2010. The maximum accumulated subsidence of five primary localized subsidence bowls-northwest, north, central, south, southwest bowl- recognized in the plain were 700 mm, 1233 mm, 1058 mm, 961 mm, 1030 mm, respectively. Range of subsidence area has expanded outward from urban area to suburban area. The subsidence rates of these subsidence bowls are between 10 mm/yr to 60 mm/yr. Most records show the subsidence rates for the period of 2000-1010 is faster than that of 1955-2000, which indicates land subsidence in Beijing plain area of China has been undergoing rapid development at present.

Keywords Land Subsidence • Beijing • Groundwater • InSAR • Mechanism