Land subsidence (2004–2013) in Changzhou in Central Yangtze River delta revealed by MT-InSAR

Abstract

Land subsidence in Changzhou City in the central Yangtze River Delta of China poses a serious threat to the safety of the environment and infrastructures. Excessive groundwater withdrawal, rapid urbanisation and industrial activities contribute to land subsidence in this area. In this study, we used the multi-temporal InSAR (MT-InSAR) technique to describe the spatiotemporal characteristics of land subsidence in Changzhou. Twenty-five ENVISAT ASAR and 29 TerraSAR-X images acquired from 2004 to 2013 were used to determine the rate and temporal evolution of land subsidence. We used the ERA-Interim model instead of spatiotemporal filtering in traditional MT-InSAR to mitigate the atmospheric phase screen. The InSAR-derived results were evaluated by comparing data from three time series methods and different bands (C and X bands), and accuracy was validated through levelling surveys and GPS measurements. For three regions, a distinct subsidence pattern was observed in major industrial areas with a maximum subsidence rate of up to − 39.9 mm/year. We also characterised the spatiotemporal variations of land subsidence in major industrial areas in Changzhou. The deformation of large-scale man-made linear features, namely high-speed railways, highway networks and a bridge, was analysed. The spatiotemporal characteristics and possible reasons for the observed subsidence were discussed to provide a reference for future urban development planning in Changzhou.

Spatio-Temporal Characteristics of Land Subsidence and Driving Factors Analysis in Shenzhen

“…Regions in China, including the Yangtze River Delta [18], the Yellow River Delta [19][20][21], the Pearl River Delta [22,23], and North China Plain [24,25], are currently experiencing high rates of subsidence due to the combined influence of natural factors and human activities. Taking the research area of Shenzhen as an example: Xu, Feng [26] conducted a detailed analysis using the Small Baseline Subset (SBAS) Interferometric Synthetic Aperture Radar (InSAR) technique to investigate the land subsidence rates in the land reclamation areas of western Shenzhen.…”

Experimental study of land subsidence in response to groundwater withdrawal and recharge in Changping District of Beijing

“…Research on land subsidence has mainly focused on two aspects: land subsidence monitoring and land subsidence prediction. Land subsidence monitoring uses various techniques, such as interferometric synthetic aperture radar (InSAR) [15][16][17], leveling surveys, borehole extensometers [18,19] and GPS data [20,21] to characterize the spatial and temporal distribution of subsidence [22][23][24][25][26][27][28]. Land subsidence prediction uses statistical modeling, numerical simulation and artificial intelligence.…”