Land Subsidence and Uplift Surveying by Synthetic Aperture Radar Interferometry in Lianjiang Plain

Understanding the Spatiotemporal Characteristics of Land Subsidence and Rebound in the Lianjiang Plain Using Time-Series InSAR with Dual-Track Sentinel-1 Data

“…Additionally, the maximum uplift was found in Puning (S1), occurring in agreement with the location of previous studies [38,39], while the peak uplift rate of +48 mm/year in this work differs from those, in which the uplift rate was over +100 mm/year and +20 mm/year, respectively. There are two possible reasons for the discrepancy in the observed peak subsidence and uplift rate: (1) different methods were employed to detect measurement points and estimate annual rates, such that more measurement points were detected in Liu et al [13]; Du et al [37] have greater subsidence due to longer wavelength compared to the band used in this study; (2) different observation periods contributed to different annual rates, and annual rates in Zhang et al [38] are hence much higher than the average annual rates according to Huang et al [39] and this study. In additional, Zhang et al [38] and Huang et al [40] noted the trend of stability for Chaoyang (S3), once a severe subsidence area, which is not consistent with the result of this study.…”

“…In addition, these studies have revealed the influence of structural geology, land use, and faults on land subsidence [13,37]. Subsequent land subsidence was also observed by Zhang et al [38]. In particular, two obvious land uplift zones in the northern part of the plain were detected.…”

“…There are two possible reasons for the discrepancy in the observed peak subsidence and uplift rate: (1) different methods were employed to detect measurement points and estimate annual rates, such that more measurement points were detected in Liu et al [13]; Du et al [37] have greater subsidence due to longer wavelength compared to the band used in this study; (2) different observation periods contributed to different annual rates, and annual rates in Zhang et al [38] are hence much higher than the average annual rates according to Huang et al [39] and this study. In additional, Zhang et al [38] and Huang et al [40] noted the trend of stability for Chaoyang (S3), once a severe subsidence area, which is not consistent with the result of this study. The magnitude of the deformation Chaoyang (S3) varies from period to period, which could indicate temporal variation in deformation rates.…”