Phase consistency is a critical prerequisite for achieving high-precision time-series InSAR deformation retrieval. However, conventional SBAS-InSAR methods provide only limited consideration of phase consistency during the inversion process. Within the SBAS-InSAR workflow, two principal categories of error sources are primarily responsible for phase inconsistency, manifested as non-zero closure phase (NCP): (1) fading biases introduced during multilooking and filtering prior to phase unwrapping; and (2) unwrapping errors caused by large deformation gradients, low coherence, or inappropriate selection of unwrapping algorithms. To address these issues, this study introduces an improved SBAS-InSAR processing workflow, termed NCP-SBAS, designed to improve the accuracy of deformation field estimation and thereby enhance its applicability to geological hazard monitoring. The key idea of the method is to enforce phase consistency as a constraint, jointly accounting for the spatiotemporal characteristics of fading biases and the valid deformation signals, thereby enabling effective correction of NCP. To evaluate the effectiveness of NCP-SBAS, this study conducted a detailed analysis of deformation differences in Hualong County, Qinghai Province, before and after NCP correction, highlighting the significant advantages of the proposed approach. The results indicate that the influence of fading biases on deformation estimates depends on both the magnitude and direction of deformation, while unwrapping errors primarily lead to an underestimation of deformation. In addition, the study provides an in-depth discussion of how fading biases and unwrapping errors affect landslide monitoring and identification.

The Yuanjiang Basin in Northwestern Hunan is a landslide-prone region due to its complex geological features and dense vegetation. Conventional single-polarization muti-temporal InSAR (MT-InSAR) methods often fail in such areas because of severe decorrelation, leading to reduced accuracy and coverage in monitoring. To address these limitations, this study proposes an innovative landslide detection framework using the muti-temporal polarimetric InSAR (MT-PolInSAR) method. This approach improves the density and precision of deformation measurements by optimizing polarimetric and temporal dimensions. Leveraging fully polarimetric ALOS-2 data acquired from May 2021 to June 2022, 32 potential deformation sites were identified, including 18 landslide-prone areas and 8 sites showing other deformation types, with average deformation rates between −4 and −2 cm/year. Field validation confirmed an identification accuracy of 81.25%, demonstrating the robustness of fully polarimetric long-wavelength SAR data for landslide monitoring in densely vegetated regions. This method offers a significant advancement in the detection and assessment of landslide hazards in challenging environments.

This study is based on pollution assessment system and sustainability under a high geological background. The findings from atmospheric deposition research indicate that the exceedance rates for Cd, As, and Hg elements in black shale are 408%, 141%, and 220%, respectively. In atmospheric deposition, the concentrations of Cd, Hg, and Pb exceed the background values by 2.83, 3.29, and 4.08 times in dry conditions and by 3.6, 4.07, and 3.43 times in wet conditions. The difference between dry and wet deposition primarily reflects the concentration variations of Cd, Hg, and As. The distribution of Cd concentrations exceeding standards is widespread, covering over 71% of the total area, and shows a negative correlation with the enrichment patterns in weathered soils. Source analysis indicates that the contribution rates of PC1 for dry and wet deposition are 84.1% and 80.5%, respectively. This finding reveals that atmospheric deposition is significantly influenced by natural weathering processes, while anthropogenic factors exacerbate the overall pollution levels. The HI values for As, Hg, Pb, and Cr for both adults and children are all greater than 1, with the HI value for Pb in dry deposition reaching 13.5, indicating it poses the most severe health risk to children’s safety.