Evaluation of the Impact of Urbanization Factors on Land Subsidence by GWR

Land subsidence has been observed in many cities with rapid urban expansion. Most studies have qualitative analyses of the influencing factors on land subsidence, such as the exploitation of groundwater and mineral resources. Few studies have quantitatively analyzed the spatial heterogeneity between land subsidence and urbanization. In this paper, the LiCSBAS (small baseline subset with the LiCSAR) method was employed to map the land subsidence rate in the central area of Chengdu from 2016 to 2018. Then geographically weighted regression (GWR) model was utilized to study the spatial variation relationship between ground subsidence and urbanization factors. The results show that the land subsidence rate in the study area ranges from -12.21 to 13.8 mm/yr., with a mean value of -0.09 mm/yr. The land subsidence is relatively stable, with no significant subsidence funnel. The GWR findings demonstrate that urbanization factors have different degrees of influence on land subsidence. Large trading areas and business facilities have the greatest influence, followed by residential areas and metro lines. This paper provides a novel and effective way to quantitatively study the spatial heterogeneity between land subsidence and urbanization and provides theoretical support for urban design and planning.