To reduce the impact of differences in physical properties and spectral reflectance of urban features in multi-temporal remote sensing images on urban remote sensing mon-itoring accuracy,we propose a new automatic threshold urban index model. Through qualitative and quantitative verifica-tion,the overall accuracy of the index model is 16.54％ high-er than that of the typical city index model,and the Kappa co-efficient is 0.86. We establish a remote sensing monitoring of the spatio-temporal changes on Hefei urban area from 2000 to 2021 with this index model,analyze the characteristics of ur-ban sprawl year by year,and reveal the spatio-temporal change characteristics of 5-year intervals. The urban expan-sion of Hefei urban area increased by 376.7 km2(2000—2021),which experienced four development periods. The ur-ban spatial changes are mainly concentrated in the west,south,northeast and southwest of Hefei. The expansion of Hefei urban area is positively correlated with GDP and popula-tion growth,with correlation coefficients of 0.93 and 0.92,respectively.
维普
万方数据