Fig 1.
Distribution map of county-level administrative toponyms with the time of being named from 1,000 years ago.
The dots represent data on county-level administrative toponyms with naming time from 1,000 years ago. The green dots represent county-level administrative toponyms being named for 1,000–1,499 years, blue dots those being named for 1,500–1,999 years, and red dots those being named for 2,000 years ago.
Fig 2.
Map of the case study areas.
Fig 3.
Generation and transmission mode of Geo-Informatic Tupu.
Fig 4.
Spatio-temporal evolution of county-level administrative toponyms in the Northeast China Plain since the Sui dynasty.
Fig 5.
Spatio-temporal evolution of county-level administrative toponyms in the North China Plain since the Sui dynasty.
Fig 6.
Spatio-temporal evolution of county-level administrative toponyms in the Yangtze Plain since the Sui dynasty.
Table 1.
Statistical characteristics of county-level administrative toponyms.
Fig 7.
Distribution characteristics of naming time of county-level administrative toponyms in 2010.
Table 2.
Distribution characteristics of naming types of county-level administrative toponyms in 2010.
Table 3.
Statistical characteristics of county-level administrative toponyms relevant to natural factors since the Sui dynasty.
Fig 8.
DEM data of the case study areas.
DEM data at a resolution of 30 m were provided by the RESDC.
Fig 9.
Spatial distribution of toponym density and county GDP of the Northeast China Plain.
The statistical data on China’s GDP in 2010 (Figs 8, 10, 12) were obtained from the RESDC.
Fig 10.
Spatial distribution of toponym density and county population density in the Northeast China Plain.
Population data at the county level (Figs 9, 11, 13) were obtained from the 6th Census of China (2010).
Fig 11.
Spatial distribution of toponym density and county GDP of the North China Plain.
Fig 12.
Spatial distribution of toponym density and county population density in the North China Plain.
Fig 13.
Spatial distribution of toponym density and county GDP of the Yangtze Plain.
Fig 14.
Spatial distribution of toponym density and county population density in the Yangtze Plain.
Table 4.
Correlation coefficients between county-level administrative toponym density and DEM, GDP, and population density.
Table 5.
Correlation coefficients between administrative toponym density and DEM, GDP, and population density.
Fig 15.
Trend chart of toponym, population, and temperature changes.
The temperature values in Fig 15 are the change values with the current temperature. For historical population data, we referred to the statistical data from the National Earth System Science Data Sharing Infrastructure, National Science & Technology Infrastructure of China, and made some adjustments.