Abstract: The Beijing-Tianjin-Hebei(BTH) region is one of the most important and fastest-growing urban agglomerations in China. By capturing the dynamic changes of urban land and population in the region and their relationship, adjusting and optimizing the urban layout and spatial structure, and rational allocation of urban land resources are of great significance to the sustainable development of this region. Based on time series of Landsat images, this study uses the Google Earth Engine cloud platform to extract built-up land in the Beijing-Tianjin-Hebei region, and integrates the results with GlobeLand30, GHS-Built, GAIA and GLC_FCS-2020 land cover products to derive the built-up land data set during the period 2000-2020 in the region. An overall accuracy higher than 90% was obtained. Based on this data set, the urban functional boundaries were extracted, and the SDG 11.3.1 indicators-land consumption rate(LCR), population growth rate(PGR) and ratio of land consumption rate to population growth rate(LCRPGR) were calculated for each city. The results show that the overall LCRPGR value in the BTH region fluctuated from 1.142 in 2000-2005 to 0.946 in 2005-2010, 2.232 in 2010-2015, and 1.538 in 2015-2020. The change trend of LCRPGR value for cities with different population sizes is different. The LCRPGR values of small and medium-sized cities increased gradually, and the land use efficiency was decreasing. The LCRPGR values of small cities are higher than that of other types of cities. This dataset can be used as the basic data for urban expansion analysis in the BTH region, and applied to the monitoring and assessment of relevant indicators of the sustainable development goals in the region.
Keywords: Beijing-Tianjin-Hebei region; built-up area; land use efficiency; SDG11; Google Earth Engine