Quantifying Land Use/Land Cover Change and Urban Expansion in Dongguan, China, From 1987 to 2020

Dongguan has experienced the most rapid urbanization since the Chinese reform and opening policy. To analyze the urban expansion in this city, in this study, 12 land use/land cover maps were produced using a multiple classifiers system on the Google Earth Engine platform. A long time-series land use dataset from 1987 to 2020, was achieved. The results indicate that, during the past 33 years, the urban area increased by 13.84 times and reached 1483.06 km(2) in 2020, whereas cultivated land and forest continually decreased because of rapid urbanization. By analyzing the changes in urban forms and landscape indexes, Dongguan experienced a diffusion-coalescence-diffusion phase, and its urban expansion can be divided into three stages: The early-age urbanization stage (1987-1996), the rapid urbanization stage (1996-2011), and the intensive urbanization stage (2011-2020). The development of the economic and dual-level administration of Dongguan expanded the urban area surrounding the towns and traffic corridors, and, finally, formed a connected urban area. The urban expansion, just like sparking spots firing the prairie, is special and conforms to a Dongguan urbanization pattern.