Tracking spatial–temporal landscape changes of impervious surface areas, bare lands, and inundation areas in China during 2001–2017

Efficient and timely quantification of landscape changes of urbanization, devegetation, and inundation in China is important for decision making in sustainable development. This study proposed a novel and automatic approach to track landscape changes in China based on 500 m 8-day composite MODIS datasets from 2001 to 2017. An overall accuracy of 94.09% was achieved on the basis of 5,178 references sites. Results showed that newly impervious surface areas (ISA), bare lands, and inundated water bodies accounted for 0.51%, 0.23%, and 0.25% of the total land area in China, respectively. Rapid urbanization transformation was observed with the average annual land urbanization rate of 9.53%, almost three-times higher than the global rate of urbanization. The speediest period of urbanization was exhibited in 2009 and 4,938.89 km² of newly formed ISA were generated in this single year. The most obvious period of devegetation, which converted vegetation to bare lands, was observed from 2006 to 2009, with 2000–2100 km² yr⁻¹. Urbanization and devegetation dominantly occurred in humid/semihumid regions (>85%), particularly in the Yangtze River Delta. The remarkable devegetation was strongly associated with newly ISA; however, significant reduction of devegetation was observed in arid/semiarid regions in 2010s. Besides one hotspot surrounding newly ISA, the other hotspot of inundation in remote highlands was highlighted and distinct reduction in inundation was evidenced after 2010. A free download link for these datasets is attached (https://drive.google.com/drive/folders/1ZGSk3sP04ob77lmLTH01B0x1PEgjby7w?usp=sharing).