Dynamics of land cover changes and driving forces in China’s drylands since the 1970 s

The land cover in China's drylands has undergone dramatic changes due to rapid economic development and ecological restoration; however, the long-term and detailed land cover and land use change (LCLUC) focus on this unique region remains inadequate. Based on a temporally continuous and spatially high-resolution ChinaCover dataset from 1975, as well as climatic and socioeconomic data, this study analyzed the spatiotemporal pattern of LCLUC in China's drylands over 45 years, revealed the land conversions in the secondary category and explored its major driving factors in different periods. The results show that the rate of LCLUC is accelerating, and the trajectory of LCLUC is slowly changing although stable land is dominant. There are complex conversions among land covers, with each type of change affecting an average of 12 other types, and the LCLUC in drylands was mainly determined by the mutual conversions among shrub, desert shrub, steppe, sparse grassland, built-up, upland, and barren land. Anthropogenic land has grown rapidly, especially in the ethnic autonomous regions of Xinjiang, Ningxia, and Inner Mongolia, while ecological restoration programs have led to significant growth of natural land in the remaining regions. The widespread rapid expansion of artificial surfaces, western growth of agricultural land and eastern recovery of woodland have been supported by the continued decline of grassland and unused land. LCLUC in China's drylands was more influenced by population in the 1980 s, while economic development had a stronger influence in the 1990 s. In the 2000 s and 2010 s, however, population and cultivation had a stronger influence. All drivers are backed by macro policies. It was observed that resolution has a significant impact on the LCLUC when the resolution increases from 30 m to 10 m. These findings provide decision support for sustainable policy making and further promote the exploration of complex human-land relationships in drylands.