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Barchan dunes are common on Earth, Mars and Titan. Previous studies have shown that their formation, migration and evolution are influenced by the wind regime and other factors, but details vary among regions. Understanding barchan morphology and migration will both improve our understanding of dune geomorphology and provide a basis for describing the environmental conditions that affect the formation and development of these dunes on Earth and other planets. Here, we provide detailed measurements of barchan dune migration in China's Quruq Desert, in the lower reaches of the Tarim River. We monitored their migration direction and rate, and their morphological changes during migration, by comparing Google Earth images acquired in 2003 and 2014. The dunes migrated west‐southwest, close to the local resultant drift direction. The migration rate averaged 8.9 to 32.1 m year−1, with obvious spatial variation. In addition to the wind regime, the migration rate depended on dune morphology, density and vegetation cover; the rate was negatively related to dune height, density and vegetation cover, but positively linearly related to the length/width ratio (LU/W) and to the decrease in this ratio from 2003 to 2014. We found correlations among the dune morphometric parameters, but the relationships were weaker than in previous research. Due to the complexity of the factors that affect the processes that underlie sand dune development and migration, the morphological changes during dune migration were also complex. Our measurements suggest that the aeolian environment played a dominant role in dune migration and its spatial variation in the Quruq Desert. These results will support efforts to control dune migration in the western Quruq Desert and improve our understanding of dune morphodynamics. © 2019 John Wiley & Sons, Ltd.

Identifying the provenance of aeolian deposits in semi-arid zones of China is beneficial in understanding Earth’s surface processes and helping to alleviate ecological stress. In this paper, we use grain-size, geochemical elements, heavy-minerals, and quartz grain morphology data to investigate the potential source of aeolian sands from the Ordos Deserts (Mu Us Sandy Land and Hobq Desert). Sedimentological, geochemical and geomorphological results indicate that significant provenance differences exist among various parts of the Mu Us Sandy Land, i.e., aeolian sediments from the southwest region are obviously distinct from other areas in the Mu Us Sandy Land but show the same external provenance with the Hobq Desert referring to the sorting, mineralogical maturity, geochemical characteristics, heavy-minerals, and quartz grain morphology. Comparing the samples from the Ordos Deserts with felsic rocks from potential sources via a serious of geochemical methods, we conclude that: 1) Aeolian sands from other regions of the Mu Us are a mixture of binary provenance, i.e., one originated from local lacustrine sediments and underlying sandstones, and another from the Alxa Plateau (AP) carried by northwesterly Asian winter monsoon. 2) The fluvial deposits denuded from the Qilian Orogenic Belt in the Northeastern Tibetan Plateau (NTP) and carried by the Yellow River are likely the initial material source for the southwest region of the Mu Us Sandy Land and the Hobq Desert. 3) The Yellow River plays a significant and critical role in sediment transport for sand seas in arid and semi-arid areas of northern China.

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Exploring the impacts of anthropogenic factors on vegetation cover and future spatiotemporal trends in vegetation cover change are of great practical significance for sustainable management of the ecological environment. This study used the residual, trend analysis, Hurst index, and geographic detector methods to explore the spatiotemporal trends in the effects of anthropogenic factors on vegetation cover in Guanzhong, China from 2001 to 2018. The contributions of different kinds of anthropogenic factors to vegetation cover were quantitatively decomposed to identify those with the most effect. The main conclusions of the study included: 1) Although there was a positive trend in the effects of anthropogenic factors on vegetation cover from 2001 to 2018, this trend was projected to become negative in the future. This transition was evident in 45.53% of the total study area, mainly distributed in the cities of Baoji, Weinan, and Xianyang. The effects of artificial factors on reversing this deteriorating trend in the region should be noted. 2) The factors with the greatest influences on vegetation cover changes were popular tourist attractions, transportation, and urbanization rates. The influences of various factors on vegetation cover showed temporal variation, driven by societal and economic development, indicating the complexity and diversity of the influences of anthropogenic factors on vegetation cover. 3) Sustainable development should be promoted and the pressure on the ecology resulting from popular tourist attractions, the transportation network, and rapid urbanization should be reduced.