Factors controlling spatio-temporal variations of sandy deserts during the past 110 Years in Xinjiang, Northwestern China

Abstract

Xinjiang, northwestern China, has the largest area of sandy desert landscapes in the northern hemisphere mid-latitudes and is known to be subject to so-called sandy desertification. Longer-term records of changes in the distribution of sandy desert landscapes are required to develop a more comprehensive understanding of mechanisms underlying their spatial and temporal dynamics. Here, we integrate a diverse range of data sources, including historical maps, documentary accounts, government statistics, remote sensing data, global climate reanalysis data, and field reconnaissance data, to reconstruct 110 years of spatial variations in sandy desert distribution in Xinjiang. Our results show that, overall, there has been a 22.3% reduction in the area of sandy desert in Xinjiang over the past 110 years. Cross-wavelet and linear regression analyses reveal that vegetation changes are the major determinants of sandy desertification during this period and that, in contrast to previous studies in the region, aeolian factors and human-induced degradation are less important drivers than previously reported. Ecosystem management has markedly constrained sandy desert expansion even against a background of population increase. The suggested comprehensive approach may be useful in improving understanding of sandy desert dynamics and associated desertification forcing mechanisms in arid and semiarid regions globally.