Dune Slowdown and Stabilization in Inland Deserts of East Asia: The Role of Wind Stilling and Vegetation Recovery over Four Decades

Aeolian processes on planetary surfaces are governed by atmospheric dynamics and surface properties, yielding similar landforms across a wide range of environments. On Earth, recent climate change, particularly the decline in near-surface wind speeds (terrestrial stilling) and variations in other climatic factors, has significantly influenced aeolian landscapes. In the inland deserts of Central and East Asia, these changes have led to reduced dune migration, dune stabilization and transformation, fewer dust storms, and increased vegetation recovery in the drylands.

This study investigates the coupled effects of wind speed reduction and vegetation restoration on the mobility and stability of sand dunes in northern China, located at the junction of the Gobi, Badain Jaran, and Tengger deserts. Vegetation changes were assessed using multiple NDVI time series, which revealed a general increase in vegetation across the study area, despite notable spatial heterogeneity. This greening trend is primarily driven by wetter, warmer, and less windy climatic conditions during the past few decades, further amplified by large-scale ecological restoration programs. While vegetation expansion has not fully stabilized the dunes in most areas, it has contributed to reduced migration rates and altered dune morphology.

In extreme arid zones with negligible vegetation growth over the past decades, dune migration rates were analyzed using Landsat satellite imagery (1986–2021) and the COSI-Corr procedure, constructing a 35-year time series across multiple sites. The results demonstrate a consistent decline in dune migration rates, aligning with the trend of terrestrial stilling. This suggests that recent adjustments in atmospheric circulation under global climate change have significantly slowed dune migration. Model calculations further reveal reduced sand flux under declining wind speeds, consistent with the cubic relationship between wind speed and sand transport, validating theoretical sand transport laws at larger spatial scales.

These findings underscore the critical role of atmospheric circulation in shaping aeolian landforms and emphasize the combined effects of climate change and human activities in stabilizing sand dunes. By integrating these terrestrial insights into planetary aeolian research, this study offers valuable analogues for understanding dune dynamics under varying atmospheric conditions across planetary surfaces.