High‐Altitude Aeolian Research on the Tibetan Plateau

Abstract

Aeolian processes and their role in desertification have been studied extensively at low elevations but have been rarely studied at high elevations in areas such as the Tibetan Plateau, where aeolian processes were active in the geologic past and remain active today. In this review, we summarize research that improves our understanding of aeolian processes on the Tibetan Plateau, including the distribution, characteristics, and provenance of aeolian sediments; the history of aeolian activity; aeolian geomorphology; and wind‐driven land degradation. Contemporary aeolian processes primarily occur in dry basins, in wide river valleys, on lakeshores, on mountain slopes, and on gravel pavements. Sediment characteristics suggest a local origin and provide interesting contrasts with those of China's Loess Plateau. The history of aeolian activity and its paleoclimatic implications, reconstructed based on aeolian archives, is short (mostly since the Late Glacial) and shows wide regional differences. Aeolian geomorphology is simple and suggests short formation time. Wind‐driven land degradation is less severe than previously thought, driven by different factors in different areas, and exhibited complex interactions with freeze‐thaw processes. Aeolian research has been conducted within the general framework of aeolian science but addresses issues specific to the Tibetan Plateau that arise due to the low air temperature, low air density, and the presence of a cryosphere. We propose six priorities for future research: aeolian physics, the effect of freeze‐thaw cycles, comparisons with other areas, regional differences, effects of wind‐driven land degradation, and integrated observation and monitoring.

Influence of salinity and moisture on the threshold shear velocity of saline sand in the Qarhan Desert, Qaidam Basin of China: A wind tunnel experiment

“…Disturbance or destruction of the salt crust can reduce the wind speed threshold of dust emission and increase the release of dust (Nield et al, 2016). In Qaidam Basin, saline sediment influences dune evolution and alters sand dune morphology (Rubin and Hesp, 2009;Wolfe and Hugenholtz, 2009;Rubin and Rubin, 2013;Dong et al, 2017;Xiao et al, 2017;Zhang et al, 2018). Although, there has been much research on the sediment and dune composition, wind conditions, dune patterns and the temporal aspects of dune formation (Rubin and Hesp, 2009;Zhou et al, 2012;Li et al, 2015Li et al, , 2016Zhang et al, 2018).…”

Mega‐blowouts in Qinghai–Tibet Plateau: Morphology, distribution and initiation

“…The region has a cold arid to semi‐arid continental climate with an average precipitation of 250 ~400 mm, mean annual temperature ranging from −0.37 ~3.7°C and potential evaporation of 1717 mm (Li et al, ). Strong north and northwest winds prevail in spring and winter with a maximum wind speed in spring up to 40 m/s (Dong et al, ; Li et al, ; Dong et al, ). The region has an average altitude of ~3000 m, glaciers and discontinuous permafrost exists on mountains (Luo et al, ; Ran et al, ).…”

“…The region has an average altitude of ~3000 m, glaciers and discontinuous permafrost exists on mountains (Luo et al, ; Ran et al, ). The global significance of the region for understanding continental geodynamics is widely recognized due to the rich geologic records exposed in the mountain and river systems (Qiang et al, ; Dong et al, ).…”

“…As they develop, blowouts have a positive feedback which causes further reduction of vegetation (land degradation). They may also cause the release of dust into the atmosphere which has a detrimental effect on air quality (Dong et al, ). Based on ensemble models, the Intergovernmental Panel on Climate Change (IPCC) (Stocker et al, ) predicts that most arid and semi‐arid areas on Earth will become drier over the next century.…”

Characteristics of Desertification and Short-Term Effectiveness of Differing Treatments on Shifting Sand Dune Stabilization in an Alpine Rangeland

“…Rangeland desertification in these regions commences with the degradation of grassland or marshland, and continues towards an extremely serious state (e.g., mobile sand dunes), considered the final stage of land degradation [4,5]. Climate warming, decreasing precipitation, overgrazing, rodent damage, and repeated freezing-thawing actions are thought to be the primary driving factors responsible for the expansion of rangeland desertification on the eastern QTP [6][7][8][9][10].…”