Wind erosion and dust emissions in central Asia: Spatiotemporal simulations in a typical dust year

Authors: PI, HUAWEI - Chinese Academy Of Agricultural Sciences; Sharratt, Brenton; LEI, JIANGQIANG - Chinese Academy Of Agricultural Sciences

Submitted to: Earth Surface Processes and Landforms
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/6/2018
Publication Date: 9/19/2018
Citation: Pi, H., Sharratt, B.S., Lei, J. 2018. Wind erosion and dust emissions in central Asia: Spatiotemporal simulations in a typical dust year. Earth Surface Processes and Landforms. 44(2):521-534. https://doi.org/10.1002/esp.4514.
DOI: https://doi.org/10.1002/esp.4514

Interpretive Summary: Dust emitted from landforms during high winds in central Asia affect air quality in the western United States. We estimated dust emissions from nine land use types in Xinjiang Province of western China, which is one of the most erosive areas in central Asia, using the USDA-ARS Wind Erosion Prediction System (WEPS). Dust emissions were nearly 10 times higher at Shisanjianfang in the Tu-ha Basin as compared to 63 other locations across the province due to desert land use and excessive occurrence of high winds. Deserts were at least four times more erodible than any other landform. Since the Taklimakan Desert constitutes 20% of Xinjiang Province, this desert significantly contributes to the atmospheric dust load that impacts downwind communities. Federal governing organizations are encouraged to promote the adoption of wind erosion control technologies in the Taklimakan Desert to improve air quality in eastern Asia and the western United States.

Technical Abstract: The prediction of dust emissions from landforms is important for identifying dust sources and for controlling dust emissions in arid and semiarid regions of the world. This study is concerned with the quantitative prediction of dust emissions in Xinjiang Province, central Asia. The Wind Erosion Prediction System (WEPS) was used to simulate annual soil and PM10 (particulate matter less than or equal to 10 µm in aerodynamic diameter) loss at 64 meteorological stations in the province. The model was validated using measurements of soil loss from three land use types (cotton, red date orchard, and desert) near Alaer in the Tarim Basin and suspension-size particle (dust) concentration at 18 meteorological stations throughout the province. Model validation suggested possible overestimation of soil and suspension-size particle loss by the WEPS, which may be due to the use of a common set of soil and crop parameters across all stations with the same land use in Xinjiang Province or a high threshold wind velocity. Simulated annual soil and PM10 loss were lowest in the Junggar and Tarim Basins (soil and PM10 loss were respectively 95.34 and 5.89 kg m-2 in the Junggar Basin and 113.81 and 9.27 kg m-2 in the Tarim Basin) and highest in the Tu-ha Basin (soil and PM10 loss were respectively 1520.18 and 87.13 kg m-2). Stations with the highest annual soil loss in the Tarim and Tu-ha Basins also had the highest number of days with wind speeds >8 m s-1. This indicated that wind is an important factor affecting soil loss in the region. The maximum monthly soil and PM10 loss occurred in April in the Junggar Basin, June in the Tarim Basin, and May in the Tu-ha Basin. This substantiates that dust storms occur most frequently during spring and early summer in the region.