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Recent studies have shown that the dust emission efficiency (Ed) of some soil surfaces undergoes changes with wind speed and that such changes are related to soil properties. Through wind tunnel experiments, we investigate the comprehensive effect of soil particle size composition (PSC) (both minimally and fully dispersed) and friction wind speed (u*) on Ed. Results show that Ed initially increases and then decreases as soil texture changes from fine to coarse, with intermediate‐textured soils having the highest Ed and the strongest dust emission ability. The ratio of silt to sand in soil is an index suitable for reflecting the influence of soil texture on Ed. The PSC of soil dry aggregate is a factor that directly determines Ed. With increasing u*, Ed tends to increase for coarse‐ and intermediate‐textured soils but not for fine‐textured soil, supporting the view that Ed is influenced by u* and that the influence is related to soil PSC. Despite the fitting power function equations between Ed and u* for some soils failing to pass the significance test in this study, the substantial influence of soil texture on the power exponents implies potential for establishing an equation capable of expressing the comprehensive effect of soil texture and u* on Ed. Plain Language Summary: The mineral dust emitted from soil wind erosion not only pollutes the atmospheric environment and harms human health, but also plays an important role in the atmospheric physical and chemical processes and the global ecosystem. Improving the prediction accuracy of dust emission models is the basis for scientific research on the effects of dust on the ecological environment. Dust emission efficiency is an important input parameter of dust emission models, and its accurate expression is the key to improve the prediction accuracy of dust emission models. Hence, in the report we study the comprehensive effect of soil particle size composition and wind speed on dust emission efficiency. We find that the dust emission efficiency is influenced by friction wind speed for coarse‐textured and intermediate‐textured soils. The dust emission efficiency initially increases and then decreases as soil texture changes from fine to coarse. There is significant effect of soil texture on the relationship between dust emission efficiency and wind speed. The study confirms the probability for establishing an equation of expressing the comprehensive effect of soil texture and wind speed on dust emission efficiency. Key Points: Wind speed influence dust emission efficiency, especially for coarse‐textured and intermediate‐textured soilsDust emission efficiency initially increase and then decrease as soil texture changes from fine to coarseThere is a comprehensive effect of wind speed and soil texture on dust emission efficiency [ABSTRACT FROM AUTHOR]

The question of whether the emitted dust size distribution (EDSD) depends on wind velocity or soil size distribution (SSD) remains to be resolved. This study used wind tunnel tests to investigate the influence of wind velocity and SSD on EDSD. The results showed that EDSD was influenced by both wind velocity and soil texture, supporting the saltation bombardment theory. The ratios of PM2.5 to PM10 (RPM2.5/10) and PM1.0 to PM10 (RPM1.0/10), which reflect the EDSD in the range of 0–10 μm, both showed trends of increase with increasing friction velocity (u*) for all six tested soils. The trend of increase was more significant for RPM1.0/10 than for RPM2.5/10, which indicates that the content of finer dust in the range 0–10 μm increased with increasing u*. When u* increased from 0.51 to 0.68 m s−1, the ranges of increase for RPM2.5/10 and RPM1.0/10 were most significant for sandy soils, followed by sandy loam soils and then loamy soils, indicating that the effect of wind velocity on EDSD increased with increasing sand content in the soils. The EDSD was also influenced significantly by the fully dispersed SSD, especially the sand and silt contents in the soils. The RPM2.5/10 and RPM1.0/10 increased (decreased) logarithmically (linearly) with increasing sand (silt) content in these soils. The finding of this study represents enrichment of data regarding EDSD, which could lead to greater understanding of the roles of wind velocity and SSD in relation to EDSD. Key Points: Wind velocity affects emitted dust size distribution, especially for sandy soilsEmitted dust size distribution is influenced greatly by fully dispersed soil size distribution, especially the sand/silt contents in soilsContent of finer dust in the range 0–10 μm increases with increasing wind velocity and coarsening soil texture at the time of emission [ABSTRACT FROM AUTHOR]

Dust emission depends directly and indirectly on soil particle distribution, but little information is available that examines dust emission potential and its relationship with wind erosion for different soils. This study aimed to elucidate the difference in wind erosion characteristics between loamy farmland (LF) and sandy farmland (SF) and discuss the influence of this difference on dust emission potential. Field observations were conducted during 2012–2016 in Bashang district, North China. With increasing friction wind speed, the horizontal mass flux increased exponentially in LF but obeyed the power function in SF. The horizontal mass flux was higher in SF than in LF, but the gap narrowed from 766 times at friction wind speed of 0.3 m s−1 to 50 times at 0.6 m s−1. The dry aggregate size distribution of sediment in LF was finer than in SF. Fine particle content (diameter < 0.05 mm) in windblown sediment was much higher in LF (31.39%) than in SF (5.92%), which was influenced by parent soils. With height increasing, the mass percentage of sediment decreased more rapidly in SF than in LF, with 86% and 66% of sediment clustering at height 0–20 cm, respectively. Because the horizontal mass flux and dust content in sediment both increased more quickly in LF than in SF with increasing friction wind speed, the dust emission potential was larger in LF than in SF under strong winds. The adverse effect of dust emission in loamy soils on atmospheric pollution should receive more attention in strong wind erosion events. [ABSTRACT FROM AUTHOR]