Evaporite‐Derived Salts in Dust Generated by Saltation‐Sandblasting From the Qaidam Basin: Implications for Dust Aging and Atmospheric Chemistry

Abstract Freshly emitted mineral dust is typically dominated by silicates, but evaporite‐rich sources can release substantial soluble salts. However, the abundance, size distribution, and mixing state of primary salts in nascent dust remain poorly constrained. Here, we investigated individual dust particles generated by saltation‐sandblasting processes from surface soils of the evaporite‐rich Qaidam Basin (QB) on the northern Tibetan Plateau. Our results reveal pronounced spatial heterogeneity in particle composition across the basin. Salt‐containing minerals were abundant in the northwestern basin (59.5%), less common in the eastern and southwestern regions (11.1%–18.4%), and rare in the central basin (3.1%). These minerals were dominated by sulfate‐ and chloride‐containing species and occurred predominantly as components internally mixed with silicate particles, rather than as discrete crystalline phases. Particles from the northwestern QB exhibited S/Al mass ratios of ∼1.1–2.2, frequently larger than those reported for highly aged Asian dust. Compared with dust from other deserts, QB dust is characterized by finer particle sizes, substantially higher salt contents, and widespread salt–silicate internal mixing. These findings indicate that the QB represents an evaporite‐influenced dust endmember rather than a variant of conventional silicate‐dominated dust sources. Given the widespread occurrence of evaporite‐rich arid regions, mineral sulfate and chloride should be explicitly incorporated into assessments of the role of dust in atmospheric chemistry and climate.