Deciphering dust provenance and transport pathways across Northern China's source-sink systems

Abstract. Northern China's arid lands constitute one of Earth's most active aeolian ecosystems, yet persistent uncertainties remain regarding the precise source apportionment of dust emissions impacting downstream regions. By applying advanced geochemical fingerprinting techniques to modern airborne dust samples collected from 11 to 29 April 2023 across major potential provenance areas (Taklimakan, Gurbantunggut, Hexi Corridor, Heihe River Basin, Alxa Plateau, and Qaidam Basin Desert), we systematically quantified dust provenance through coupled rare earth element signatures and trace element ratios. Our multivariate analysis reveals three critical findings: (1) The Taklimakan and Gurbantunggut deserts dominate as primary provenance than Alxa Plateau, Hexi Corridor and Heihe Basin and the Qaidam Basin Desert; (2) Despite the Taklimakan and Gurbantunggut Desert's upwind position relative to the CLP, the intervening Alxa Plateau (> 1500 ma.s.l.) acts as a topographic filter of dust destined for the Lanzhou and Mu Us regions while facilitating multi-phase recycling through localized deposition and remobilization; (3) Provenance shifts exhibit strong spatial dependency, with Lanzhou's dust load dominated by Gurbantunggut provenance (26.1 %), then Taklimakan (18.3 %); but Mu Us dust dominated by Alxa (27.5 %), then Taklimakan (21.6 %). These findings redefine our understanding of East Asian dust dynamics by demonstrating how elevation barriers and sedimentary recycling jointly modulate source-sink relationships over millennial scales.