Differences in Dust Emission and Near‐Surface Transport Patterns Among Three Surface Substrate Types

Abstract

ABSTRACT Soil wind erosion is a major driver of atmospheric dust emissions and land degradation. Many studies have examined dust release from different substrates, but differences in methods and units still limit quantitative understanding of how surface conditions and wind jointly control dust emission and near‐surface transport. A closed‐circuit wind tunnel was used to compare dust emission and vertical transport from dune sand (sand, D 50 = 176 μm), farmland soil (sandy loam, D 50 = 86 μm), and dry lakebed sediments (sand, D 50 = 153 μm). At 14 m s −1 , farmlands transported 6.2–7.2 times more PM 2.5 and 7.1–8.3 times more PM 10 than the other two substrates ( p < 0.001), while dunes and lakebeds transported more total mass. In the emitted material, dunes contributed the lowest fine particle proportion (PM 63 < 6.6%), farmlands maintained high fine fractions (PM 63 up to 55.5%), and lakebeds produced fine‐rich emissions at low wind speed but shifted towards low fine fractions as speed increased. Vertically, fine‐particle proportions increased with height over farmland soil across all wind speeds. Under the strongest wind, dune sand and dry lakebed sediment showed declining transported‐mass profiles and no significant height trends in particle‐size proportions. These results show that the surfaces that dominate total mass are not the same as those that dominate health‐relevant PM. This unified comparative analysis, grounded in controlled wind‐tunnel observations, supports targeted mitigation through modest‐height windbreaks for fine‐dust control on farmland, surface‐roughness enhancement on dunes, and crust stabilization on dry lakebeds.