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对长武和宜川晚第四纪黄土-古土壤序列的高分辨率铁含量分析表明，不同时期的风尘在化学成分上具有较明显的区别。在排除成壤过程中CaCO3淋溶和淀积的相对影响后，研究剖面的铁含量基本反映了原始风尘的铁含量。已有研究表明，西部源区的气溶胶和现代地表流沙中铁的相对含量显著高于东部源区。本文认为，风尘铁含量的变化反映了西部沙漠风尘对黄土堆积的相对贡献。由于西风带北支是西部源区风尘的主要搬运者，风尘中全铁含量可能反映了西风带北支气流的强度，并明显存在着千年尺度的变化。
The analysis of the high resolution iron content of the late Quaternary Loess-Paleozoic sequence in Changwu and Yichuan shows that there are obvious differences in the chemical composition between dust and dust in different periods. After excluding the relative influence of CaCO3 leaching and deposition during pedogenesis, the iron content of the study profile basically reflects the iron content of the original dust. Studies have shown that the relative content of iron in western source areas and modern surface sediment is significantly higher than that in eastern source areas. This paper argues that the change of dust content in iron dust reflects the relative contribution of dust dust in the western desert to the accumulation of loess. Since the north branch of the westerly belt is the main carrier of dust in the western source area, the total iron content in dust and dust may reflect the intensity of the north branch airflow in the westerly zone and obviously there is a change in the millennium scale.