Quantifying the contribution of dust sources in the arid area of northwest China using multivariate statistical techniques and Bayesian mixing models

摘要

In this study, topsoil samples and dust samples during dust storms were collected from the main dust source in northwest China, the geochemical elements were measured, and the contribution of dust sources was quantified using a discriminant function analysis (DFA) model and a MixSIAR model. Finally, the accuracy of the model was evaluated using an artificial mixture sample. The results showed that the dust sources and their contributions were significantly heterogeneous due to the natural and anthropogenic influences on the source-transport-sink process. DFA and MixSIAR models showed that the main dust sources in Dunhuang and Jiuquan were the Western Gobi and Western oasis, and Zhangye was mainly influenced by the Western Gobi, Western oasis, Middle Gobi, and Central oasis, with the influence of the Middle oasis being more pronounced. The Eastern Gobi, Eastern oasis, Badain Jaran desert, and Tengger desert have a greater influence on Jinchang, Wuwei, Baiyin, and Lanzhou. The contribution of each dust source in the Hexi region was found to show a significant distance effect. The accuracy of the models varied depending on the number of dust sources. The study provides new ideas for quantifying the contribution of dust source and for global dust storm control.