In terms of the formation of dust sources in northern China, one is naturally formed Quaternary deposits and accumulations; the other is accumulations of human production activities. The former includes eolian sand, gravel gobi, wind eroded bad land, sandy clay, Tertiary red sandstone, modern fluvial alluvium, lacustrine deposit, loess, etc. These dust sources have a large mass and wide distribution area, which provide a rich material basis for the formation of strong dust storms. The latter includes tailings, wastes, ashes and other deposits, as well as the bare ground of cultivated land, such as degraded forest grassland, dry pine land without vegetation cover and sand piles of urban and rural construction sites. In recent years, sandy grassland and dry cultivated land are the main sources of sand. In terms of natural causes, human beings cannot eliminate sandstorms. However, from the perspective of human activities, the negative effects of deforestation and unreasonable use of land and water resources to accelerate the occurrence of sandstorm can be reduced, and the frequency and intensity of sandstorm can be reduced to a certain extent.
沙源物质颗粒的大小也影响沙尘飞行的距离。如科尔沁沙地组成物质主要是中细砂粉砂层和粉细砂。鄂尔多斯等地含细砂、粉砂高达80%。松散沉积环境加上合适的环流条件,使这些地区成为沙尘暴的高发区和物源区。沙尘发生地区辽阔坦荡的地貌也是成因之一。
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