西南特殊地形区域大气降尘中矿物颗粒特征

Characteristics of mineral particles in atmospheric dust fall in special terrain of southwest China

为研究西南特殊地形区域大气降尘中矿物颗粒特征,于2021年9-10月在川西的康定市和马尔康市以及川南的攀枝花市采集了大气降尘样品,分析了大气降尘样品的化学组分和矿物相,并研究了区域气团迁移和降尘矿物颗粒来源,结果表明:川西降尘中有鲕粒状矿物,攀枝花降尘中大多为球状矿物,矿物相有方解石、石英和白云母等,攀枝花降尘中还有较高质量分数的赤铁矿;康定和马尔康降尘主要受生物质燃烧源和矿尘影响,城市气团主要受来自四川盆地的雅安气团影响,还受少量来自青藏高原和西北沙漠区气团影响,而攀枝花降尘主要受燃煤排放和移动排放源影响,城市气团主要受来自云南的气团影响。研究成果可为西南特殊地形区域精准控制大气污染提供技术支撑。

To study the characteristics of mineral particles contained in atmospheric dust fall in the special terrain of southwest China,dust fall mineral particles were collected from Kangding and Barkam(in western Sichuan)and Panzhihua(in southern Sichuan)from September to October 2021,and the chemical composition and mineralogy of atmospheric dust fall was analyzed,the migration of the air-mass and the source of the dust fall mineral particles were studied.The results show that the dust fall in western Sichuan was composed of oolitic minerals,while those coming from Panzhihua contained spherical minerals.Minerals in dust fall included calcite,quartz and muscovite and also hematite with high concentration from Panzhihua.The dust fall in Kangding and Barkam was mainly subjected to biomass combustion sources and mineral dusts,and the urban air-mass was mainly coming from Ya'an in the Sichuan Basin and also subjected to a small amount of air-mass from the Qinghai-Tibet Plateau and the Northwest desert.The dust fall in Panzhihua was mainly coming from coal combustion discharge and mobile discharge sources and the urban dust fall was subjected to air masses from Yunnan.The results of this study can be provided as a support for the precise control of air pollution in the special terrain of southwest China.