Magnetic characteristics of atmospheric dustfall in a subtropical monsoon climate zone of China and its environmental implications: A case study of Nanjing
Magnetic characteristics of atmospheric dustfall in a subtropical monsoon climate zone of China and its environmental implications: A case study of Nanjing
复制标题
中国亚热带季风气候区大气降尘磁特征及其环境意义——以南京市为例
DOI：
10.1016/j.atmosenv.2019.05.039
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发表时间：
2019-09-01
影响因子：
5
通讯作者：
Liv, Xianbin
中科院分区：
文献类型：
--
作者：
Wang, Longsheng;Hu, Shouyun;Liv, Xianbin
南京地处中国亚热带季风气候区。本研究于2015年2月至2016年3月对南京某高层建筑的不同方向进行了一系列月度大气降尘数据采集。从大气降尘样品中测量了一系列磁参数，包括chi、chi(fd)%、chi(ARM)、SIRM、磁滞回线、高温kappa-T曲线和SEM图像。研究表明，南京大气降尘样品中磁性矿物的种类和大小与我国北方城市相似，但南京大气降尘样品中磁性矿物浓度较高。磁性矿物以粗粒磁铁矿为主。南京大气降尘中磁性矿物的峰值浓度出现在夏季。磁参数与气象数据的关系表明，高值主要受降水影响，而非风向。结合SEM图像结果以及磁参数与PM 2.5、PM10数据的弱相关性，表明南京大气降尘主要来自近源污染降尘，而非远距离降尘。这项研究表明，环境磁学作为一种简单、经济和无损的技术，将成为大气降尘研究的有用工具。
Nanjing is located in the subtropical monsoon climate zone of China. In this study, a series of monthly collections of atmospheric dustfall was performed in different directions from a high-rise building in Nanjing from February 2015 to March 2016. A series of magnetic parameters including chi, chi(fd)%, chi(ARM), SIRM, magnetic hysteresis loops, high-temperature kappa-T curves and SEM images was measured from atmospheric dustfall samples. The research shows that the type and size of magnetic minerals within atmospheric dustfall samples in Nanjing are similar to those found in northern cities in China, but the atmospheric dustfall samples in Nanjing have higher magnetic mineral concentrations. Coarse-grained magnetite dominated magnetic minerals. The peak concentrations of magnetic minerals contained from atmospheric dustfall of Nanjing occurred in summer. The relationship between magnetic parameters and meteorological data shows that the high values are mainly influenced by precipitation rather than by wind direction. Combined with results of the SEM images and the weak relationship between magnetic parameters and the data of PM 2.5 and PM10, all these indicate that the atmospheric dustfall of Nanjing is mainly from near-source polluted dustfall rather than from long-distance dustfall. This research suggests that environmental magnetism as a simple, economic and nondestructive technology, will be a useful tool in atmospheric dustfall research.