磁化率特征揭示出的昆玉高速公路跑马山段土壤重金属污染状况

Status of Heavy Metal Contamination by Roadside Topsoil Revealed by the Characteristic of Magnetic Susceptibility in Kunming-Yuxi Freeway

利用环境磁学的手段对昆玉高速公路跑马山段左右两侧表层土壤进行监测,发现高速公路两侧表土磁化率(lχf)有向公路增加的趋势,其中距离公路20m以内的地带这种趋势最为明显。频率磁化率(fχd%)分析表明,磁化率值向高速公路增大趋势与成壤作用形成的超顺磁颗粒(SP)无关,预示着土壤受到了污染,而距离公路20m的地带污染最为明显。

The magnetic susceptibility and frequency- dependent susceptibility of roadside tipsoil from Paomashan section of Kunming - Yuxi Freeway were studied to monitor environmental pollution. The results showed that magnetic susceptibility （Xlf） increase as the distance from the road decreasing, and the trend is most obvious within 20 meters away from the road. Frequency -dependent susceptibility （Xdf） analysis indicated that the above trend has no relationship with superparamagnetic particulates （SP） formed in the soil forming processes, which indicated that topsoil had been contaminated, and the region within 20 meters away fi＇om the road has been polluted mostly.