环境磁学在监测城市河流沉积物污染中的应用

环境磁学因简便、快速、经济等特征而逐渐广泛应用于城市环境污染研究,并得到了大量学者的认可.与此同时,对环境磁学污染响应机理的研究也成为当前环境磁学发展突破点.本文选取流经兰州市不同功能区（绿地区、生活区、商业区、工业区）的典型河流——寺儿沟为研究对象,通过环境磁学、元素、粒度等指标对其4个功能区河段沉积物的磁性特征进行...

Use of environmental magnetism to monitor pollution in the river sediment of an urban area

Abstract: With the advantage of fast, sensitive, inexpensive, nondestructive measurement, magnetic method has been used as a preliminary method for studying pollution effects before starting time consuming and expensive chemical methods. In this study, a representative river, Sier River, was selected for particle size, elements and magnetic property measurement with the purpose of exploring the sediment magnetism response to different functional areas. The results indicate that river sediments collected in Green district and residential areas are characterised by low concentration of magnetic minerals and a small amount of maghaemite, while that collected in commercial district and industrial areas are characterised by high magnetic mineral and little maghaemite. Origin of maghaemite can be used to indicate the river pollution, but mineral grain sizes are not an effective indicator in urban area. The comparison of the sediment magnetic properties with the degree of pollution reveal that although the degree of pollution is the highest in commercial district, the highest magnetic susceptibility was measured in sediments from the Industrial area, which implies that although the magnetic susceptibility increased significantly when the degree of element enrichment was high, the increase is nonlinear in different types of sediments. The study indicates that various magnetic parameters should be used and the influence of source should be minimized when monitoring the pollution using environmental magnetism method.