Causes of Soil Contamination in the Urban Environment

Abstract

This chapter gives information about all kinds of contaminant sources of soils in urban environments. The description is mainly focused on heavy metals but also a number of organic pollutants, e.g. petroleum hydrocarbons, PAH and PCB, are of concern. Urban-to-rural gradients, depth gradients and relations to urban and industrial land uses are discussed in association with dust deposition. Different typical urban land uses such as parks and gardens in a number of examples worldwide are introduced. Special attention is paid to linear soil contamination with metals, petroleum hydrocarbons and de-icing salts along roadsides. Furthermore, soil contamination of floodplains in longitudinal and vertical direction located in urbanized areas is presented. Due to fertilizing with problematical mineral compounds and application of sewage sludge, wastewater and pesticides, particularly soils used for horticultural purposes in the urban environment potentially receive contaminants which are also integrated in the presentation of possible soil contamination sources. However, the chapter deals predominantly with soil contamination in relation to urban influences. Accordingly, reasons and extent of contamination of derelict land (industrial plots used in former times), anthropogenic deposits such as heaps and dumps as well as accident sites are taken into account. Many examples in different countries are given in order to illustrate the situation in detail. Finally, the chapter will provide a helpful tool to identify and separate the distinct contamination patterns described.