Although urban and suburban soils are used for many purposes, some of them relevant to agricultural and forest sciences, that these intensively managed and disturbed soils have not been extensively investigated up to now is suggested by the white areas representing most urban zones on soil survey maps, Because urban soils are often developed on composite materials derived from previous uses and exogenous sources, spatial heterogeneity is a typical feature. Their evolution is controlled almost exclusively by humans, who impose very rapid transformation cycles compared with those occurring in less disturbed areas. However, there is a continuum from the natural soils to the extensively disturbed soils, and their basic functions are essentially the same. As a result of their origin and uses, urban soils may contain pollutants, the location, characteristics, and potential evolution of which must be established clearly to ensure safe land uses. These soils can be investigated with the traditional soil survey approach when the techniques are adapted properly to the urban context. A multidisciplinary approach is necessary to ensure that urban soils are well understood in order to ensure their optimum use.
