Abstract
Soil quality is related to soil characteristics such as fertility and contamination. The aim of this study is to assessthe effect of land use on these soil characteristics and to confirmthe following anthropisation gradient: (i) forest,(ii) grassland, (iii) cultivated, (iv) orchard and vineyard, (v) urban vegetable garden, and (vi) SUITMA(urban, industrial,traffic, mining and military areas). A database comprising the characteristics of 2451 soils has been constituted.In order to compare the topsoils from six contrasting land uses, a principal components analysis (PCA)was performed on nine geochemical variables (C, N, pH, POlsen, total Cd, Cu, Ni, Pb, Zn). The first axis of the PCA isinterpreted as a global increase of topsoil metallic elements along the anthropisation gradient. Axis 2 reflects thevariability of fertility levels. Human activity increases the pressure on soils along the proposed gradient accordingto six different distribution patterns. This better knowledge of topsoil quality and its dependence on current landuse should therefore help to manage and preserve the soil mantle.