Assessment of natural and anthropogenic factors on the distribution of chemical elements in soil from the Skopje region, Macedonia / Zagaduvanje Skopje

The main objective of this study is to present the distribution of different chemical elements in soil samples from the Skopje region, North Macedonia. To determine the level of presence of chemical elements, soil samples are collected from a total of 60 locations. From each location, from an area of 5
5 km2 samples of soil are collected: topsoil (0–5 cm) and subsoil (20–30 cm). The soil samples were analyzed for 69 elements by using two instrumental methods: inductively coupled plasma-atomic emission spectrometry (ICP-AES) for macro-elements and inductively coupled plasma-mass spectrometry (ICP-MS) for trace elements. A factor analysis was applied to analyze the factors affecting the linear combination variables grouped at the same factor. Spatial distribution maps of each factor as well as distribution maps for the analyzed elements were prepared by universal kriging interpolation. It was found that the distribution of most elements follows the lithology of the examined area, except for some elements (Cd, Cu, Fe, Hg, Mn, Pb, and Zn) whose higher contents are found in the area of the city of Skopje as a result of urban and industrial activities (traffic, metal processing, fossil fuel combustion for heating).