Determination of heavy metal levels using Betula pendula Roth. under various soil contamination in Southern Urals, Russia

Abstract

Heavy metals are hazardous to environmental and human health. Metals contained in the solid fraction of emissions are fixed in the soil absorbing complex and tend to bioaccumulate in plants, which can be used both to diagnose the level of contamination of forest biogeocenoses and to study the laws of the processes of absorption of contaminants in the soil–plant system. The research aims to determine the degree of pollution in Betula pendula Roth. from emissions from Combine Magnesite (magnesite ore processing and mining plant activity area in Russia) at 1, 3, 10, and 100 km far from the emission source, which experimental plots created in the 1980s. Soil samples were collected from these sites, and 1- and 2-year-old branches and leaf specimens were collected from B. pendula individuals. The lead (Pb), chromium (Cr), and iron (Fe) concentrations in soil and organs of B. pendula by the soil depth, washing, organ type, and organ age were determined. As a result, the variations in element concentrations by organs at all the distances and distances for all the organs were significant (p < 0.05). Metal concentrations were higher in the subsoil and leaf collected from 2-year-old branches. These results were interpreted as the higher values in the leaves of 2-year-old branches exposed to heavy metals in the air for a longer time, and the heavy metal concentrations in the subsoil increased due to the decomposition of these leaves. The movement of heavy metals, such as Pb and Cr, in soil was minimal.