Assessment of heavy metal contamination of soils in the Republic of Tatarstan using complex pollution indices NPI, RI, BGI

Abstract

In this study, in most cases in soils susceptible to the accumulation of heavy metals, the highest content of heavy metals was observed in the surface layers of the soil profile. We calculated the values of three pollution indices based on the determination of individual heavy metals (Al, As, Cd, Pb, Sr) and pollutants (Cu, Co, Cr, Zn, Mn, Fe, Mo, Ni) in the territory of the Republic of Tatarstan. The overall degree of pollution and environmental risk assessment were carried out using complex indices NPI and RI. The possibility of accumulation of individual elements in soil horizons was determined using the iogeochemical index BGI. The content of heavy metals in the soils of the Republic of Tatarstan, such as As, Pb, Co, Cu, Fe in the soil horizons was several times higher than the natural content of these metals, which is confirmed by three calculated indicators, taking into account that the values obtained for the O horizon using NPI indices and RI are consistent with each other, and BGI is consistent for individual elements (As, Pb, Co, Cu, Fe, Cd, Cr, Mn and Mo).