Evaluation of trace elements MPC in agricultural soil using organic matter and clay content

The aim of this paper is to investigate the contribution of the influence of organic matter and clay content on the value of maximum permissible concentrations (MPC) of trace elements Pb, Ni, Cr, and Cd. The investigation was conducted on agricul­tural soil in the territory of Veliko Gradište Municipality. There were analyzed 82 samples of eutric cambisol type soil, 17 samples of chernozem soil, and 32 samples of sandy soil. In the composite soil samples, taken from a depth of 0-30 cm, main parameters of soil fertility (pH, P2O5, K2O, CaCO3, soil organic matter - SOM), the content of the clay frac­tion, and total forms of Pb, Ni, Cr, and Cd were determined. Interpretation of the obtained results was carried out in relation to the MPC of trace elements defined in the Regulations (Official Gazette, 88/2018). Based on the ratio of the defined MPC and corrected values whose calculation includes the values of the organic matter and clay content, there was determined the correlation concerning the content of organic matter and the content of clay fractions, respectively, in the tested samples. In addition, the content of Cr and Pb in tested types of soil still did not exceed the adjusted MPC value. As for Cd and Ni, there was no deviation from the established and modified values of MPC. Concludingly, the research should be continued and supplemented by data for other types of soils, which would represent a base for a further assessment of the applicability of the existing regulations taken from Dutch sources and incorporated into Serbian Regulations (Official Gazette, 88/2018). [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR-37006]