Determination of heavy metals (cadmium and lead) concentrations, pH, and electrical conductivity in agricultural soils of Khatam city and zoning using the GIS softwareDetermination of heavy metals (cadmium and lead) concentrations, pH, and electrical conductivity in agricultural soils of Khatam city

Introduction: Improper use of chemical fertilizers, in particular phosphate fertilizers, increases soil concentrations of heavy metals such as lead and cadmium. Due to the environmental hazards of these metals, it is essential to continuously monitor the concentrations of these metals in soil. The aim of this study was to determine cadmium and lead concentrations, pH, and electrical conductivity (EC) in agricultural soils of Khatam city and zoning using the GIS software. Materials and Methods: The present descriptive-analytical study was carried out in Khatam city during 2018. Metal concentrations, pH, and EC were measured using an atomic absorption device, a pH meter (model MI150), and a Lutron conductivity meter (model CD -4306), respectively. Descriptive statistical analysis and zoning were done using SPSS software version 16 and ArcGIS software. Findings: Mean concentrations of lead and cadmium in soil were determined as 14.83 ppb and 0.175 ppb, respectively (Table 1). Based on the measurements, pH values in soil samples were in acidic to slightly alkaline range (5-8.3). Similar to pH values, EC ranged from 0.71 to 1.12 µSiemens. Conclusion: According to the results, the measured lead and cadmium concentrations in Khatam city are much lower than the standard provided by the World Health Organization (WHO), which poses no health problems in terms of crop consumption by the consumers in this region.