Heavy Metals and Physico-Chemical Properties Inter-Relations in Agricultural Soils, Tanjaro Sub-District, Iraq

Abstract

In the current study, agricultural soil samples were collected from 30 different locations in Tanjaro sub-district, north of Iraq. Soil samples were analyzed for identifying the concentration of 16 heavy metals and 9 soil property parameters using inductively coupled plasma optical emission spectroscopy (ICP-OES) and other analyzing tools. Multivariate and geospatial statistics have been applied to investigate links between heavy metals and soil properties. Descriptive statistics showed considerable variation exists in concentrations of the investigated parameters among sampling locations. Multiple correspondence analysis (MCA) revealed that the highest relationships were for soil organic matter (SOM), particularly with Cd, Co, and Hg. Agglomerative hierarchical clustering (AHC) and factorial analysis (FA) classified soil property relationships with heavy metals into three distinctive categories of heavy metals: naturally existed; originated from anthropogenic sources; and with no significant relationships. Plotting spatial variation of investigated soil parameters using Kriging interpolation for extracted factor from FA showed that soil properties in northern parts of the study area are more impacted by heavy metals came from anthropogenic activities. This study gives further insight into relationship patterns of soil properties with heavy metals, leading to improve the sustainability of agricultural land.