Effect of soil order on the correlation between its properties and heavy metals in the Valle del Cauca, Colombia

The research was conducted using simple random sampling (SRS) in agricultural soils of the flat and piedmont areas of the Valle del Cauca. It demonstrates the effect of the soil orders Mollisols, Inceptisols, and Vertisols on the correlation of certain physical and chemical properties with heavy metals (HM). The Kaiser-Meyer-Olkin (KMO) index and Bartlett's test of sphericity were used to adjust the individual sampling of the indicators to a grouped form, performing Spearman correlation and principal component analysis (PCA). Vertisols had the highest number of associated indicators (pH, OM, EC, CICA, ɳ, CC, PMP, Ks, Da, Cd, Cr, Ni, and Co), followed by Mollisols (pH, OM, EC, CICA, ɳ, Ks, Da, Cd, Cr, Ni, Pb, and Co), and finally Inceptisols (pH, OM, EC, CICA, Ks, Da, Hg, Cr, Ni, and Co). Mollisols were associated with phenomena related to soil fertility and water movement. Inceptisols included soil conditions related to fertility, salt content, water velocity, and compaction. Fertility, moisture, water velocity, and compaction were linked to the Vertisols soil order, highlighting the importance of soil management in light of its heterogeneity in the region. In each soil order, the total concentration of Cr, Ni, and Co was associated with certain soil properties. Demonstrating that soil heterogeneity does not play an important role in the control or management of these elements.