SPATIAL DISTRIBUTION OF CHEMICAL ELEMENTS IN SOIL FROM THE STRUMICA REGION, REPUBLIC OF MACEDONIA
This study presents results for the distribution of heavy metals in soil samples from the Strumica region, Republic of Macedonia. To perform this study, 132 soil samples were collected (66 from topsoil and 66 from bottom soil). Soil samples were digested by the mixture of mineral acids for total dissolution. Nineteen elements (Ag, Al, B, Ba, Ca, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, P, Pb, Sr, V and Zn) were analyzed by atomic emission spectroscopy with inductively coupled plasma (ICP-AES). The results were statistically processed and maps of spatial distribution of individual elements in the study area were prepared giving the presence of the analyzed elements in soil from the Strumica region. From the obtained results and the distribution maps it can be seen that the higher content of the elements in some areas are mainly due to their presence in the surrounding rocks. Factor analysis is performed from a number of variables providing a small number of new, synthetic variables called factors. On the basis of the spatial distribution of element patterns, comparison of basic statistical parameters, the correlation coefficient matrices, and the results of multivariate (cluster and FA) analyses, three lithogenic associations were established: F1 (Ni-Cr-Fe-V-CuZn), F2 (Sr-Ca-Al-Mg) and F3 (K-Li).