EVALUATION THE MICROELEMENTS AND HEAVY METALS CONTENT IN THE CONDITIONS OF SOME AGRICULTURAL AND FOREST LANDS

Abstract

The study analyzed and evaluated the content of some microelements and heavy metals in the conditions of two categories of agricultural and forest land. The study location was in the "Padurea Cenad" Protected Area and the bordering agricultural area, Timis County, Romania. Among microelements, the content of iron (Fe, ppm), manganese (Mn, ppm), copper (Cu, ppm) and zinc (Zn, ppm) was analyzed, and among heavy metals, the content of chromium (Cr, ppm), nickel (Ni, ppm) and lead (Pb, ppm) was analysed. The ANOVA test was used to quantify the statistical reliability of the data, and to evaluate the presence of variance in the data set (Alpha=0.001). The correlation level of the determined microelements and heavy metals was evaluated by correlation analysis (Pearson), and the statistical safety was evaluated based on p parameters (p <0.05; p <0.01; p <0.001). Correlations of different intensity levels were recorded between the analyzed elements (eg r=0.914 between Fe and Cu; r=0.916 between Fe and Ni; r=0.935 between Mn and Zn; r=0.933 between Mn and Cr; r= 0.920 between Zn and Cr; r=0.990 between Ni and Pb; r=0.851 between Fe and Pb; r=-0.732 between Mn and Ni; r=-0.731 between Mn and Pb). A high level of variability was recorded in the case of Pb content (CVPb=43.8455), and a low level of variability in the case of Mn content (CVMn=8.1807). Intermediate values was recorded in the other cases, CVCr=25.4583, CVNi=23.9941, CVCu=23.0055, and CVFe=21.0282 respectively. According to PCA, PC1 explained 70.240% of variance, and PC2 explained 22.469% of variance. Separate positioning in relation to the content of microelements and heavy metals (as biplot) was found at CP1-A and CP2-F. Associated with the content of Mn, Zn and Cr (as biplot) CP2-A was positioned, and associated with Fe, Cu, Ni and Pb (as biplot) CP1-F was associated.