Statistical Analysis of the Influence of Heavy Metals in the Soil on the Biometric Parameters of Plants as a Consequence of Military Actions

Methods of assessing the intensity of plant growth in soils contaminated with elements of heavy metals as a result of military operations can provide important data regarding the migration, bioavailability of chemical compounds for plants, as a result of the formation of chemical compounds, which are key parameters for assessing the phytoremediation potential. The use of various methods of assessing the impact of heavy metals in the soil on plant growth can be evaluated not only based on the degree of environmental risk, but also predict the magnitude of the impact of a complex of chemical elements taking into account synergistic factors based on a statistical assessment based on the Pearson and Spearman complex. It was established that the mutual influence on the formation of active compounds in the soil significantly affects the intensity of plant growth and, accordingly, the negative correlation of the Pearson coefficient with the concentration of heavy metals in the soil for such as Cd, Cr and Ni. A positive correlation in the range of 0.75-0.89 is typical for soil samples with copper, lead, zinc and titanium. The impact of potentially toxic elements on the biometric parameters of plants was determined using germination tests. Slowdown of plant growth in the range of 5-10% was observed for soils with excess content of elements in the following sequence: zinc, lead, nickel, copper, chromium, cadmium and titanium.Statistical analysis was performed based on the results of biometric parameters of plants from germination tests. The application of the t-test (Shapiro-Wilk, p>0.05) established statistical differences in the homogeneity of the dispersion and the normality of the distribution. Under the condition (p=0.05) of normal distribution, the Mann-Whitney test was used. At p>0.05, the Brown-Forsyth test was used to analyze homogeneity of variances with a normal distribution. The use of the Welch test made it possible to establish the fact whether the distribution is normal for homogeneous and heterogeneous dispersion. Based on the Statistica 13.1 program, it was established that the Welch test data confirm the normal distribution of various types of variance.