Biogeochemical characteristics of parks and public gardens in Rostov-on-Don

The distribution of heavy metals and arsenic in the soils and leaves of the locust in the parks and squares of Rostov-on-Don was studied. 81 samples of soil and 30 samples of leaves were selected in 13 parks of the city. To determine the concentrations of elements, we used the approximate-quantitative and atomic-absorption analyses. For all elements, the concentration coefficient was calculated, as well as the hazard factor representing the multiplicity of exceeding the MAC or AAC. The total pollution index (Z_c), which is the sum of the excess concentrations of individual elements above the background level, was used to characterize complex pollution. When comparing the average concentrations of metals and arsenic with the natural pedogeochemical background, a geochemical association is revealed: Cu₂ˏ₅Zn₂ˏ₃Pb₁ˏ₈V₁ˏ₃Hg₁ˏ₃Ni₁ˏ₂Cd₁ˏ₂, typical of Rostov-on-Don soils. Weakly local pollution of soils of parks and squares with zinc, copper, vanadium and lead was revealed. The most common pollutant is zinc, for which the highest excess of AAC is characteristic. Pollution of the soil cover of recreational areas is assessed as permissible. With the passage of time, the concentration of zinc decreases and the concentrations of copper and vanadium increase in the soils of park landscapes. There has been increasing biological absorption by the leaves of the locust copper and molybdenum.