Abstract
The aim of this study was to investigate the soil condition of recreational park areas in Dnipro city on chromium, nickel and cobalt contents and the ability of various components of black locust’s aboveground biomass to accumulate these contaminants. An excess of the maximum permissible concentration (MPC) of chromium (2.1-4.3) and nickel (1.5-3.5) was recorded in the studied soils of recreational plantings in all experimental sites. Cobalt concentrations exceeded MPC only in two experimental sites: Oles Honchar Dnipro National University Botanical Garden and Green Grove Park (1.4-1.5). It was compared the metal concentrations in the vegetative (leaves, trunk) and generative (fruits) organs of R. pseudoacacia and in the soil beneath a tree canopy of the plantings. Chromium concentrations in aboveground biomass corresponded to the range of 0.10-11.67 mg·kg-1, the highest concentration of this metal occurred in assimilation fraction. The highest accumulation of nickel was recorded in fruits, where its highest concentration was equal to 8.46 mg·kg-1. Cobalt had the lowest concentration values among the metals studied; the range of its content was 0.09-0.21 mg·kg-1, and it had almost the same concentration level in the biomass of trunk wood, leaves and fruits. The biological accumulation factor (BAF) was calculated to determine the deposit potential of R. pseudoacacia. According to the obtained values of BAF, it should be noted that bioconcentration was not occurred for all the studied metals. R. pseudoacacia is able to function optimally in urban soils of park areas with a rather wide ranges of chromium, nickel and cobalt concentrations. Due to low values of BAF, this tree species is not susceptible to accumulate the metals in such concentrations that can pose a risk for the use of this species in recreational plantings of industrial city parks