Bioremediation of Copper- and Chromium-Contaminated Soils Using Agrostis capillaris L., Festuca pratensis Huds., and Poa pratensis L. Mixture of Lawn Grasses

Environmental pollution by toxic metals is a common ecological problem. Chromium and copper compounds released into the environment as a result of human-made stress pose a serious threat to living organisms. Phytoremediation is a promising method of toxic metals removal from contaminated sites. The concentration of metals in grass biomass-in the roots and aerial parts-was determined by X-ray fluorescence analysis. The estimation of numbers of microorganisms was conducted by a tenfold dilution and spread-plating method. It was shown that lawn grass accumulated from 69.1 +/- 13.2 to 497.7 +/- 74.1 mg/kg Cu and Cr during the growth in the contaminated soil with 50, 100, and 200 mg/kg of metals. In general, there was a pattern of accumulation of copper in the aerial part of the grass and chromium in the roots. Thus, the total copper concentration in the aerial part ranged from 105.2 +/- 23.8 to 497.7 +/- 74.1 mg/kg of plant biomass. The total chromium concentration in the roots ranged from 156.4 +/- 47.9 to 426.8 +/- 62.5 mg/kg. The viability of the soil microbiome was not inhibited at such metal concentrations. The obtained data allow lawn grass to be considered as promising for the phytoremediation of contaminated areas.

Automated summary

The study demonstrates that lawn grass can accumulate copper and chromium in contaminated soil without inhibiting the viability of soil microbiome, making it a promising candidate for phytoremediation in contaminated areas.