Plants inhabiting polygons for megapolis waste as promising species for phytoremediation

Screening of ruderal plant species inhabiting polygons for solid waste (SW) burying contaminated with heavy metals (HM). Among these plants, wood small-reedgrass (Calamagrostis epigeios L. Roth) was found; this plant is a perennial grass characterized by the highest level of HM, especially Ni, accumulation. The content of Ni was 703 mg/kg dry wt in wood small-reedgrass leaves and 346 mg/kg dry wt in its rhizomes. On the SW polygon closed 15 years ago, wood small-reedgrass produced a monoculture of high productivity (15 centner/ha), and this provided for extraction of HM moved from SW layers and maintenance of their concentrations in covering soil at the level not dangerous for plants (by 5–10 times below the threshold level). Under constant conditions, the tolerance of wood small-reedgrass seed germination to HM was established. Adult plants turned out to be tolerant to periodic mowing; they were capable of HM accumulation in above-ground organs; they also accumulated the osmorprotectant proline. It was concluded that wood small-reedgrass could be used for SW polygon recultivation and within the lawn grass mixtures for near-road lawns in cities.