Pilot Scale Use of Compost Combined with Sorbents to Phytostabilize Ni-Contaminated Soil Using Lolium perenne L.

Purpose: An experiment was conducted to evaluate the potential use of a combination of food waste compost with sorbents as immobilizing agents to aid the phytostabilization of Ni-contaminated soil, using Lolium perenne L. (L. perenne). Methods: The content of Ni in plants, i.e. total and extracted by 0.01M CaCl2, was determined using the spectrophotometry method. Tests for the phytotoxicity of food waste compost were carried out using Phytotoxkit tests. Results: The compost phytotoxicity tests showed that the growth of the roots of L. perenne was slightly stimulated for a compost concentration of 25%, showing the positive impact of this material on plant growth. The biomass of L. perenne in particular organs, Ni content and the properties of soil depended on the dose of a Ni contaminant and the type of mineral and organic mixture incorporated into the soil. Conclusions: Ni accumulated predominantly in the roots of the L. perenne. The greatest increase pH was observed after compost with chalcedonite mixture was added to the soil. The application of mineral and organic mixture, containing compost from food wastes and chalcedonite as a soil amendment, tended to reduce the soil total and mobile fraction of Ni more in comparison to the un-amended soil. [GRAPHICS] .