Integrated Approach of Phytostabilization for Urban Ecosystem Soils Contaminated with Lead

Abstract

The article discusses the creation of a methodological approach and the specific technologies based on it in terms of the phytostabilization of urban soils contaminated with heavy metals, taking into account the peculiarities of urban ecosystems functioning in order to ensure the environmental safety of industrial wastelands. Based on the analysis of existing soil restoration methods, a mechanism for creating an integrated phytostabilization technology was developed by involving the components differing in action, aimed at reducing the migration ability of heavy metals in soil and their translocation into plants. It was suggested to increase the phytoremediation potential of phytostabilizers through the stimulation of internal defence mechanisms of plants, and through additional application of an ameliorant to bind heavy metal cations in soil, as well as through the use of microbiological preparation in order to restore soil protective functions. The practicability of phytostabilization using alfalfa (Medicago sativa) plants combined with detoxification with an aqueous solution of potassium carbonate and the BTU-r multipurpose biocomplex microbiological preparation was experimentally confirmed by means of an example of lead contamination of urban ecosystem soils in the city of Dnipro. It was concluded that their combination provides the lowest Pb²⁺ removal from the soil by alfalfa (Medicago sativa) plants and a significant reduction in the availability of the metal compounds in soil.