Samarska A. Increasing the level of ecological safety of railway zones due to reducing the adverse impact of heavy metals on the environment

The thesis is devoted to the decision of a topical scientific and applied challenge of increasing the level of ecological safety and reducing adverse impact of heavy metals on the environment in the conditions of the railway transport operations. According to the work results, a comprehensive ecological assessment of granite ballast crushed stones as a primary and secondary source of heavy metals on railways is presented. The main pollutant metals at a passenger station have been identified. The significant positive correlations were found between the content of Fe, Ni, Cr and Mn in the contaminated ballast layer, which indicates the homogeneity of the formation source. These metals are traditional components of stainless steel. A detailed evaluation of glyphosate-based herbicides as a source of heavy metals was performed. Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn were detected in all the herbicide samples. According to the study results, herbicides are classified as an insignificant source of these dangerous elements. The technology of ecological control of undesirable vegetation on railways is offered, which is closely connected with phytostabilization of the soil for further reducing erosion and formation of wind dust. The scientific principles of the phytostabilization on the lands of the railway infrastructure have been developed, taking into account the technical peculiarities of the railway operation and maintenance. The right of way zones have been differentiated according to the scale of phytostabilization and the level of undesirable vegetation control. The main advantage and feature of the thesis research is the development of comprehensive measures to increase the level of environmental safety by reducing environmental contamination with heavy metals and herbicides, as well as increasing man-made safety by strengthening the slopes of railway embankments and cuttings, ensuring the reliable wheel-rail adhesion and maintenance of the ballast layer condition. Keywords: ecological safety, railway transport, heavy metals, pollution, ballast layer, right-of-way, phytostabilization, traffic safety, herbicides.