Фитотоксичность почвосубстратов на основе шлаков металлургического производства, используемых в рекультивации

Abstract

The aim of the study. To estimate the influence of various metallurgical slags on the initial stages of plant growth and development. The study location and time. Vegetation experiment was conducted in laboratory where during 2 weeks plants were grown on mixed soil-slag substrates under favourable air temperature and humidit, substrate moisture and illumination rate of 1500 lux. Methodology. To conduct phytotoxicity testing we followed the protocol described by the federal standard GOST R ISO 22030-2009, using one species of the monocotyledonous plants (oats Avena sativa L., cultivar “Rovesnik”) and one species of dicotyledonous plants (radish Raphanus sativus var. Sativus, cultivar “Saksa”). Four slags produced at the EVRAZ West Siberian plant by different technologies were used: white non-ferrous, blast furnace, converter and electrofurnace ones. The concentration of slags in soil-slag mixtures used as growth substrates, were 0 (soil);12.5; 25; 50 and 100% (pure slag). The data obtained were analyzed by descriptive statistics and correlation analysis. Main results. The growth and development of both radish and oats plants were not impeded by electrofurnace slag in all concentrations tested. The white non-ferrouswas found to be phytotoxic for both species in high concentrations only (50 and 100%). The converter and blast furnace slags had phytotoxic effect on radish only in their pure form, while for oats growth these slags were found to be harmful at 50% concentration. Conclusion. At the initial stages of plant growth and development three of the four studied metallurgical slags were found to have phytotoxic effect only in very concentrations in the substrates. Therefore to develop perspective technologies of slag use in recultivation we recommend to conduct longer vegetation and field experiments with lower slag concentrations for growing plants that can be really used for specific recultivation purpose, e.g. mixtures of legumes, grains and herbs, as well as woody bushes.