Soil toxicity reduction by phytoindicators

Abstract

The grass mixtures use in phytoremediation is poorly studied, so we have proposed some options for new plant species that can grow on polluted land and accumulate pollutants with aboveground biomass. In heavy soil contamination case with heavy metals, we suggest using annual plants with large biomass in the recultivation first year, which can remove up to 50% of the pollutant from the biological cycle in the first year. Studying plants on toxic soils, we determined their accumulating capacity and used them as phytomeliorants. In several experiments, indicator plants were used: amaranth, clover, alfalfa, elm, stevia, ragweed, winter camelina mixed with an annual type of clover, and others, which, with the maximum biomass accumulation, were plowed into the soil in a mixture with zeolite-containing clays of local importance. The experiments result showed that with the indicator plants help it is possible not only to improve soil fertility, but also to significantly reduce the heavy metals and oil products amount. Organic waste from agricultural production was also of great importance in reducing soil toxicity: corn cobs, sunflower baskets, and leaf litter embedded in the soil with biological products. To activate the plowed organic mass, para-aminobenzoic acid (PABA) was used. The experiments result showed a significant decrease in toxicants in the soil when using organic waste and plowing plants as a green fertilizer in a mixture with zeolite-containing clays and biological products.