Growing miscanthus on radioactively contaminated soils and regularities of 137 CS redistribution in the system «Soil-Plant-Lysimetric waters»

Abstract

Purpose. Investigate the patterns of transition of 137 Cs radionuclide from soil to biomass and lysimetric waters depending on the elements of technology for growing giant miscanthus on solid fuel on contaminated soils.
 Methods. Lysimetric, biomorphological, radiometric, statistical, comparative and computational.
 Results. The article presents the results of research to study the accumulation of the radioactive isotope 137 Cs in the biomass of giant miscanthus and its transition into lysimetric waters. According to the research results, the level of 137 Cs radionuclide accumulation in miscanthus plants on contaminated soils depends on its concentration in the soil and elements of cultivation technology. It was found that in the variants where the bioenergy crop was grown on soils contaminated with radionuclides, the accumulation of 137 Cs in the biomass in the range of 14.7–18.6 Bq/kg and in the lysimetric waters of 4.36–4.57 Bq/l was observed, respectively. Fertilization with mineral fertilizers together with defecation and treatment with miscanthus rice before planting with the microbial preparation Polymyxobacterin in combination with BioMAG helped to increase the yield of dry biomass by 28% of control.
 Conclusions. The use of mineral fertilization in combination with liming, inoculation of miscanthus rhizomes with the microbial drug Polymyxobacterin and pre-planting treatment with organo-mineral fertilizer BioMAG significantly increases the yield of dry biomass, reduces the content of 137 Cs in biomass and lysimetric waters. The accumulation of 137 Cs in the biomass of miscanthus when grown on soils contaminated with radionuclides did not exceed the permissible level (DR), and the use of elements of technology helped to reduce the content of 137 Cs by 12–21% compared to control variants. The use of the fertilizer complex «mineral fertilizers + defect + Polymyxobacterin + BioMAG» resulted in the lowest accumulation coefficients of 137Cs, which are 0.07 in the biomass of miscanthus and 0.02 in lysimetric waters, respectively.