Interactions between rhizosphere microorganims and spontaneous plant species inhabiting smelter wastelands

Processes of spontaneous vegetation of toxic smelter waste deposits are slow. However permanent plant cover, effectively limiting dispersion of metals, should be based both on introduced grasses and spontaneous species to ensure greater plant diversity and resistance of such ecosystem. The role of microorganisms in colonizing smelter wastelands by plants has not been sufficiently understood. The growing conditions for both plants and microorganisms in such waste are extremely harsh due to the high content of heavy metals and deficit of nutrients and water. The aim of the work was to assess interactions between microorganisms and most frequent spontaneous plants inhabiting a waste deposit in Piekary, Poland. The samples were collected in the summer of 2018 from rhizosphere of 8 plant species inhabiting the waste pile: 1. Thymus serpyllum; 2. Silene vulgaris; 3. Solidago virgaurea; 4. Echium vulgare; 5. Rumex acetosa; 6. Verbascum thapsus; 7. Solidago gigantea; 8. Eupatorium cannabinum. The samples were subjected to analyzes of enzymatic activity, abundance of microorganisms, functional (System Biolog) and genetic diversity(NGS), physicochemical properties (pH, metal content and solubility, nutrient content) and subsequently compared with the unplanted reference samples. Plant samples were analyzed for metals ans nutrient contents.