Effect of industrial sludge-soil mixtures on germination of white mustard and wheat

Many industrial process produce different kind of sludge as by-product. Those various sludge-types can contain heavy metals or other valuable or reusable elements (as rare-earth metals). Our aim is to determine the accumulation rate of these elements in the plant-tissues and establish the phytoremediaton potential of the plants. Laboratory experiment was conducted in seedling growth tests with various mixtures of red mud, converter sludge and different soil-type-peat mixtures. White mustard (Sinapis alba) and wheat (Triticum aestivum) seeds were applied for the experiments. According to these tests we determined that among the mixtures the most capable ones were the red mud mixed with slightly saline or slightly acidic brown forest soils. In case of the converter sludge, mixtures with chernozem and loess soil showed the best results for germination. The presence of the used sludge-types could stimulate the germination of seeds and the growth of plumules of plants, however the results are highly depends on the type of the soils. The results highlight the importance of seedling tests in determining the phytoextraction possibility when using industrial waste materials, such as the tested sludge-types