Selected Properties of Soil-like Substrates Made from Mine Coal Waste and Their Effect on Plant Yields

Abstract

To reduce the environmental damage caused by coal waste landfills, it is necessary to look for rational methods for their management. One method for their development is the creation of soil-like substrates. This study aimed to assess the properties of soil-like substrates from coal mining waste, combined with a varied sample of sewage sludge and waste mineral wool. The properties of the substrates were evaluated in a pot experiment. The properties of the substrates and their yield potential were determined. Coal mining waste as a substrate, compared to anthropogenic soil, was characterized by a significantly higher sorption capacity; the content of alkaline cations and pH; significantly higher contents of organic carbon, nitrogen, and available forms of K and Mg; and a lower content of available P. The substrates enriched with sewage sludge showed a significant increase in content of organic carbon, nitrogen, and assimilable forms of P and Mg, as well as the optimization of sorption properties. Extending the composition of substrates with mineral wool resulted in further improvement of their properties. The yields of plants grown on coal mining waste were significantly lower than those of those grown on anthropogenic soil. Substrates with sewage sludge and mineral wool had a significantly higher yield potential.

Analysis of Heavy Metal Contaminants and Mobility in Sewage sludge-soil Mixtures for Sustainable Agricultural Practices

“…While the average concentration of trace elements can provide some insight, it is insufficient for a comprehensive assessment of the potential risks associated with natural sludge utilization. This is due to the fact that heavy metals can migrate through soil layers and infiltrate groundwater and surface waters, ultimately contaminating plants and becoming a potential source of harm to humans [11,12]. The mobility of heavy metals largely depends on their chemical composition in the environment and the soil conditions, especially the pH [12,13].…”

“…This is due to the fact that heavy metals can migrate through soil layers and infiltrate groundwater and surface waters, ultimately contaminating plants and becoming a potential source of harm to humans [11,12]. The mobility of heavy metals largely depends on their chemical composition in the environment and the soil conditions, especially the pH [12,13]. Figure 1 illustrates the practices related to wastewater sludge in various EU countries, while Table 1 presents the limits regulating the possibility of using wastewater sludge for natural purposes.…”