Every year, trillions of liters of wastewater are treated in sewage treatment plants. What flows out of households, businesses, and industry is processed in three elaborate purification stages. However, current treatment facilities are still unable to remove 100% of all pollutants. As a result, persistent chemicals, microplastics, and pharmaceuticals continue to find their way into bodies of water – and therefore into nature. Researchers at the Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB in Straubing have been working on a solution.
Restoring arable soils with catch crops
Catch crops such as field mustard or legumes are small all-rounders for agriculture: they serve as animal feed or remain on the field as green manure to prepare or improve the soil for the next main crop. In this way, plants are supplied with nutrients, humus formation is promoted, the water, nutrient and carbon balance in the soil is stabilized and erosion is prevented. However, their potential as pollutant removers has so far been underestimated.