Landfill leachate treatment by oleaginous plants

Plant utilization for landfill leachate treatment is considered a possible alternative to less sustainable systems. In order to evaluate phytotreatment efficiency, three oleaginous plant species, Helianthus annus, Glycine max and Brassica napus, were grown in pots filled with sand. Half pots were treated for three months with diluted leachate at increasing nitrogen concentration. The remaining pots were treated with nutrient solution. Promising results were obtained by the leachate phytotreatment process. The plants growth was positively affected by leachate irrigation, although a lower shoot biomass of soybean and rapeseed plants compared to controls was observed. High nitrogen removal efficiencies were obtained for the three plant species during the first 8 weeks of treatment. In the last 4 weeks, plants underwent to the senescence phase and the capacity of nitrogen absorption was consequently reduced.