Greenhouse evaluation and environmental impact assessment of different urine-derived struvite fertilizers as phosphorus sources for plants.
A selection of six urine-derived struvite fertilizers generated by innovative precipitation technologies was assessed for their quality and their effectiveness as phosphorus sources for crops. Struvite purity was influenced by drying techniques and magnesium dosage. In a greenhouse experiment, the urine fertilizers led to biomass yields and phosphorus uptakes comparable to or higher than those induced by a commercial mineral fertilizer. Heavy metal concentrations of the different struvite fertilizers were below the threshold limits specified by the German Fertilizer and Sewage Sludge Regulations. The computed loading rates of heavy metals to agricultural land were also below the threshold limits decreed by the Federal Soil Protection Act. Urine-derived struvite contributed less to heavy metal inputs to farmland than other recycling products or commercial mineral and organic fertilizers. When combined with other soil conditioners, urine-derived struvite is an efficient fertilizer which covers the magnesium and more than half of the phosphorus demand of crops.
University of Bonn, Institute of Crop Science and Resource Conservation, Department of Plant Nutrition, Karlrobert-Kreiten Straße 13, 53115 Bonn, Germany. samantha.antonini@yahoo.co.uk7
Samantha
S
Antonini
Maria Alejandra
MA
Arias
Thomas
T
Eichert
Joachim
J
Clemens
D000383:Agriculture / Q000379:methods*; D003198:Computer Simulation; D003247:Conservation of Natural Resources / Q000379:methods; D004784:Environmental Monitoring; D004787:Environmental Pollution / Q000706:statistics & numerical data; D005308:Fertilizers / Q000032:analysis*; D017616:Magnesium Compounds / Q000032:analysis*; D019216:Metals, Heavy / Q000032:analysis; D008956:Models, Chemical; D010710:Phosphates / Q000032:analysis*; D010758:Phosphorus / Q000032:analysis* / Q000378:metabolism; D010944:Plants / Q000378:metabolism*; D012989:Soil Pollutants / Q000032:analysis; D000069877:Struvite; D014556:Urine / Q000737:chemistry*; D014865:Waste Disposal, Fluid
D005308:Fertilizers; D017616:Magnesium Compounds; D019216:Metals, Heavy; D010710:Phosphates; D012989:Soil Pollutants; D010758:Phosphorus; D000069877:Struvite