Bara Bihari Jana and his colleagues tried growing several Moina micrura (a zooplankton species commonly fed to hatchling fish in fisheries) stocks in a variety of different feces/urine cocktails, including cow urine and dung and poultry droppings. Those that were reared on human urine started reproducing at least four days earlier, lived longer and produced more offspring than the rest. "Human urine is a stable liquid and contains valuable nutrients. I see no reason why it couldn't be used for this purpose if it provides a suitable chemical environment for the zooplankton to grow," said Stephen Smith, an environmental biochemist at Imperial College London.Why makes human urine such an effective fertilizer? According to Jana, in addition to containing high concentrations of nitrogen compounds, its rapid degradation prompts a "quick release of nutrients" that "induced the fast reproduction in the plankton."
Not surprisingly, human urine is much cheaper to "produce" and is more eco-friendly than chemical fertilizers, whose frequent use often results in severe bouts of eutrophication. As a result, it could provide a cost-effective solution to the needs of the multi-billion dollar planktonic culture industry and, in turn, could prove tremendously beneficial to the large commercial fisheries industry.
For many of the same reasons that it has shown itself to be such an effective fertilizer for zooplankton, human urine also has tremendous potential as an agricultural fertilizer, though worries about disease transfer and the presence of antibiotics and hormones may hinder its widespread use. Jana and his colleagues didn't have any problems using it to feed the zooplankton. "We have not yet encountered any diseases or abnormalities in the zooplankton grown in tanks with human urine, but we are looking for hormone residues and antibiotics, just to be sure" he said.
Cheap, natural and environmentally friendly: just the way we like it.
Via ::Nature: Urine grows better fish food (magazine)