Effects of nitrogen recycling by human urine fertilization on butterfly pea (Clitoria ternatea) plant in green wall system on AIT campus

Abstract

The use of wastewater (urine) as a fertilizer was shown to potentially reduce the campus wastewater load and contribute to saving in expensive wastewater treatment, while dealing with it as valuable resource. If one assumed that this wastewater fertilizer (arguably, one of the best agriculturally acknowledged fertilizers), was applied at odor appropriate and physiologically sustainable rates (Nitrogen Loading Rate (NLR) of up to 0.73 g N m-2 week-1 equivalent to 104.28 mL urine m-2 week-1 applied for 16 weeks) and considered total available area for potential green walls, it could be stated that the entire urine stream generated daily on campus (varying from 2.2 to 4.5 m3) could be accommodated on campus green walls as a valuable resource with significant benefits. In the studies on monitored plant physiological parameters under various conditions, it was observed that urine fertilizer positively affected to the food production, inflorescences and health of butterfly pea (Clitoria ternatea) plant as well as could say that it was the most suitable plant for green wall. Further integration of urban wastewater management and agriculture (urban food production) into this scenario can make it even more attractive and economically sustainable.