Minimized nutrient leaching through fertilizer management : an evaluation of fertilization strategies

Abstract: Nutrient leaching causing surface- and groundwater pollution and eutrophication is one of the main environmental problems of modern society. Plant production is among the quantitatively most important sources of nutrient leaching, particularly of nitrogen and phosphorus, which stands in focus in remediating these problems. One of the most important measures to be taken is to apply fertilizers in a correct way to meet the needs of the plants while preventing any nutrients to leach. The rather unnoticed theory and method of the demand-driven fertilization strategy, which means to supply the plant with nutrients according to its momentary demand, was compared with representative fertilization strategies commonly used in current commercial plant production. Then the demand-driven driven strategy was compared with three other strategies in a pot experiment: (1) a linear nutrient supply on a daily basis, (2) an approximately linear nutrient supply added twice a week, and (3) a onetime application with all the fertilizers added in the beginning. Uptake and leaching of N and P was measured for all treatments. The results clearly showed that the demand-driven strategy leached the least and had the highest uptake in relation to the added amount of N and P, and that the onetime application leached the most. It was concluded that the demand-driven strategy had highest potential in amending nutrient leaching, and that further studies most likely would be fruitful.