ABSTRACT
Nitrogen (N) dynamics in geochemical processes maintain the living systems in the biosphere on our planet. Application of nitrogen fertilizers in agriculture resulted in significant yield increases during the last century. However, the side effect of nitrogen fertilization is an increased potential for nitrogen leaching, which may cause contamination of groundwater and surface waters. The water hyacinth roots can stimulate microbes in the processes of nitrification and denitrification to promote biological nitrogen removal from water bodies. Researchers have focused on water hyacinth biology, utilization and weed management and facilitated application of the macrophyte in purification of eutrophic water contaminated with nutrient runoff or leaching from farm land and also in treatment of sewage and aquaculture wastewater, achieving nitrogen removal rate of up to 80%. Furthermore, nitrogen assimilation by water hyacinth is often associated with available phosphorus, so in assessing nitrogen removal efficiency, available phosphorus must be taken into consideration.
