Effective control of eutrophication is generally established through the reduction of nutrient loading
into waterways and water bodies. An economically viable and ecologically sustainable approach to
nutrient pollution control could involve the integration of retention ponds, wetlands and greenways
into water management systems. Plants not only play an invaluable role in the assimilation and
removal of nutrients, but they also support fauna richness and can be aesthetically pleasing. Pandanus
amaryllifolius, a tropical terrestrial plant, was found to establish well in hydrophytic conditions and
was highly effective in remediating high nutrient levels in an aquatic environment showing 100%
removal of NO−
3 -N up to 200 mg/L in 14 days. Phosphate uptake by the plant was less efficient with
64% of the PO−
4 -P removed at the maximum concentration of 100 mg/L at the end of 6 weeks.
With its high NO−
3 -N and PO3−
4 -P removal efficiency, P. amaryllifolius depleted the nutrient-rich
media and markedly contained the natural colonization of algae. The impediment of algal growth
led to improvements in the water quality with significant decreases in turbidity, pH and electrical
conductivity. In addition, the plants did not show stress symptoms when grown in high nutrient levels
as shown by the changes in their biomass, total soluble proteins and chlorophyll accumulation as
well as photochemical efficiency. Thus, P. amaryllifolius is a potential candidate for the mitigation of
nutrient pollution in phytoremediation systems in the tropics as the plant requires low maintenance,
is tolerant to the natural variability of weather conditions and fluctuating hydro-periods, and exhibit
good nutrient removal capabilities.
Introduction
Eutrophication caused by excess nutrient loads is one of
the common problems in surface waters globally. Excessive
nutrients, primarily nitrogen (N) and phosphorus
(P), arise from rapidly expanding urban development as
well as intensifying agricultural and industrial activities.
Restriction of nutrient loading is the essential key to
eutrophication control. Phytoremediation presents a cost
effective and ecologically sustainable way of reducing high
nutrient inputs to water bodies by treating point and non-
∗ corresponding author. E-mail: dbsongbl@nus.edu.sg
point source pollution. Removal of N and P using aquatic