Nutrient removal in constructed microcosm wetlands for treating polluted river water in northern China

River water pollution is increasingly widespread in northern China and can lead to problems with the drinking water for the residents if not properly treated. Constructed wetlands are a promising solution and have become increasingly popular in China. In this study the nutrient removal and plant uptake in constructed microcosm wetlands vegetated with Typha orientalis, Phragmites australis, Scirpus validus and Iris pseudacorus for treating simulated polluted river water in northern China were investigated. The performance of the treatment systems from April to November was assessed. The maximum TN, NH 4-N and TP removal efficiencies were 68%, 93% and 67%, respectively. And the maximum nutrient uptake by plants constituted 51.89% of the N removal and 34.17% of the P removal throughout the trial. S. validus and I. pseudacorus have a higher nutrient uptake capacity and are preferred species from a treatment perspective in constructed wetland in northern China.