Phytoremediation performance of mixed planting patterns and the associated rhizosphere microbial community in pilot-scale constructed wetlands.

Phytoremediation is a low-cost, environmentally friendly, and sustainable technology that can utilize vegetation and microorganisms to avoid eutrophication and purifying water environment. The ability of five different living aquatic plants of nitrogen (N), phosphorus (P), and chemical oxygen demand (COD cr) removal were investigated in pilot scale constructed wetlands (CWs). Aquatic plant mixes significantly improved COD cr removal and plant tissue uptake of nitrogen and phosphorus. The wetland performance of mixed plantings was also influenced by the specific species. The mixed planting of Phragmites australi, Nymphaea Colorado and Myriophyllum verticillatum (PNM)When assessing pollutant removal in CWs, PNM performed better within mixtures, a possible synergistic effect, while TNV Typha orientalis, Nymphaea Colorado, and Vallisneria natans (TNV) performed poorly, a possible antagonist effect. The nutrient uptake within plant tissues byunder mixed plants planting was always ahad synergistic effect. Mixed plantingAquatic plant mixes significantly increased the rhizosphere microbial diversity and promoted the growth of functional denitrifying flora. [Display omitted] • Mixed planting significantly promoted CODcr removal, but had no effect on nitrogen and phosphorus removal. • Mixed planting of plants were always synergistic on plant uptake of nitrogen and phosphorus. • Mixed planting significantly increased the rhizosphere microbial diversity and promoted the growth of denitrifying flora. • Selecting the right mix of plants is an effective means to enhance the efficiency of CWs and improve eutrophication. [ABSTRACT FROM AUTHOR]