Effects of Domestic Sewage on the Photosynthesis and Chromium Migration of Coix lacryma-jobi L. in Chromium-Contaminated Constructed Wetlands

To investigate the effects of domestic sewage on photosynthesis and chromium migration plants in chromium-contaminated constructed wetlands, small vertical flow wetlands Coix lacryma-jobi L. were set up. These used to treat wastewater containing 0, 20, 40 mg/L hexavalent (Cr (VI)), prepared with (DS), 1/2 Hoagland nutrient solution (NS), (DN), respectively. The aim was indicators, such as plant growth accumulation. results follows: (1) Plant heights significantly inhibited under 20 Cr (VI) treatments, stem diameters not affected. use treatment alleviated inhibition (2) Indicators root activity, photosynthetic gas exchange, chlorophyll fluorescence properties decreased increase concentration. values these exchange parameters DN greatest, followed by NS DS. On 70th day treatment, net rate (Pn) higher than that DS treatments. (3) Glutathione (GSH) content roots, stems, leaves increased concentration, it more treatments treatment. (4) With same highest, DN. total substrate NS. (5) addition reduced water sample organic matter content. accumulation substrate, absorption plants, GSH leaves, damage thus benefited ensured sustainable stable operation wetlands.