人工湿地系统去除藻毒素研究

以含水华的鱼塘水作为进水灌溉两套上行流－下行流人工湿地系统,系统内种植芦苇等水生植物。灌溉一周后收集人工湿地进出水水样,用ＨＰＬＣ法检测其藻毒素定量,结合温度、电位、溶氧等理化指标和细菌、藻类数量的变化,分析人工湿地系统对藻毒素的去除效果及影响其效果的可能因素。结果表明,人工湿地系统对藻毒素有一定的去除效果优于茭白－石菖蒲组合的湿地系统。在三种主要藻毒素ＲＲ、ＹＲ、ＬＲ中,湿地对ＹＲ的去除效果最好

STUDY OF THE EFFECT OF CONSTRUCTED WETLAND ON THE REMOVAL OF MICROCYSTINS

Two sets of downflow-upflow constructed wetland systems planted with different macrophytes were irrigated by water with algae bloom for one week. The inflow and outflow of the constructed wetlands were collected to study the removal efficiency of microcystins of the constructed wetland. The content of microcystins were tested by HPLC; the values of temperature, conductivity and dissolved oxygen were also determined,as well as the content of microcystins and microorganism in the water sample. Results showed that the two constructed wetland systems could reduce the microcystins in the inflow with the removal rates of 68.5% and 34.6% respectively. The removal efficiency of the wetland planted with Phragmites australis and Schoenoplectus sp. were better than the wetland planted with Zizania latifolia and Acorus tartarinowii.Among the three kinds of microcystins(RR, YR and LR), the YR is best removed by the constructed wetlands;its content dropped to lower than the test limit. Sorbing by the substrate and degrading by the microbes were the two main processes of the microcystins' removal in constructed wetland, and the microbial process, being largely affected by the conductivity and bacteria activity in the wetland,is more important.