复合垂直流人工湿地污染物去除特点及微生物群落多样性PCR-TGGE分析

Analyses on the Pollutant Removal Characteristics and Microbial Community Diversity in Integrated Vertical-Flow Constructed Wetland

采用复合垂直流人工湿地系统对生活污水进行处理，研究该系统对污水中主要污染物的去除效果，并采用PCR-TGGE技术分析了湿地系统中微生物群落结构组成的多样性。结果表明，污染物浓度沿水流方向呈下降趋势，氨氮（NH4-N）.总氮（TN）.总磷（TP）和生化需氧量（COD）平均去除率分别为59.5％、67.5％、75.6％、62.3％。溶解氧（DO）沿程逐渐降低，但在末端略有上升，pH基本维持在7.72～8.04，污染物去除效果良好；由于湿地系统中环境条件和营养水平的变化，系统中不同位置微生物种群存在共同种属和各自的特异种属，且微生物多样性指数从A1池至A3池沿程逐渐降低，群落结构间的相似性逐渐增大；系统中污染物去除与微生物多样性呈正相关关系。

The technology of integrated vertical-flow constructed wetland （IVCW） was used to treat domestic sewage. Its efficiency of removing major pollutants was studied, and the diversity of microbial community structure in IVCW was analysed with polymerase chain reaction and consecutively performed temperature gradient gel electrophoresis （PCR-TGGE） technique. The results indicated that the levels of ammonium nitrogen, total nitrogen, total phosphorus and COD, declined along the direction of water flow in IVCW and their average removal rates were 59.5%, 67.5%, 75.6% and 62.3%, respectively. The dissolved oxygen level also decreased gradually along the way whilst a little rising at the end of A3. The pH value maintained in the range of 7.72 to 8.04 in slightly alkaline condition, meanwhile it had good pollutant removal efficiency. Since environmental condition and nutrition changed in wetland systems, there existed some common species and each distinctive species at different locations, microbial diversity index decreased along the direction of water flow from A1 to A3 in IVCW, and the similarity among community structures gradually increased. Its pollutant removal efficiency in the system was positively correlated with the microbial diversity.