人工湿地氧化还原特征及其与微生物活性相关性

在水力负荷为800 mm/d的运行条件下,研究了复合垂直流人工湿地中试系统不同功能层面的氧化还原特征、好氧微生物数量、基质的耗氧速率及氧化还原酶类活性的分布特点。结果表明:各功能层面的氧化还原电位、好氧微生物数量、耗氧速率表层最高,并且随着基质深度的增加逐渐降低。除过氧化物酶外,氧化酶活性表现为表层高于中下层;而硝酸盐还原酶、亚硝酸盐还原酶等活性变化趋势则相反。同时,氧化还原电位与基质中细菌、真菌、放线菌的数量、耗氧速率等存在显著正相关关系;氧化还原电位与多酚氧化酶、过氧化氢酶、脱氢酶等氧化酶活性也存在显著正相关,而与下行流池的硝酸盐还原酶、亚硝酸盐还原酶等还原酶类存在显著负相关关系。

Correlations between the Redox Potential Characteristics and Microorganisms Activities in the Integrated Vertical Flow Constructed Wetland

Under the 800 mm/d of hydraulic loading,the redox potential characteristics,the numbers of aerobic microorganisms,oxygen consumption rates,the distribution of oxidoreductase activities of different layers in the medium scale plot system of the integrated vertical-flow constructed wetland(IVCW) were studied.The results were as follows: The redox potential,numbers of aerobic microorganisms and oxygen consumption rates were highest in the surface layer,and gradually decreased with substrate depth.The activities of oxidases in the surface layer were generally higher than those in the middle and lower layers except peroxidase;while the change trends of nitrate reductase and nitrite reductase activities were reverse.There were significantly positive correlations between the redox potential and the number of bacteria,fungi,actinomycetes and oxygen consumption rates;there were also significantly positive correlations between the redox potential and the activities of polyphenoloxidase,catalase,dehydrogenase.Meanwhile,there were significantly negative correlations between the redox potential and nitrate reductase,nitrite reductase activities in the down-flow chamber.