不同植物种类、碳氮源供给和pH对人工湿地真菌反硝化的影响

【目的】认识碳、氮和pH及其与植物的交互作用对垂直流人工湿地真菌反硝化作用的影响，为真菌反硝化作用的调控提供依据。【方法】采用4种常见的水生植物（黄菖蒲、美人蕉、水葱和伞草），在20个垂直流人工湿地中设置了4种单独栽培处理。运行5个月后，分别从20个湿地中收集0-30 cm的细砂样品，利用微宇宙培养的方法，检验不同碳源、氮源补充和pH梯度对细砂样品中真菌反硝化潜力的影响。【结果】双因素方差分析表明，垂直流人工湿地中碳源、氮源与植物种类之间的相互作用对真菌反硝化潜力作用不明显（P 0.05），而pH与植物种类之间的相互作用对真菌反硝化潜力作用显著（P 0.05）。7种碳源中的葡萄糖和琥珀酸钠的应用最能促进湿地填料中真菌反硝化潜力的提高（P 0.05），而在4种氮源中亚硝酸钠是最能提高真菌反硝化潜力的氮源（P 0.05）。与未进行酸碱处理（pH 6.89）相比，调节pH到2.8显著降低了真菌反硝化潜力（P 0.05），而调节pH到5.6或8.4均不同程度地提高了真菌反硝化潜力。【结论】本研究突出了葡萄糖、琥珀酸钠和亚硝酸盐在调节真菌反硝化潜力中的重要性，并发现在pH 5.6~8.4范围内，湿地填料中的真菌反硝化潜力较大。

Effects of plant species,carbon and nitrogen amendments and pH on potential fungal denitrification in constructed wetlands

Objectives] To provide guidelines for controlling fungal denitrification in constructed vertical flow wetlands,some factors affecting the fungal denitrification were investigated.Methods] Four monocultured treatments were set up using four macrophyte species (Iris pseudacorus,Canna glauca,Scirpus validus and Cyperus alternifolius) in twenty simulated vertical flow constructed wetlands.After wetlands were operated for five months,fine sand samples were collected from 0-30 cm depth of wetlands,and effects of carbon and nitrogen amendments and pH gradient on potential fungal denitrification were tested using a room-incubating method.Results] The two-way ANOVA (analysis of variance) indicated that the interactions between carbon or nitrogen amendments and plant species did not significantly affect the potential fungal denitrification (P ＞0.05),while the interactions between environmental pH and plant species significantly affected the potential fungal denitrification (P ＜ 0.05).Among seven carbon compounds,applications of both glucose and sodium succinate mostly improved the potential fungal dentrification in the wetland filled materials (P ＜ 0.05),whereas among four nitrogen compounds,sodium nitrite was the best nitrogen compound in enhancing the potential fungal denitrification (P ＜ 0.05).Compared with the treatments unamended with acid or alkaline,the treatment with pH 2.8 significantly decreased the potential fungal denitrification,whereas the treatments with pH 5.6 or 8.4 significantly increased the potential fungal denitrification to different extents.Conclusions] The study highlights the importance of glucose,succinate and nitrite in enhancing the fungal denitrification potential,and the pH range of 5.6 to 8.4 for active fungal denitrification.