不同结构好氧/厌氧潜流人工湿地微生物群落代谢特性

4种不同结构的好氧/厌氧多级串联潜流人工湿地对COD和氮的去除效果不同.为了探究基质微生物群落代谢特征及其与水质净化效果的关系,对利用Biolog微平板得到的AWCD值(平均每孔光密度值)进行碳源分类、主成分分析以及聚类分析.结果表明,微生物对于糖类及其衍生物和氨基酸及其衍生物的利用水平明显高于对脂肪酸及脂类和代谢中间产物及次生代谢物的利用水平;OBAAO(好氧-缓冲-厌氧-缺氧-好氧)曝气组中采样点3.3(厌氧采样点)微生物对4类碳源的利用水平都最低,与其他各采样点具有显著性差异(p<0.05),96hAWCD值主成分分析和聚类分析的结果表明,OBAAO曝气组采样点3.3中的微生物群落和其他3个进行厌氧反应的采样点中的微生物群落发生了较大的差异,OBAAO曝气组延长厌氧段长度为微生物提供厌氧环境,而由于缺少碳源作为能量,使得微生物的活性受到抑制;OBAAO曝气多点进水组中的采样点4.3(厌氧采样点)微生物在4类碳源的利用水平上都具有一定的优势性,OBAAO曝气多点进水组补充进水和延长厌氧段长度两个措施有效地促进了微生物的反硝化作用的强度,提高了水平潜流人工湿地的氮去除率.

Characteristics of microbial community metabolism in aerobic/anaerobic subsurface flow constructed wetland

Four different structures of aerobic/anaerobic subsurface flow constructed wetland had different purification efficiencies for COD and N. To investigate the characteristics of the microbial community metabolism and its relationship with water purification, carbon source analysis, principal component analysis and cluster analysis were used on the average well color development (AWCD) values obtained from the Biolog Ecoplate. The results showed that the degree of microbial utilization of carbohydrate and its derivatives, amino acids and its derivatives were significantly higher than that of fatty acid, lipid, metabolic intermediate and secondary metabolites. The degree of microbial utilization of four kinds of carbon sources in the sampling site (the sampling site which proceeded anaerobic reaction) in the group of OBAAO (aerobic-buffer-anaerobic anoxic-aerobic) aeration were the lowest, and it had significant difference with that of the other sampling sites (p<0.05). The results of principal component analysis and cluster analysis indicated that the microbial community of the sampling site 3.3 in the group of OBAAO aeration had high difference from those of the other 3 sampling sites which were preceding anaerobic reaction.The group of OBAAO aeration extending the length of anaerobic stage provided the anaerobic environment for microorganisms. However, because of the lack of carbon source as energy, the microbial activity was inhibited. The microbial utilization degrees in sampling site 4.3 (the sampling site which proceeded anaerobic reaction) in the group of OBAAO aeration multiple spot influent had certain advantage. The group of OBAAO aeration multiple spot influent, by adding influent and extending the length of anaerobic stage, effectively promoted the strength of denitrification, and increased the removal efficiency of nitrogen within horizontal subsurface flow constructed wetlands.