Author(s): Xie Yuxuan, Liu Fei, Guan Xiangyu, Yu Lisha, Wang Yang, School of Water Resources and Environment, China University of Geosciences, School of Ocean Sciences, China University of Geosciences
Pages: 1423-1428
Year: 2014 Issue:  4
Journal: Chinese Journal of Environmental Engineering
Keyword:  perchlorate; nitrate-nitrogen pollution; functional genes; bio-degradation; microbial activity;
Abstract: In order to further investigate the degradation of perchlorate( ClO-4) and nitrate-nitrogen( NO-3-N) co-contaminants in environments. pcrA and cld,NirS genes,and 16S rRNA were used to characterize perchlorate reducing bacteria activity,denitrifying bacteria and total bacteria,respectively. The mechanism of biodegradation of mixed contaminants in complex environments was quantitatively illustrated by analyzing the varied genes in different phases in the presence of perchlorate and high-concentration NO-3-N. The experimental results showed when NO-3-N was present as a co-contaminant with ClO-4,under the condition of adding sufficient external acetate acting as an electron donor,NO-3did not completely inhibit the ClO-4reduction at a NO-3-N to ClO-4ratio of 5 ∶ 1( mg / L ∶ mg / L). NO-3promoted ClO-4reduction once the NO-3was completely removed. The correlations between pcrA and ClO-4concentration,and cld and ClO-4concentration were not very significant when NO-3-N was existent in the mixed system,demonstrating the limitations of using the functional genes as a marker to characterize specific microbial communities in the multi-contamination systems.