次氯酸钠消毒剂对水体沉积物细菌群落的影响

Effect of Sodium Hypochlorite Disinfectant on Bacterial Community of Aquatic Sediment

次氯酸钠等含氯消毒剂,因具有广谱和持久杀菌能力,被广泛用于公共空间的病毒消杀,尤其是在当前新冠疫情全球流行的趋势之下。而部分次氯酸钠消毒剂流入自然水体后,可能通过改变水体微生物群落结构继而影响整个水生态系统。为分析残余的含氯消毒剂对水体沉积物微生物群落的影响,本研究通过采集水体沉积物样品,加入含氯消毒剂进行模拟实验。运用PCR扩增和高通量测序技术,对沉积物中细菌群落结构与多样性开展分析。结果表明,添加梯度浓度消毒剂后,水中余氯值会迅速下降至与对照组相近并保持平稳。细菌群落多样性随着消毒剂投加次数的增多而受到一定的抑制。同时消毒剂的投加对细菌群落结构产生显著影响,缺氧条件下生长能力较强的红环菌科(Rhodocyclaceae)成为实验中后期的优势种群。研究表明,消毒剂对细菌群落的干扰能导致群落的多样性和丰富度减小并影响群落结构,发生优势菌群的更替。虽然消毒剂在中短期内不会使水体余氯浓度显著增加,但会改变沉积物中细菌群落结构,长期可能会对河流生态系统平衡造成危害。

Chlorine-containing disinfectants like sodium hypochlorite have been widely used to eliminate viruses in public space due to their broad spectrum and long-lasting sterilizing effect,especially in the current global pandemic of COVID-19.However,sodium hypochlorite disinfectants may affect the aquatic ecosystem by changing the microbial community structure.In order to analyze the influence of residual chlorine-containing disinfectants on the microbial community of aquatic sediments,this study collected sediment samples and mixed them with chlorine-containing disinfectants to set up a simulation experiment.The bacterial community structure and diversity in the sediments were analyzed by PCR amplification and high-throughput sequencing.The results show that the residual chlorine in water decreases rapidly to the control group and remains stable,when gradient concentration disinfectant is added.The diversity of bacterial community is inhibited with the addition of disinfectant.At the same time,the addition of disinfectant has a significant effect on the bacterial community structure,and Rhodocyclaceae,which has strong growth ability under hypoxia condition,becomes the dominant bacterial family in the middle and late period of the experiment.The study indicates the disturbance of disinfectants reduces the diversity and richness and affects the structure of the bacterial community,resulting in the shift of the dominant population.Although the disinfectant does not significantly increase the residual chlorine concentration of water in the short and medium term,it may change the bacterial community structure in the sediment and may cause harm to the balance of river ecosystem in the long term.