PDF(Pubmed)
Abstract：
The tailwater from wastewater treatment plants serves as an important water resource in arid regions, alleviating the conflict between supply and demand. However, the effects of different tailwater discharge proportions on microbial community dynamics remain unclear. In this study, we investigated the effects of different tailwater discharge proportions on the water quality and microbial community characteristics of sediments in receiving water bodies under controlled conditions (WF-1, WF-2, WF-3, WF-4, and WF-5, containing 0% tailwater + 100% natural water, 25% tailwater + 75% natural water, 50% tailwater + 50% natural water, 75% tailwater + 25% natural water, and 100% tailwater + 0% natural water, respectively). Microbial co-occurrence networks and structural equation model were used to unveil the relationship between microbial communities and their shaping factors. Results showed that distinct microbial community compositions were found in the sediments with low- (< 50%) and high- (> 50%) proportions of tailwater. Specifically, WCHB1-41 and g_4-29-1, which are involved in organic degradation-related functions, were the key genera in the high-proportion cluster. A total of 21 taxa were more abundant in the low-proportion (< 50%) cluster than that in high-proportion (> 50%). Moreover, higher modularity was observed in the low-proportion. Total phosphorus directly affected while ammonia nitrogen indirectly affected the microbial community structure. Our findings support the distinct heterogeneity of microbial communities driven by tailwater discharge in receiving water bodies, and further confirmed that high-proportion tailwater depletes sensitive microbial communities, which may be avoided through scientific management.
摘要：
污水处理厂尾水是干旱地区重要的水资源,缓解供需矛盾。然而,不同尾水排放比例对微生物群落动态的影响尚不清楚。在这项研究中,我们研究了在受控条件下（WF-1，WF-2，WF-3，WF-4和WF-5，包含0％尾水100％天然水，不同尾水排放比例对接收水体中沉积物的水质和微生物群落特征的影响，25%尾水+75%天然水,50%尾水+50%天然水,75%尾水+25%天然水,100%尾水+0%天然水,分别)。利用微生物共生网络和结构方程模型揭示了微生物群落与其塑造因子之间的关系。结果表明，在尾水比例低（<50％）和高（>50％）的沉积物中发现了不同的微生物群落组成。具体来说,WCHB1-41和g_4-29-1参与有机降解相关功能，是高比例集群中的关键属。低比例（<50％）集群中共有21个分类单元比高比例（>50％）集群中更丰富。此外，在低比例中观察到更高的模块化。总磷直接影响微生物群落结构，氨氮间接影响微生物群落结构。我们的发现支持了由接收水体中的尾水排放驱动的微生物群落的明显异质性，并进一步证实高比例尾水消耗敏感的微生物群落，这可以通过科学管理来避免。
