Abstract：
Source separation and decentralized domestic wastewater treatment represent effective strategies to enhance sewage treatment performance and facilitate water reuse economically. The Living Machine (LM) system has gained widespread adoption for decentralized sewage treatment. While underwater light source has been demonstrated to enhance the treatment performance of open aerobic reactors in LM systems, its influence on the treatment efficiency of a fully multistage LM system remains underreported. In this study, an underwater lamp-added LM system (ULLM) with eight reactors was constructed and investigated. The introduction of underwater light source obviously improved the removal capacity of chemical oxygen demand (COD) and NH4+-N, which was 96.1% and 61.6%, respectively. The diversity of algae, zooplankton, and aquatic animals was notably higher in the light-treated reactors than in the control group (CK) without underwater light source, and substantial alteration in the microbial community of the light-treated reactors was observed compared with CK reactors. At the phylum level, Proteobacteria and Nitrospirae enriched in the underwater light-treated reactors, while Bacteroidetes and Actinobacteria exhibited a decrease after light exposure. At the genus level, Nitrospira and Rhodanobacter were enriched in the ULLM system. Importantly, the prevalence of these two dominant genera was sustained until the final operational stage, indicating their potential key roles in enhancing wastewater treatment performance. The addition of underwater light source proves to be an effective strategy for augmenting the treatment efficiency of the multistage living machine systems, resulting in substantial improvements in pollutant removal. These findings contribute valuable insights into optimizing LM systems for decentralized wastewater treatment.
摘要：
源分离和分散式生活污水处理是提高污水处理性能和经济促进水回用的有效策略。LivingMachine（LM）系统已广泛用于分散式污水处理。虽然已证明水下光源可增强LM系统中开放式好氧反应器的处理性能，它对完全多级LM系统的处理效率的影响仍未得到充分报道。在这项研究中,构建并研究了具有八个反应器的水下加灯LM系统（ULLM）。水下光源的引入明显提高了化学需氧量(COD)和NH4+-N的去除能力,分别为96.1%和61.6%，分别。藻类的多样性，浮游动物,和水生动物在光处理的反应器中明显高于没有水下光源的对照组（CK），与CK反应器相比，观察到光处理反应器的微生物群落发生了实质性变化。在门一级，在水下光处理的反应器中富集的变形杆菌和Nitrosirae，而受光后，拟杆菌和放线菌表现出减少。在属一级，在ULLM系统中富集了硝基螺旋体和红杆菌属。重要的是,这两个优势属的流行一直持续到最后的操作阶段，表明它们在提高废水处理性能方面的潜在关键作用。水下光源的添加被证明是提高多级生活机器系统的治疗效率的有效策略，导致污染物去除的实质性改进。这些发现为优化LM系统以进行分散式废水处理提供了宝贵的见解。
