Wu Hainan, Zhou Jiahui, Zhang Sen, Gao Yu, Wang Chengkai, Cong Haibing, Feng Shaoyuan
College of Environmental Science and Engineering, Yangzhou University, Yangzhou, 225009, PR China.
Key Lab of Basin Water Resource and Eco-Environmental Science in Hubei Province, Basin Water Environmental Research Department, Changjiang River Scientific Research Institute, Wuhan, 430010, PR China; Innovation Team for Basin Water Environmental Protection and Governance of Changjiang Water Resources Commission, Wuhan, 430010, PR China.
J Environ Manage. 2024 Nov;370:122559. doi: 10.1016/j.jenvman.2024.122559. Epub 2024 Sep 27.
Aerobic composting is a useful method for managing and disposing of salvaged algal sludge. To optimize the composting process and improve compost quality, it is necessary to understand the functions and responses of microbial communities therein. This work studied the degradation process of organic matter and the assemblage of bacterial communities in algal sludge composting via 16S rRNA amplicon sequencing. The results showed that 77.08% of the microcystin was degraded during the thermophilic stage of composting, which was the main period for microcystin degradation. Bacterial community composition and diversity changed significantly during the composting, and gradually stabilized as the compost matured. Different composting stages may be dominated by different module groups separately, as shown in the co-occurrence networks of composting bacterial communities. In the networks, all bacteria associated with microcystin degradation were identified as connectors between different module groups. The algal sludge composting process was driven primarily by deterministic processes, and the main driving forces for bacterial community assembly were temperature, dissolved organic carbon, ammonium, and microcystin. At last, by applying the structural equation modeling method, the bacterial communities under influences of physiochemical properties were proved as the main mediators for the microcystin degradation. This study provides valuable insights into the optimization of bacterial communities in composting to improve the efficiency of microcystin degradation and the quality of the compost product.
好氧堆肥是处理打捞上来的藻类污泥的一种有效方法。为了优化堆肥过程并提高堆肥质量，有必要了解其中微生物群落的功能和反应。这项工作通过16S rRNA扩增子测序研究了藻类污泥堆肥过程中有机物的降解过程和细菌群落的组装。结果表明，在堆肥的嗜热阶段，77.08%的微囊藻毒素被降解，这是微囊藻毒素降解的主要时期。堆肥过程中细菌群落组成和多样性发生了显著变化，并随着堆肥成熟而逐渐稳定。不同的堆肥阶段可能分别由不同的模块组主导，如堆肥细菌群落的共现网络所示。在这些网络中，所有与微囊藻毒素降解相关的细菌都被确定为不同模块组之间的连接点。藻类污泥堆肥过程主要由确定性过程驱动，细菌群落组装的主要驱动力是温度、溶解有机碳、铵和微囊藻毒素。最后，通过应用结构方程建模方法，证明了受理化性质影响的细菌群落是微囊藻毒素降解的主要介导者。本研究为优化堆肥中的细菌群落以提高微囊藻毒素降解效率和堆肥产品质量提供了有价值的见解。
