微观水力条件下给水管网微生物聚集行为解析及数值模拟

Diverse microbial aggregates regulate microbial stability in water distribution networks, directly affecting safety of drinking water. Formation of microbial aggregation results from complex interactions between microbes and their micro-habitats. Micro-hydraulic conditions are critical factors shaping nutrient, disinfectant and suspended particulate fields along with microbial behaviors, and are thus key to understanding of the interactions between microbes and their micro-habitats; however, knowledge about microbial dynamics and their interplay with in situ micro-habitat is very limited. The primary goal of this project is to explore the response patterns of microbes to complex and dynamic micro-habitat and their interaction through the combination of experimental analysis and numerical simulation; and to reveal microbial motility, growth, attachment, production of extracellular polymeric substances, microbial diversity and aggregation considering micro-hydraulic conditions in water distribution networks. The proposed research would provide mechanistic understanding of microbial dynamics by linking microbial activity with micro-scale hydro-biophysical process in water distribution networks, and may lead to new insights into microbial protocols. The capability of a computational tool for quantitative analysis of microbial growth, dispersion, attachment, aggregation, and interactions with hydro-physical process would be of great utility for predicting microbial growth dynamics in water distribution networks, and thus provides a scientific basis and theoretical support for stable operation and security decision making of water distribution networks susceptible to microbial contamination.

微生物聚集模式决定了给水管网的微生物稳定性，直接影响饮用水水质安全。给水管网中微生物聚集的形成是微生物与其微生境复杂交互作用的结果。微观水力条件是影响营养物、消毒剂、悬浮颗粒物分布以及微生物行为的决定因素，是剖析给水管网中微生物聚集行为的关键，但迄今为止对微生物行为和这种交互影响的认知还十分匮乏。项目从微观水力条件出发，采用实验研究、机理分析和数值模拟相结合的方法，研究给水管网中不同运行条件下微生物附着和聚集过程，探讨微观水力条件下微生物运动、生长和附着、微生物种群以及聚集行为的影响机制，定量描述微尺度下水流特征、物质扩散反应过程以及微生物的行为过程，构建微观水力条件与微生物附着和聚集体形成的定量关系，揭示微生物附着和聚集行为的形成机制，为给水管网微生物污染控制提供理论指导和新的思路，并为其稳定运行和水质安全决策提供科学依据和理论基础，以提高供水安全性。

给水管网是一个复杂的、动态变化的生态系统，微生物会以自聚集的方式来应对其环境条件并形成生物膜。微生物聚集模式决定了给水管网的微生物稳定性，直接影响饮用水水质安全。微观水力条件是影响营养物、消毒剂、悬浮颗粒物分布以及微生物行为的决定因素，是剖析给水管网中微生物聚集行为的关键，但迄今为止对微生物行为和这种交互影响的认知还十分匮乏。首先，我们采用实验研究、机理分析和数值模拟相结合的方法，研究了静止条件下，水中余氯、营养条件、悬浮颗粒物对微生物聚集和生物膜形成的影响机制，揭示了细菌运动和胞外聚合物分泌在其中的调控作用；在此基础上，进而解析不同流速条件下细菌胞外聚合物的分泌、种群分布以及初期附着和聚集机制，探讨微观水力条件下微生物运动、生长和附着、微生物种群以及聚集行为的影响机制。该项研究阐释了环境压力胁迫下给水管网微生物附着和聚集行为的形成机制，可为给水管网微生物污染控制提供理论指导和新的思路，并为其稳定运行和水质安全决策提供科学依据和理论基础，以提高供水安全性。