持续自然混合期水体微生物特性变化及对水质改善影响研究
- Microbiological changes in water bodies during continuous natural mixing and the impact on water quality improvement
- 基金项目：国家重点研发计划课题（2022YFC3203604）；陕西省重点研发计划项目（2022ZDLSF06-08）；陕西省重点科技创新团队项目（2023-CX-TD-32）
- 摘要：近年来,大中型水库逐渐成为城市主要的饮用水来源,其水质安全逐渐成为全球关注的问题。原位实验证明,扬水曝气系统可以破坏水库水体分层,人为诱导水体提前进入自然混合时期,比未经人为干预的水体提前了2.5个月。然而,对于持续自然混合期的水体生物特性(碳代谢活性、群落结构及多样性)变化与水质改善之间的关系仍缺乏深入研究。为此,本文系统研究了持续自然混合期李家河水库水质参数、污染物浓度、细菌碳代谢活性、物种组成和微生物群落共生模式的时空变化。持续自然混合初期水体菌群具有较高的丰度及碳代谢活性,随着持续混合的进行,均呈现逐渐下降的趋势。整个持续自然混合期水体细菌群落结构以放线菌门和变形菌门为主,优势属为CL500-29_marine_group(26.65%)和hgcI_clade(18.21%)。共生网络分析表明持续自然混合初期细菌群落间相互作用更复杂紧密。冗余分析则表明微生物种群结构受环境因子和水质因子的共同调控。相关性分析表明功能微生物与水质间具有显著相关性,对水质改善起到积极作用。总体而言,该研究结果将为饮用水水源水质改善原位生物修复提供科学依据。
- Abstract：In recent years, large and medium-sized reservoirs have gradually become the main source of drinking water for cities, and their water quality safety has gradually become a global concern. In situ experiments have demonstrated that the lift aeration system can disrupt the stratification of reservoir water bodies and artificially induce water bodies to enter the natural mixing period 2.5 months earlier than those without human intervention. However, there is still a lack of in-depth research on the relationship between changes in biological characteristics (carbon metabolism activity, community structure and diversity) and water quality improvement in water bodies during the sustained natural mixing period. To this end, this paper systematically investigated the spatial and temporal changes in water quality parameters, pollutant concentrations, bacterial carbon metabolic activity, species composition and microbial community symbiosis patterns in Lijiahe Reservoir during the sustained natural mixing period. At the beginning of the sustained natural mixing period, the water column bacterial community had high abundance and carbon metabolism activity, and both of them showed a decreasing trend as the sustained mixing progressed. The bacterial community structure in the water body during the whole period of continuous natural mixing was dominated by Actinobacteria and Ascomycetes, and the dominant genera were CL500-29_marine_group (26.65%) and hgcI_clade (18.21%). Symbiotic network analyses indicated more complex and tight interactions among bacterial communities in the early stages of sustained natural mixing. Redundancy analyses, on the other hand, indicated that microbial population structure was co-regulated by environmental and water quality factors. Correlation analysis showed that the functional microorganisms were significantly correlated with water quality and played a positive role in water quality improvement. Overall, the results of this study will provide a scientific basis for in situ bioremediation of drinking water sources to improve water quality.
