青藏高原不同盐度湖泊细菌群落多样性及DOM分布特征  

Bacterial diversity and DOM composition distribution in lakes with different salinity levels on Qinghai-Tibetan Plateau

作　　者：张佩莲 张含笑 霍守亮[1] 李怡 张靖天[1] 翁南燕 ZHANG Peilian;ZHANG Hanxiao;HUO Shouliang;LI Yi;ZHANG Jingtian;WENG Nanyan(State Key Laboratory of Environmental Criteria and Risk Assessment,Chinese Research Academy of Environment Sciences,Beijing 100012)

机构地区：[1]中国环境科学研究院环境基准与风险评估国家重点实验室,北京100012

出　　处：《环境科学学报》2024年第5期158-168,共11页Acta Scientiae Circumstantiae

基　　金：国家重点研发计划项目(No.2022YFC3201900)。

摘　　要：微生物在水生生态系统碳循环中发挥着重要的作用,目前对湖泊微生物组成与有机质之间的空间尺度联系以及对盐度的响应了解仍然有限.青藏高原对全球气候变化最为敏感的区域之一,是我国重要的生态安全屏障.本研究以青藏高原12个不同盐度的湖泊作为研究对象,运用微生物测序技术和光谱分析方法探讨了湖泊细菌群落多样性与溶解有机质(DOM)组成和来源特征,通过三维荧光光谱矩阵-平行因子分析(PARAFAC)共识别出4种不同来源的荧光组分(C1~C4),并通过相关分析、冗余分析以及共现网络分析探究了细菌与DOM组成之间的联系以及对环境因素的响应.结果表明:(1)青藏高原湖泊不同盐度组别间细菌组成存在显著性差异(p<0.05),细菌α多样性(群落丰度)和β多样性受到盐度的显著影响;(2)细菌群落组成与DOM中的类腐殖质C3和类蛋白质C4组分存在显著相关,可能与多种细菌的协同作用有关;(3)DOM组成是影响细菌群落组成的关键因素,DOM光谱参数能够解释细菌群落组成69.56%的变化.本研究表明了水体DOM组成对湖泊细菌群落的显著影响,为青藏高原湖泊微生物与DOM相互作用机制研究提供了新的见解.Aquatic microbes play a critical role in the global carbon cycle.However,the current understanding of how lake microbial community responds to organic matter and varying salinity gradients on a spatial scale is still limited.The Qinghai-Tibetan Plateau(QTP) is one of the most sensitive regions to climate change,providing an ideal area to investigate the impact of natural environment on lake microbial communities.In this study,microbial sequencing technology and spectral analysis were used to explore the diversity of bacterial communities and the composition and sources of dissolved organic matter(DOM) in 12 lakes with different salinity on the QTP.Four distinct sources of fluorescence components(C1~C4) were identified by three-dimensional fluorescence spectral matrix-parallel factor analysis(PARAFAC).The relationship between microorganisms and DOM composition,as well as their response to environmental factors,were revealed by correlation analysis,redundancy analysis,and co-occurrence network analysis.The results showed that there are statistically significant differences in composition and α-and β-diversity of bacterial communities among lakes with different salinity groups(p<0.05).The composition of bacterial communities was significantly related with the humus-like C3 and protein-like C4 fractions in DOM,which may be related to the synergistic effect of multiple bacteria.DOM composition explained 69.56% of the variation in bacterial community composition.This study highlights the significant influence of DOM composition on lake bacterial communities and provides new insights into the interaction mechanism between lake microorganisms and DOM on the QTP.

关 键 词：青藏高原湖泊 微生物多样性 盐度 溶解有机质(DOM) 平行因子分析 共现网络 

分 类 号：X524[环境科学与工程—环境工程]