| 引用本文: | 康入蕴,安世林,黄秀琳,吴凤亭,李学艳,杜瑛珣.光化学转化对藻源溶解性有机质微生物转化的影响机制.湖泊科学,2025,37(4):1198-1210. DOI:10.18307/2025.0412 |
| Kang Ruyun,An Shilin,Huang Xiulin,Wu Fengting,Li Xueyan,Du Yingxun.Effect mechanism of photochemical transformation on microbial transformation of algal dissolved organic matter. J. Lake Sci.2025,37(4):1198-1210. DOI:10.18307/2025.0412 |
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| 摘要: |
| 在气候变暖和人类活动增加的双重压力下，湖泊富营养化和藻类水华暴发导致大量藻源溶解性有机物（algal dissolved organic matter，ADOM）产生，其转化过程是湖泊碳循环研究的重点。为探究湖泊中光化学转化对ADOM微生物转化的影响，本研究以富营养化湖泊——太湖中的ADOM为研究对象，进行18 d的微生物培养以及先自然光照后微生物培养实验。通过紫外-可见光谱法、三维荧光光谱-平行因子分析法、傅里叶变换-离子回旋共振质谱法比较两处理组中ADOM的有色DOM、荧光DOM和分子转化差异，并通过16S rRNA测序技术探究微生物群落变化。结果表明，光照-微生物处理组溶解性有机碳的降解速率明显低于微生物处理组（0.28 d-1 vs. 0.75 d-1 ）。转化过程中荧光组分和分子的变化显示：光化学过程对类蛋白质/多肽类分子的转化减少了微生物转化的底物，且光化学生成的分子仅有近一半能够被后续的微生物过程利用。微生物处理组细菌多样性显著高于光照-微生物处理组；一些菌属的丰度与DOM组分显著相关，表明光化学过程对ADOM组成的改变是影响微生物群落结构的重要原因。研究揭示了自然光照对ADOM微生物转化的抑制机制，有助于全面理解富营养化湖泊的碳循环过程。 |
| 关键词: 藻源溶解性有机质 光化学 微生物转化 分子组成 细菌群落结构 太湖 |
| DOI：10.18307/2025.0412 |
| 分类号: |
| 文献标识码:A |
| 基金项目:国家自然科学基金项目（42271117, 42471137）、江苏省创新支撑计划（软科学研究）专项（BK20231516）和中国科学院南京地理与湖泊研究所“十四五”揭榜挂帅项目（NIGLAS2022GS09）联合资助 |
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| Effect mechanism of photochemical transformation on microbial transformation of algal dissolved organic matter |
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Kang Ruyun1，2，An Shilin2，3，4，Huang Xiulin2，Wu Fengting1，2，Li Xueyan1，Du Yingxun2，3，4
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1:School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009 , P.R.China,2:State Key Laboratory of Lake and Watershed Science for Water Security, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 211135 , P.R.China,3:University of Chinese Academy of Sciences, Nanjing, Nanjing 211135 , P.R.China,4:University of Chinese Academy of Sciences, Beijing 100049 , P.R.China
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| Abstract: |
| Under the dual pressures of climate warming and anthropogenic activities, lake eutrophication and algal blooms have expanded in the world, releasing large amounts of algal dissolved organic matter (ADOM). Its transformation is highly concerned in the field of lake carbon cycling. To reveal the role of photochemical transformation on the microbial transformation of ADOM in lakes, we compared the ADOM transformation in microbial treatment and natural light-microbial treatment. The differences in the transformation of ADOM in these two treatments were compared in detail through ultraviolet-visible spectroscopy, three-dimensional fluorescence spectroscopy-parallel factor analysis, and Fourier transform-ion cyclotron resonance mass spectrometry. In addition, microbial community was explored by 16S rRNA sequencing. The results showed that the solar irradiation greatly inhibited the dissolved organic carbon removal rate by microbial treatment (0.28 d-1 vs. 0.75 d-1 ). Changes in the fluorescent components and molecular composition demonstrated that photochemical and microbial processes compete significantly for peptide-like components and peptide-like compounds. In addition, only part (about 50%) of the photochemically generated molecules could be utilized by subsequent microbial processes. The bacterial diversity in microbial treatment was significantly higher than that of the light-microbial treatment. The significant correlation between the abundance of some bacteria taxa and DOM components suggested that the alteration of ADOM composition by photochemical transformation had a key influence on the structure of the microbial community. Our study revealed the inhibitory mechanism of natural light on the microbial transformation of ADOM, which is important to understand the carbon cycling within eutrophic lakes. |
| Key words: Algal dissolved organic matter photochemistry microbial transformation molecular composition bacterial community Lake Taihu |
