Chen Jing, Zhou Yongqiang, Zhang Yunlin, Guo Quanzhong, Zhang Shulan, Ge Guanghuan, Jin Wenting
College of Chemistry and Environment, Ankang University, Ankang, Shaanxi, China.
Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China.
Environ Microbiol Rep. 2025 Apr;17(2):e70094. doi: 10.1111/1758-2229.70094.
Decomposition of Cyanobacterial blooms frequently occurs in Lake Taihu, releasing various fractions of algal organic matter into the water through cell lysis. These fractions influence the production and consumption of dissolved organic matter, nutrient dynamics, and bacterial succession in the lake. However, the interactions between free-living and particle-attached bacterial communities with different algal organic matter fractions remain poorly understood. Herein, we investigated the effects of two distinct algal organic matter fractions, obtained through a fractionation procedure simulating cyanobacterial bloom collapse, on freshwater bacterial communities. The degradation of both fractions resulted in stage-specific changes in the chemical properties of lake water, which were divided into two distinct stages (labeled Stage I and Stage II). Flavobacteriaceae was dominant in Stage I, whereas Methylophilaceae dominated Stage II. Long-term ecological observations indicated that particle-attached bacteria responded more sensitively to different algal organic matter fractions than free-living bacteria. Compared to the degradation of algal-derived filtrate, the breakdown of algal residual exudative organic matter led to a more complex free-living bacterial community network. These findings provide new insights into the capacity of free-living and particle-attached bacterial communities to utilize different algal organic matter fractions and highlight their roles in aquatic ecosystems during the post-bloom stage.
蓝藻水华分解现象在太湖频繁发生，通过细胞裂解将各种藻类有机物质释放到水中。这些组分影响湖泊中溶解有机物的产生与消耗、营养动态以及细菌演替。然而，自由生活细菌群落和附着在颗粒上的细菌群落与不同藻类有机物质组分之间的相互作用仍知之甚少。在此，我们研究了通过模拟蓝藻水华崩溃的分级程序获得的两种不同藻类有机物质组分对淡水细菌群落的影响。两种组分的降解导致湖水化学性质发生阶段特异性变化，分为两个不同阶段（标记为第一阶段和第二阶段）。黄杆菌科在第一阶段占主导地位，而嗜甲基菌科在第二阶段占主导地位。长期生态观测表明，附着在颗粒上的细菌对不同藻类有机物质组分的反应比自由生活细菌更敏感。与藻类衍生滤液的降解相比，藻类残留渗出有机物质的分解导致更复杂的自由生活细菌群落网络。这些发现为自由生活细菌群落和附着在颗粒上的细菌群落利用不同藻类有机物质组分的能力提供了新见解，并突出了它们在水华后阶段水生生态系统中的作用。
