Ni Ren-Xiang, Zhang Bo, Gao Han, Zhang Jing-Jing, Wang Rong, Chen Juan
College of Environment, Hohai University, Nanjing 210098, China.
Key Laboratory of Integrated Regulation and Resource Department on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, China.
Huan Jing Ke Xue. 2025 Jun 8;46(6):3406-3414. doi: 10.13227/j.hjkx.202405205.
Planktonic bacteria play a vital role in the material cycling and energy flow of river ecosystems. However， little is known about the diversity and co-existence network relationship of riverine planktonic bacteria under multiple stressors. This study investigated the impact of nutrients， heavy metals， and antibiotics on the planktonic bacterial diversity and co-existence relationship in Raohe River， the classic river entering Poyang Lake， as well as its two tributaries， Changjiang and Le'an Rivers. The results showed that planktonic bacterial community structure varied significantly among the three river sections， and the alpha diversity of planktonic bacteria in Le'an River was significantly lower than that in Changjiang and the lake entry segment. The dominant planktonic bacterial phyla were Proteobacteria， Bacteroidetes， and Actinobacteria in Raohe River. The co-occurrence network analysis revealed that the network complexity and relative abundance of key species of planktonic bacteria in the lake entry segment were higher than those in Changjiang and Le'an River， indicating that the co-existence relationship of planktonic bacteria were stronger in the lake entry segment. A variance partitioning analysis indicated that nutrients and heavy metals were the main driving factors for the diversity and co-existence relationship of planktonic bacteria. The research results contribute to understanding the characteristics of riverine planktonic bacteria influenced by multiple stressors and provide a scientific basis for predicting and managing the ecological health of the river.
浮游细菌在河流生态系统的物质循环和能量流动中发挥着至关重要的作用。然而，对于多重压力源下河流浮游细菌的多样性和共存网络关系，人们了解甚少。本研究调查了营养物质、重金属和抗生素对饶河（流入鄱阳湖的典型河流）及其两条支流长江和乐安河的浮游细菌多样性和共存关系的影响。结果表明，三个河段的浮游细菌群落结构存在显著差异，乐安河浮游细菌的α多样性显著低于长江和入湖段。饶河浮游细菌的优势门类为变形菌门、拟杆菌门和放线菌门。共现网络分析表明，入湖段浮游细菌的网络复杂性和关键物种的相对丰度高于长江和乐安河，这表明入湖段浮游细菌的共存关系更强。方差分解分析表明，营养物质和重金属是浮游细菌多样性和共存关系的主要驱动因素。研究结果有助于了解受多重压力源影响的河流浮游细菌的特征，并为预测和管理河流的生态健康提供科学依据。
