Department of Microbiology, ELTE Eötvös Loránd University, Pázmány P. sétány 1/C, Budapest, 1117, Hungary.
Institute of Aquatic Ecology, HUN-REN Centre for Ecological Research, Karolina út 29, Budapest, 1113, Hungary.
Sci Rep. 2024 Oct 12;14(1):23881. doi: 10.1038/s41598-024-75863-7.
Freshwaters play an essential role in providing ecosystem services worldwide, however, the water quality of different water bodies is strongly influenced by human activities such as urbanization, industry and agriculture. In this study, water and biofilm samples were collected from the main channel of the Danube River upstream and downstream of a metropolitan, from a regulated side arm within an urbanized area, and from two differently separated oxbow lakes located in nature conservation areas. The taxonomic diversity of bacterial communities was revealed by 16S rRNA gene-based amplicon sequencing using Illumina MiSeq platform. The results showed that all samples were dominated by phyla Pseudomonadota, Actinobacteriota and Bacteroidota. The bacterial community structures, however, clearly differentiated according to planktonic and epilithic or epiphytic habitats, as well as by riverine body types (main channel, side arm, oxbow lakes). The taxonomic diversity of biofilm communities was higher than that of planktonic ones in all studied habitats. Human impacts were mainly reflected in the slowly changing biofilm composition compared to the planktonic ones. Genera with pollution tolerance and/or degradation potential, such as Acinetobacter, Pseudomonas and Shewanella were mainly detected in biofilm communities of the highly urbanized section of the river side arm.
淡水在提供全球生态系统服务方面发挥着至关重要的作用，但不同水体的水质受到人类活动的强烈影响，如城市化、工业和农业。在这项研究中，从都市化地区的多瑙河干流上下游、一个受管制的支流以及两个位于自然保护区的不同分隔牛轭湖中采集了水样和生物膜样本。使用 Illumina MiSeq 平台基于 16S rRNA 基因扩增子测序揭示了细菌群落的分类多样性。结果表明，所有样本均以假单胞菌门、放线菌门和拟杆菌门为主。然而，根据浮游生物和附生或附生栖息地以及河流类型（干流、支流、牛轭湖），细菌群落结构明显分化。在所有研究的栖息地中，生物膜群落的分类多样性均高于浮游生物群落。人类活动的影响主要反映在与浮游生物相比，生物膜组成变化缓慢。在河流支流高度城市化部分的生物膜群落中，主要检测到具有耐污性和/或降解潜力的属，如不动杆菌属、假单胞菌属和希瓦氏菌属。
