Soil and bromeliads are important habitats contributing to the biodiversity of the Atlantic Forest in Brazil. However, knowledge of unicellular eukaryotes and bacteria in these environments remains limited. This study compared the diversity and community structure of unicellular eukaryotes, fungi, metazoan, and bacteria in bromeliad water tanks (BWT) and adjacent soil using 16S and 18S rRNA gene metabarcoding. Communities differed significantly between habitats but shared some taxa, suggesting habitat connectivity. Ciliates dominated unicellular eukaryotes in BWT, while Cercozoa prevailed in soil. Bacterial communities were dominated by Pseudomonadota, while fungal composition was more uniform, with Ascomycota as the dominant phylum across samples. Metazoan communities varied among abundant phyla, and their presence in BWT suggests the use of this water resource within the forest. This study provides essential baseline data on eukaryotic and bacterial diversity in this unique ecosystem, highlighting how distinct habitats within the Atlantic Forest support different communities.

Keywords: Ciliophora; Rhizaria; biodiversity; eDNA; fungi; metazoans; microbial communities; phytotelmata; protists.

© 2025 International Society of Protistologists.

巴西的大西洋森林中的土壤和凤梨科植物对生物多样性做出了重要贡献。然而，关于这些环境中单细胞真核生物和细菌的知识仍然有限。本研究通过使用16S和18S rRNA基因宏条形码技术，比较了凤梨科植物水罐（BWT）及其相邻土壤中单细胞真核生物、真菌、后生动物和细菌的多样性和群落结构。不同栖息地之间的社区存在显著差异，但共享某些物种，这表明栖息地之间可能存在连接性。纤毛虫在BWT中的单细胞真核生物中占主导地位，而肉足虫则在土壤中占据优势。细菌群落主要由拟杆菌门（Pseudomonadota）组成，而真菌的组成更加均匀，其中子囊菌门（Ascomycota）是所有样本中最常见的门类。后生动物群落在丰富的门类之间变化多样，它们出现在BWT中表明这些水体资源在森林中的使用情况。本研究提供了关于这种独特生态系统中真核生物和细菌多样性的重要基础数据，强调了大西洋森林内不同栖息地支持着不同的社区。

关键词：纤毛虫；肉足动物；生物多样性；环境DNA；真菌；后生动物；微生物群落；植物水体；原生动物。

© 2025 国际原生动物学会。