Research
| Title： | Biodiversity and Community Assembly of Endorheic Rivers on Earth's Largest Plateau |
|---|---|
| First author： | Feng, Xiu; Chen, Kai; Zhu, Ren; Jia, Yintao; Sui, Xiaoyun; Xiong, Xiong; Zhu, Huan; Li, Bing; Sun, Huanhuan; Mu, Tong; Jiang, Chuanqi; Miao, Wei; Chen, Yifeng |
| Journal： | FRESHWATER BIOLOGY |
| Years： | 2025 |
| DOI： | 10.1111/fwb.70087 |
| Abstract： | Understanding biodiversity distribution patterns and related environmental factors and community assembly mechanisms is crucial for deciphering community responses and feedback to global changes, but it remains largely unknown in aquatic ecosystems on the Qinghai-Tibet Plateau (QTP) which is the Asian water tower and one of the regions most severely affected by climate changes. Here, by analysing environmental DNA metagenomic and metabarcoding sequencing data of water samples from the ice margin to the lake along two endorheic rivers (Tsachu Tsangpo and Bochu Tsangpo) on the QTP, we examined the alpha and beta diversity and the ecological processes driving community assembly of various taxonomic groups (bacteria, fungi, eukaryotic algae, protozoa, metazoan invertebrates and vertebrates). We found no significant continuous change in alpha diversity from the ice margin to lake along the two rivers for most taxonomic groups, except for fungi in Tsachu Tsangpo, which showed a gradual decline. Alpha diversity was significantly correlated with various environmental factor, including total nitrogen and ammonium nitrogen for bacteria, turbidity for fungi, total phosphorus and nitrate nitrogen for eukaryotic algae, chloride ion for protozoa and total phosphorus for metazoan invertebrates. Community compositions of these taxonomic groups were significantly correlated to similar environmental factors, such as water temperature, turbidity, nitrate nitrogen, and total organic carbon. Furthermore, homogeneous selection, dispersal limitation and drift mainly contributed to the community assembly in both rivers, with a higher importance of deterministic processes and lower importance of stochastic processes for bacteria, eukaryotic algae and protozoa than for metazoan invertebrates and fungi. The results demonstrated various environmental factors correlated with the alpha and beta diversity of multi-taxonomic groups in the two endorheic rivers. Deterministic processes were more prominent in the community assembly of bacteria, eukaryotic algae and protozoa than in metazoan invertebrates and fungi. These findings would help to understand how aquatic organisms on the QTP respond to climate change. |
