Taxonomic and Functional Differences between Microbial Communities in Qinghai Lake and Its Input Streams

Area of Science:

• Aquatic microbiology
• Ecosystem ecology
• Biogeochemical cycling

Background:

• Understanding aquatic microbial communities is key to deciphering biogeochemical cycling.
• Lakes and their input streams are interconnected, but microbial differences remain unclear.

Purpose of the Study:

• To investigate taxonomic and functional differences between microbial communities in lake water and stream biofilms.
• To explore stream-lake linkages in the Qinghai Lake watershed.

Main Methods:

• High-throughput 16S rRNA gene sequencing for bacterial community determination.
• PICRUSt for predicting functional profiles.
• Field sampling in the Qinghai Lake watershed.

Main Results:

• Distinct microbial communities were found in stream biofilms and lake water, differing taxonomically and functionally.
• Stream biofilms exhibited higher microbial network connectivity and modularity.
• Functional and taxonomic beta diversity were strongly correlated.

Conclusions:

• Microbial assemblages in streams and lakes possess unique functional and taxonomic characteristics.
• Stream biofilms are enriched in xenobiotic biodegradation, lipid metabolism, carbohydrate metabolism, oxidative phosphorylation, and nitrogen metabolism.
• Lake microbial communities show greater predicted metabolic potential in amino acid metabolism, carbon fixation, and photosynthesis.