High-frequency monitoring reveals a CO₂ source-sink shift in a subtropical eutrophic urban lake.

ABSTRACT: Eutrophic urban lakes with CO₂-supersaturation represent potential carbon (C) sources; however, the drivers behind the reported C-source-sink shift remain poorly understood. This study provides a systematic assessment of daytime/seasonal pCO₂ and fCO₂ dynamics in a subtropical moderately eutrophic urban lake (Bailuwan, China), based on over a year of high-frequency monitoring, aiming to clarify the mechanisms regulating CO₂ exchange at the water-air interface in such ecosystems. Our work revealed consistent daytime declines in pCO₂ (and fCO₂) on 12 sampling days, though morning-afternoon differences were not significant (n = 24). Novel episodic undersaturation events were newly observed in October 2020 and March 2021, contra

SUBMITTER: Liu S 

PROVIDER: S-EPMC12680723 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature