The variability of lake partial carbon dioxide pressure ( p CO 2 ) introduces uncertainty into CO 2 flux estimates. Knowing the variation pattern of p CO 2 is important for obtaining an accurate global estimation.
In a recent article published in Environmental Science and Ecotechnology , researchers examined seasonal and trophic variations in lake p CO 2 based on 13 field campaigns conducted in Chinese lakes from 2017 to 2021. They found significant seasonal fluctuations in p CO 2 , with decreasing values as trophic states intensify within the same region.
These p CO 2 dynamics resulted in variable CO 2 emissions, with lakes exhibiting different trophic states, and saline lakes differing from freshwater lakes (−23.1 ± 17.4 vs. 19.3 ± 18.3 mmol m −2 d −1 ). These spatiotemporal p CO 2 variations complicate total CO 2 emission estimations.
Using area proportions of lakes with varying trophic states and salinity in China, the researchers estimate China's lake CO 2 flux at 8.07 Tg C yr −1 . In future studies, the importance of accounting for lake salinity, seasonal dynamics, and trophic states must be used to enhance the accuracy of large-scale carbon emission estimates from lake ecosystems in the context of climate change.
The study indicated that the current annual total CO 2 fluxes from lakes in China might be overestimated when lake trophic states and salinity are ignored.
To improve the accuracy of regional and large-scale estimations of carbon emissions and carbon budgets in lake ecosystems affected by seasons, salinity, and trophic states, further investigations into CO 2 emissions from lakes in other parts of the world are warranted.
Journal
Environmental Science and Ecotechnology
DOI
https://doi.org/10.1016/j.ese.2023.100337
Article Title
Re-estimating China's lake CO 2 flux considering spatiotemporal variability
Article Publication Date
25 November 2023
Observational study
Not applicable
Re-estimating China's lake CO2 flux considering spatiotemporal variability
25-Nov-2023