Hydrological and biogeochemical controls on temporal variations of dissolved carbon and solutes in a karst river, South China

Riverine carbon cycling in karst regions exhibits high sensitivity to climate change, with hydrological and biogeochemical processes playing pivotal roles. A study on the Guijiang River, South China, revealed that high discharges during warm-wet seasons accelerate solute transport and organic carbon mineralization, leading to significant CO2 consumption (760.4 × 10³ mol/km²/year), far exceeding global averages. Stable carbon isotope analysis of dissolved inorganic carbon (δ¹³C_DIC) showed that biological carbon contributes up to 53% of DIC, influencing temporal carbon dynamics. The research highlights the critical impact of climate variability on chemical weathering and carbon fluxes in karst areas, emphasizing the need for further investigation into these processes under changing climatic conditions.

Liu, J., Zhong, J., Chen, S., Xu, S., & Li, S.-L. (2021). Hydrological and biogeochemical controls on temporal variations of dissolved carbon and solutes in a karst river, South China. Environmental Sciences Europe, 33(1). https://doi.org/10.1186/s12302-021-00495-x