The interplay between the terrestrial carbon cycle and emissions of carbon dioxide from streams and rivers into the atmosphere is at the center of a new Yale School of the Environment-led study. The study aimed at calculating the amount for the global carbon emissions budget.
The study by a team of researchers was published in PNAS. The study compiled 5,910 direct measurements of fluvial CO2. Globally. The magnitude of stream and river CO2 emissions is affected by seasonal changes, watershed biogeochemistry and hydrology. Global estimates of the flux were uncertain.
The study builds on research which developed the first global map of the surface area of water bodies and their carbon emissions. There were no on-site direct measurements, when the study was published. The calculations were based on alkalinity and pH and other data.
The study found that monthly emissions fluxes vary more in the Arctic and northern temperate rivers than in tropical and southern temperate rivers.
The findings highlight the importance of hydrology in water’s role in routing terrestrial carbon to the atmosphere via global drainage networks.
The amount of terrestrial CO2 that gets stripped into streams and rivers and then emitted into the atmosphere is modulated by river discharge. Climate change and human impact will also play a role in the terrestrial carbon cycle and emissions from streams and rivers as some areas become dryer and other areas become wetter.