Closing the inland water carbon cycle

Area of Science:

• Environmental Science
• Aquatic Chemistry
• Biogeochemistry

Background:

• Inland waters play a crucial role in the global carbon cycle.
• Understanding the drivers of carbon dioxide (CO2) emissions from inland waters is essential for accurate climate modeling.
• Previous research has focused on biological processes, but chemical factors are increasingly recognized.

Purpose of the Study:

• To investigate the multifaceted drivers of carbon dioxide (CO2) emissions from inland waters.
• To compare the contribution of ecosystem heterotrophy, chemical equilibration, and calcification to CO2 release.
• To elucidate the parallels between inland water CO2 emissions and oceanic carbon uptake.

Main Methods:

• Analysis of water chemistry parameters related to carbon cycling.
• Measurement of gas exchange rates at the water-air interface.
• Modeling of carbon fluxes incorporating biological, chemical, and physical processes.

Main Results:

• Inland water CO2 emissions were found to mirror oceanic carbon uptake patterns.
• Ecosystem heterotrophy was identified as a significant driver of CO2 emissions.
• Chemical equilibration and calcification processes were also shown to substantially influence CO2 release from inland waters.

Conclusions:

• Carbon dioxide (CO2) emissions from inland waters are influenced by a combination of biological and chemical processes.
• The findings emphasize the need to integrate chemical factors into models of aquatic carbon cycling.
• Inland waters are dynamic components of the global carbon budget, with emissions comparable to ocean carbon sinks.