Carbon sequestration by alga ecosystems

• Algal bio-eco-technological function displayed via natural water medium.
• Excellent algal CO2 biofixation demonstrated with mimicked ecosystem.
• Microalgae have high potential for removing nitrogen and phosphorus from natural water medium.
• This study established the algae function in ecosystem for CO2 biofixation.

Algae play an essential role on global carbon cycle and have great potential for CO2 biofixation. The study was to investigate the carbon use potential of microalgae under imitated fresh water ecosystem. Biofixation of CO2 by microalgae mass culture represents an advanced, physicochemical, biological and ecological process that enables direct utilization of CO2 from the atmosphere. This study demonstrated that over 100% carbon source from the air was consumed. The relevant environmental variables were monitored and analyzed, furthermore mathematically selected crucial factors of the unsupplemented freshwater medium growth and finally explained the complexity of the algal nature to provide better insights of the niche in the ecosystem. Consequently, the statistical/mathematical analyses of CO2 uptake rates demonstrated laboratory uptaking atmospheric CO2 as the major carbon source in the algal growth system.