Greenhouse Gases in Wuhan Lakes
To explore the transformation mechanism of dissolved organic matter (DOM) and carbon dioxide (CO2), as well as its carbon sequestration principle within the algal-bacterial symbiotic system, a three-month microscopic algal culture experiment was conducted. By combining FT-ICR MS with metagenomics, the carbon cycling process, along with transformation of DOM molecules and the emission and fixation of CO2 during the whole growth and decline phase were analyzed. Algal respiration and DOM degradation were the principal pathways for CO2 production. Specifically, carbohydrates, proteins and lipids, which were easily degraded, contributed significantly to CO2 production. Additionally, a small quantity of CO2 was generated through the degradation of certain degradation-resistant DOM molecules like lignin and unsaturated hydrocarbons. The easily decomposable DOM molecules were gradually converted into difficult-to-degrade molecules via the algal-bacterial symbiotic system.