Natural Carbon Fixation

Natural carbon fixation processes play a fundamental role in maintaining a balanced carbon environment on Earth. 

Photosynthesis in Plants and Algae

The process is central to carbon fixation on land and in aquatic environments. 

Plants and algae use chlorophyll to capture atmospheric carbon dioxide (CO₂) during daylight hours. CO₂ is transformed into glucose (sugar) and oxygen (O₂) through chemical reactions.

Chemolithotrophy in Certain Bacteria

Specific bacteria engage in chemolithotrophy in extreme environments like deep-sea hydrothermal vents or acidic hot springs. These bacteria use inorganic compounds, such as sulfur or iron, as energy sources to convert CO₂ into organic molecules. 

This process contributes to carbon fixation in ecosystems where traditional photosynthesis is not feasible.

The Role of Oceans and Marine Organisms

Oceans serve as crucial natural carbon sinks in the global carbon cycle. Microscopic marine plants called phytoplankton perform photosynthesis similar to land-based plants. They capture carbon dioxide from seawater and convert it into organic matter. 

Zooplankton and other marine organisms feed on phytoplankton and transfer fixed carbon through the marine food web.