how does carbon move from the atmosphere to the biosphere
Carbon moves from the atmosphere to the biosphere through a process called carbon fixation. This process involves two main pathways: photosynthesis, which occurs in plants and some microorganisms, and absorption through the oceans.
1. Photosynthesis: In this process, plants use energy from sunlight, along with water and carbon dioxide (CO2) from the atmosphere, to convert them into glucose (C6H12O6) and oxygen (O2). This glucose is then utilized by the plants as an energy source and building material. Through the food chain, carbon is transferred from plants to animals when they consume plant material.
2. Ocean Absorption: About a quarter of the carbon dioxide in the atmosphere is absorbed by the oceans. Dissolved carbon dioxide reacts with water to form carbonic acid, which dissociates into hydrogen ions (H+) and bicarbonate ions (HCO3-). These ions are then taken up by marine plants, such as algae and phytoplankton, through a process known as photosynthesis. Similarly, marine animals consume these plants, allowing carbon to move up the food chain.
Both photosynthesis and ocean absorption play vital roles in the carbon cycle, ensuring the movement of carbon from the atmosphere into the biosphere.