1. Oceans: The oceans absorb a vast amount of CO2 from the atmosphere. This process is called ocean acidification, which can have negative impacts on marine life.
2. Soil: Soil microorganisms, such as bacteria and fungi, decompose organic matter and release CO2, but they also absorb CO2 during the process of respiration.
3. Weathering of rocks: The chemical weathering of rocks, especially carbonates like limestone, absorbs CO2 from the atmosphere.
4. Human-made sinks: Some human activities, like carbon capture and storage (CCS) technologies, are designed to remove CO2 from the atmosphere and store it underground.
5. Industrial processes: Some industrial processes, like the production of cement, release CO2, but others, like the production of biofuels, can potentially absorb CO2.
Therefore, while plants are crucial for carbon absorption, it's important to remember that the carbon cycle is complex and involves various biological, geological, and human-driven processes.