All the listed subsystems of Earth are involved in the Carbon Cycle:
- Hydrosphere - Carbon is dissolved in oceans and plays a role in marine life and carbonate formation.
- Biosphere - Living organisms, including plants and animals, are key players in carbon uptake and release through processes like photosynthesis and respiration.
- Atmosphere - Carbon dioxide exists in the atmosphere and is exchanged with the Earth's surface, influencing climate and weather patterns.
- Lithosphere - Carbon is stored in rocks and soils, and geological processes can store or release carbon over long timescales.
Therefore, all four subsystems (hydrosphere, biosphere, atmosphere, and lithosphere) are involved in the Carbon Cycle.