What are the main reservoirs of carbon?

The main reservoirs of carbon are as follows:

1. The Atmosphere
2. Terrestrial Biosphere ( It includes freshwater systems and nonliving organic material)
3. Oceans (It includes inorganic carbon and living and non-living marine biota)
4. Sediments that consists mainly of fossil fuels

For more relevant articles refer to the links given below:

• UPSC Environment and Ecology Questions
• UNEP
• UPSC Environment and Ecology