Which reservoir has the largest deposit of carbon?
atmosphere
plant biomass
oceans
rocks and sediment
The atmosphere has the largest deposit of carbon.
To determine which reservoir has the largest deposit of carbon, we need to look at the carbon cycle and the storage capacity of each reservoir.
1. Atmosphere: The atmosphere contains carbon dioxide (CO2) and other greenhouse gases. While it's a significant reservoir for carbon, it has a smaller capacity compared to other reservoirs. The atmospheric carbon primarily comes from human activities such as burning fossil fuels and deforestation.
2. Plant Biomass: Plant biomass refers to the total amount of carbon stored in all living vegetation on Earth, including trees, shrubs, grasses, and other plants. Plants play a vital role in sequestering carbon through photosynthesis. However, while plant biomass is crucial for the carbon cycle, it also has a limited storage capacity compared to other reservoirs.
3. Oceans: The oceans are the largest reservoir of carbon on Earth. They absorb large amounts of carbon dioxide from the atmosphere, mainly through a process called the oceanic carbon pump. This pump involves the absorption of carbon dioxide by marine organisms and the eventual sinking of their remains to deep ocean sediments. The oceans store carbon in various forms, including dissolved CO2, bicarbonate ions, and organic matter. This reservoir has a vast capacity to store carbon, and it plays a crucial role in regulating atmospheric carbon dioxide levels.
4. Rocks and Sediment: Rocks and sediment include both terrestrial and marine geological formations. They act as a long-term carbon sink, absorbing and storing large amounts of carbon over geologic time scales. Carbon can be stored in the form of calcium carbonate (in limestone and shells), organic matter in sediments, or as kerogen in shale deposits. While the carbon storage capacity in rocks and sediment is substantial, it is thought to be smaller compared to the other reservoirs mentioned above.
In conclusion, the oceans have the largest deposit of carbon among the options you provided.