Newly discovered carbon may yield clues to ancient Mars

NASA's Curiosity rover landed on Mars on Aug. 6, 2012, and since then has roamed Gale Crater taking samples and sending the results back home for researchers to interpret. Analysis of carbon isotopes in sediment samples taken ...

Rise of the diatoms—a new timeline

Diatoms—tiny phytoplankton that are responsible for a fifth of all energy converted into matter by plants—may have become important much earlier in the development of Earth's ocean ecosystems and carbon cycle than previously ...

Metabolic mutations help bacteria resist drug treatment

Bacteria have many ways to evade the antibiotics that we use against them. Each year, at least 2.8 million people in the United States develop an antibiotic-resistant infection, and more than 35,000 people die from such infections, ...

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Carbon cycle

The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and atmosphere of the Earth.

The carbon cycle is usually thought of as four major reservoirs of carbon interconnected by pathways of exchange. These reservoirs are:

The annual movements of carbon, the carbon exchanges between reservoirs, occur because of various chemical, physical, geological, and biological processes. The ocean contains the largest active pool of carbon near the surface of the Earth, but the deep ocean part of this pool does not rapidly exchange with the atmosphere.

The global carbon budget is the balance of the exchanges (incomes and losses) of carbon between the carbon reservoirs or between one specific loop (e.g., atmosphere ↔ biosphere) of the carbon cycle. An examination of the carbon budget of a pool or reservoir can provide information about whether the pool or reservoir is functioning as a source or sink for carbon dioxide.

This text uses material from Wikipedia, licensed under CC BY-SA