摘要：Carbon is one of the most important elements that controllife and the environment of Earth. The atmosphere and biosphere, however, are very small C reservoirs. By contrast, themantle has 27,000 examoles C, whereas the total Earth surface (mostly sediments including fossil fuels) has~7350 examoles C, with only 0.07 in the atmosphere and 0.13in the biosphere and 3.3 in the hydrosphere (Hayes andWaldbauer, 2006). Therefore, carbon exchanges between themantle and the surface, which are dominated by magmatism(outgassing) and plate subduction (down going), are the keysthat strongly influence long term climate changes and theinhabitability of Earth.
