Many different processes occur in the carbon cycle. Photosynthesis is one of those processes that occurs everywhere on Earth. The reaction occurring during photosynthesis, with the addition of solar energy, CO2 + H2O = C6H12O6 + O2, therefore, with water and energy, some organisms can carbonate as carbon dioxide from air or water and produce sugar and oxygen. Photosynthesis occurs in terrestrial and marine plants and other autotrophic biota. Say no to plagiarism. Get a tailor-made essay on “Why Violent Video Games Should Not Be Banned”? Get an Original Essay How long carbon stays in a particular area depends on the organisms carrying out the process. For example, in marine environments, phytoplankton, which are the main autotrophic organisms, absorb carbon dioxide from the air and water and produce oxygen. However, the organisms do not live long and the carbon they have absorbed is quickly transferred to other organisms which feed on it or are deposited on the sea floor as sediment. The length of time carbon remains in terrestrial environments is much longer. On all continents, forests are the greatest conductors of photosynthesis and the carbon absorbed by trees during the process can remain there for hundreds of years, depending on the lifespan of the trees. Forests become carbon reservoirs and hold the carbon until the trees decompose or there is a fire. In forests and other terrestrial environments, smaller plants also photosynthesize and retain carbon for a much shorter period, but the carbon in these plants is often reabsorbed by surrounding plants. So, in general, in terrestrial environments, carbon absorbed by photosynthesis is often stored there longer than in marine environments. Carbon found in marine environments is generally more readily available to other parts of the carbon cycle than that in terrestrial environments..