Carbon is an essential element of life; it is necessary to form organic molecules, which are what makes up living tissue and sugars. Through photosynthesis, plants fix CO2 from the air into organic compounds, thereby incorporating it into their tissue. When an animal eats the plant, it is able to use that carbon inside its own body (animals cannot use atmospheric carbon). When the first animal is eaten by another, the carbon can then be used by the second, and so on. When plants and animals breathe, die, and decay, carbon is released back into the atmosphere in the form of CO2. This together is called the carbon cycle.
All carbon sinks and exchanges of carbon from one sink to another by various chemical, physical, geological, and biological processes. See Carbon sink and Carbon budget.
After use and recycling, wood-based products such as paper decompose, releasing carbon into the atmosphere as carbon dioxide. New forests established in place of those cut down remove carbon dioxide from the atmosphere
Carbon's movement through aquatic and terrestrial systems. 1. Carbon is assimilated in photosynthesis and lost in respiration. 2. Carbon dioxide is exchanged physically between the atmosphere and water (oceans, rivers, lakes). It is very soluble in water. About 50 times as much carbon dioxide is dissolved in the world's oceans as is contained in the atmosphere. 3. Carbon dioxide in solution is deposited in sediments (chalk, limestone, etc.).
A chain of nuclear reactions, involving carbon at its intermediate stages, that transforms four hydrogen atoms into one helium atom with a resulting release in energy. The carbon cycle is only important in stars hotter than the sun.
The circulation and reutilization of carbon atoms, especially via the processes of photosynthesis and respiration.
general term used in reference to the sum of all reservoirs and flows of carbon on Earth. The flows tend to be cyclic in nature; for example, carbon removed from the atmosphere (one reservoir) and converted into plant tissue (another reservoir) is returned back into the atmosphere when the plant is burned.
see CNO cycle
process by which carbon circulates through the environment. Carbon is part of carbohydrates, proteins and fats. Plants absorb carbon from the atmosphere, which is changed into carbohydrates via photosynthesis, and eaten by animals. Animals release carbon through respiration or decomposition, when plants or animals die.
the organic circulation of carbon from the atmosphere into organisms and back again
The circulation of carbon through ecosystems. Carbon atoms from carbon dioxide are incorporated into organic compounds formed by green plants during photosynthesis. These compounds are eventually oxidized during respiration by the plants, which made them, or by herbivores, carnivores and saprophytes, thus releasing carbon dioxide for further photosynthesis.
the flow of carbon (in its various forms, such as carbon dioxide) through the atmosphere, ocean, terrestrial biosphere, and lithosphere.
The combined processes â€“ including photosynthesis, decomposition, and respiration â€“ by which carbon moves between the atmosphere, oceans, and living organisms. For example, carbon (in the form of CO2 in plant sugar molecules) could be trapped in a plant. When that plant eventually dies and decays or burns, the carbon is once again released to the atmosphere. Living plants absorb carbon from the atmosphere, through photosynthesis, starting the cycle again. Over very long periods of time (millions of years) the biomass from plants is buried under sediment and placed under extreme pressure that allows it to eventually form coal. This carbon is then removed from the active carbon cycle. Coal can be extracted from the earth and burned, thus releasing CO2 into the atmosphere and returning it to the active cycle.
The flow of the Earth's carbon through four main reservoirs (atmosphere, terrestrial biosphere, oceans, and sediments) interconnected by pathways of exchange. (Source: Adapted from Carbon Dioxide Information Analysis Center)
the process by which carbon is taken up by plants and animals and returned to the environment in a continuous cycle.
All parts (reservoirs) and fluxes of carbon; usually thought of as a series of the four main reservoirs of carbon interconnected by pathways of exchange. The four reservoirs regions of the Earth in which carbon behaves in a systematic manner are the atmosphere, terrestrial biosphere (usually includes freshwater systems), oceans, and sediments (includes fossil fuels). Each of these global reservoirs may be subdivided into smaller pools ranging in size from individual communities or ecosystems to the total of all living organisms (biota). Carbon exchanges from reservoir to reservoir by various chemical, physical, geological, and biological processes. Source: EPO.
the cycle in which carbon moves through the biosphere, involving the exchange of carbon between the oceanic and terrestrial ecosystems, on the one hand, and the atmosphere, on the other. Scientists are seeking to understand the fluxes to and from these major carbon cycle reservoirs and how they respond to climate change. To do so, it is also necessary to understand why about half the carbon dioxide released to the atmosphere as a result of fossil fuel combustion and deforestation is accumulating in the atmosphere while the other half is held in other reservoirs such as the oceans or plants. (See also carbon dioxide (CO2), fossil fuels and sinks.)
Natural cycle of carbon dioxide to carbohydrates by photosynthesis and its return to the atmosphere by animal metabolism and decomposition
The process of transporting and transforming carbon throughout the natural life cycle of a tree from the removal Of C02 from the atmosphere to the accumulation of carbon in the tree as it grows, and the release Of C02 back into the atmosphere when the tree naturally decays or is burned.
the movement of carbon through the atmosphere, biosphere, and hydrosphere.
The sequence of transformations whereby carbon dioxide is converted to organic forms by photosynthesis or chemosynthesis, recycled through the biosphere (with partial incorporation into sediments), and ultimately returned to its original state through respiration or combustion.
is the exchange of carbon between land, atmosphere and oceans. About one quarter of the total carbon (in the form of carbon dioxide) in the atmosphere is cycled in and out each year; half of this is exchanged with the land biota, and the other half, through physical and chemical processes, across the ocean's surface.
The global scale exchange of carbon among its reservoirs in the atmosphere, oceans, vegetation, soils, and geologic deposits and minerals.
The cyclic process in which carbon and its compounds circulate through the biosphere.
the process in which carbon is recycled between the atmosphere and living things
The cycle created by the movement of the essential element carbon. Great quantities of carbon reside (are sequestered) in forests, stored in the tissues of plants. (The Amazon basin holds about 20 percent of Earth’s forest-based carbon.) When a forest is cut down or burned, carbon escapes into the atmosphere, disrupting an importance global balance. This distortion of the carbon cycle has been named as a major factor in global warming and climate change. For more on the cycle, click here.
The combined processes, including photosynthesis, decomposition, and respiration, by which carbon atoms move in a cycle involving the atmosphere, oceans, and living organisms.
A complex cycle that circulates carbon through the atmosphere, oceans, and land which includes vegetation and soil and carbon is in various forms and oxidation states throughout the cycle. [American Scientist; v78; 310-326; 1990] [Journal of Forestry; v88; 33-34; 1990
A biogeochemical cycle in which carbon and its compounds are exchanged between organisms and Earth's oceans, atmosphere, and crust. See Biogeochemical cycle.
The term used to describe the flow of carbon through the atmosphere, ocean, terrestrial biosphere and lithosphere. (6) Carbon is found in the Earth's crust in fossil fuels and carbonate rocks, in the atmosphere (mainly as carbon dioxide), in land-based ecosystems (as biomass, soils) and in the oceans. ()
All carbon reservoirs and exchanges of carbon from reservoir to reservoir by various chemical, physical, geological, and biological processes. Usually thought of as a series of the four main reservoirs of carbon interconnected by pathways of exchange. The four reservoirs, regions of the Earth in which carbon behaves in a systematic manner, are the atmosphere, terrestrial biosphere (usually includes freshwater systems), oceans, and sediments (includes fossil fuels). Each of these global reservoirs may be subdivided into smaller pools, ranging in size from individual communities or ecosystems to the total of all living organisms (biota).
A nuclear fusion reaction cycle that occurs in the cores of stars with masses greater than that of our Sun, with temperatures exceeding 16 million degrees. The reaction cycle involves carbon (C), nitrogen (N), oxygen (O), hydrogen (H) and helium (He). Hydrogen is fused into helium with the help of carbon, which acts as a catalyst to the reaction.
The sequence of transformations in which carbon dioxide is converted to organic forms by plants through photosynthesis, organic carbon is recycled through a series of living organisms, and carbon is ultimately returned to its original state (gaseous CO2) through organic matter decomposition and biological respiration. Living organisms use carbon compounds as energy sources (respiration) and as building blocks for biological molecules essential for their bodies and life functions. The carbon cycle is also important because plant nutrients follow carbon through the organic phases of this cycle, so the carbon cycle overlaps and interacts with many nutrient cycles.
The processes by which carbon is cycled through the environment. Carbon, in the form of carbon dioxide, is absorbed from the atmosphere and used by plants in the process of photosynthesis to store energy. Plants and animals then return carbon dioxide to the atmosphere through respiration when they consume this entergy. On a much long time-scale, carbon is also cycled into and out of rocks.
The movement of carbon through the surface, interior and atmosphere of the Earth.
Storage and cyclic movement of organic and inorganic forms of carbon between the biosphere, lithosphere, hydrosphere, and atmosphere.
The flow of carbon into the atmosphere and ocean, the conversion of carbonate rock, and the return by volcanoes [LCOTE