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The phosphorus cycle is the biogeochemical cycle that involves the movement of phosphorus through the lithosphere, hydrosphere, and biosphere.Unlike many other biogeochemical cycles, the atmosphere does not play a significant role in the movement of phosphorus, because phosphorus and phosphorus-based materials do not enter the gaseous phase readily, [1] as the main source of gaseous phosphorus ...
Water is the medium of the oceans, the medium which carries all the substances and elements involved in the marine biogeochemical cycles. Water as found in nature almost always includes dissolved substances, so water has been described as the "universal solvent" for its ability to dissolve so many substances.
II) An equilibrium between seawater and planktonic nutrient pools is maintained through biotic feedback mechanisms. [ 1 ] [ 3 ] Redfield proposed a thermostat like scenario in which the activities of nitrogen fixers and denitrifiers keep the nitrate to phosphate ratio in the seawater near the requirements in the protoplasm. [ 4 ]
A biogeochemical cycle, or more generally a cycle of matter, [1] is the movement and transformation of chemical elements and compounds between living organisms, the atmosphere, and the Earth's crust. Major biogeochemical cycles include the carbon cycle, the nitrogen cycle and the water cycle. In each cycle, the chemical element or molecule is ...
The ocean plays a key role in the water cycle as it is the source of 86% of global evaporation. [2] The water cycle involves the exchange of energy, which leads to temperature changes. When water evaporates, it takes up energy from its surroundings and cools the environment. When it condenses, it releases energy and warms the environment.
In addition to carbon, organic matter found in phytoplankton is composed of nitrogen, phosphorus and various trace metals. The ratio of carbon to nitrogen and phosphorus varies from place to place, [14] but has an average ratio near 106C:16N:1P, known as the Redfield ratio. Trace metals such as magnesium, cadmium, iron, calcium, barium and ...
In most hydrogen-fusing stars, including the Sun, a chemical cycle involved in stellar nucleosynthesis occurs which is known as a carbon-nitrogen-oxygen or . In addition to this cycle, stars also have a helium cycle. [1] Various cycles involving gas and dust have been found to occur in galaxies. [2]
Due to this, these methods make one key assumption which is that all fluxes into a given intracellular metabolite pool balance all the fluxes out of the pool. [ 5 ] This assumption means that for a given metabolic network the balances around each metabolite impose a number of constraints on the system.