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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 ...
The nutrient cycle is more often used in direct reference to the idea of an intra-system cycle, where an ecosystem functions as a unit. From a practical point, it does not make sense to assess a terrestrial ecosystem by considering the full column of air above it as well as the great depths of Earth below it.
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 .
The nitrogen cycle is of particular interest to ecologists because nitrogen availability can affect the rate of key ecosystem processes, including primary production and decomposition. Human activities such as fossil fuel combustion, use of artificial nitrogen fertilizers, and release of nitrogen in wastewater have dramatically altered the ...
The main driving factor of the oxygen cycle is photosynthesis, which is responsible for the modern Earth's atmospheric composition and life. The phosphorus cycle is the movement of phosphorus through the lithosphere, hydrosphere, and biosphere. The atmosphere does not play a significant role in the movements of phosphorus, because phosphorus ...
Elements other than carbon, particularly phosphorus and nitrogen, are regenerated when protozoa feed on bacterial prey [15] and this way, nutrients become once more available for use in the water column. This regeneration cycle is known as the microbial loop [16] and is a key component of lentic food webs. [2]
An example of a topological food web (image courtesy of USDA) [1]. The soil food web is the community of organisms living all or part of their lives in the soil. It describes a complex living system in the soil and how it interacts with the environment, plants, and animals.
This process is an important source for nutrients that other organisms require. Examples of these organisms include phytoplankton and algae, whose communities are often limited in growth by the availability of specific nutrients, most commonly nitrogen which is the primary limiting nutrient the Columbia River. [7]