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Energy flow is the flow of energy through living things within an ecosystem. [1] All living organisms can be organized into producers and consumers, and those producers and consumers can further be organized into a food chain. [2][3] Each of the levels within the food chain is a trophic level. [1] In order to more efficiently show the quantity ...
Nitrogen fixation is a chemical process by which molecular dinitrogen (N. 2) is converted into ammonia (NH. 3). [1] It occurs both biologically and abiologically in chemical industries. Biological nitrogen fixation or diazotrophy is catalyzed by enzymes called nitrogenases. [2]
The mean chain length of an entire web is the arithmetic average of the lengths of all chains in a food web. [43] [15] In a simple predator-prey example, a deer is one step removed from the plants it eats (chain length = 1) and a wolf that eats the deer is two steps removed from the plants (chain length = 2).
Actinorhizal plants are distributed within three clades, [1] and are characterized by nitrogen fixation. [2] They are distributed globally, and are pioneer species in nitrogen-poor environments. Their symbiotic relationships with Frankia evolved independently over time, [3] and the symbiosis occurs in the root nodule infection site.
Nitrogen is a vital macronutrient for plants, necessary for the biosynthesis of many basic cellular components, such as DNA, RNA and proteins. Nitrogen is obtained by plants through roots from inorganic or organic sources, such as amino acids. [1] In agricultural settings, nitrogen may be a limiting factor for plant growth and yield, and in ...
The nitrogen cycle is the biogeochemical cycle by which nitrogen is converted into multiple chemical forms as it circulates among atmospheric, terrestrial, and marine ecosystems. The conversion of nitrogen can be carried out through both biological and physical processes. Important processes in the nitrogen cycle include fixation ...
A nutrient cycle (or ecological recycling) is the movement and exchange of inorganic and organic matter back into the production of matter. Energy flow is a unidirectional and noncyclic pathway, whereas the movement of mineral nutrients is cyclic. Mineral cycles include the carbon cycle, sulfur cycle, nitrogen cycle, water cycle, phosphorus ...
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 ...