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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 ...
Nutrients in the soil are taken up by the plant through its roots, and in particular its root hairs.To be taken up by a plant, a nutrient element must be located near the root surface; however, the supply of nutrients in contact with the root is rapidly depleted within a distance of ca. 2 mm. [14] There are three basic mechanisms whereby nutrient ions dissolved in the soil solution are brought ...
Plants can increase phosphorus uptake by a mutualism with mycorrhiza. [6] On some soils, the phosphorus nutrition of some conifers, including the spruces, depends on the ability of mycorrhizae to take up, and make soil phosphorus available to the tree, hitherto unobtainable to the non-mycorrhizal root. Seedling white spruce, greenhouse-grown in ...
The dry matter consists mainly of carbon, oxygen, and hydrogen. Although these three elements make up about 92% of the dry weight of the organic matter in the soil, other elements present are essential for the nutrition of plants, including nitrogen, phosphorus, potassium, sulfur, calcium, magnesium, and many micronutrients. [1]
Following the Greeks, the idea of a hydrological cycle (water is considered a nutrient) was validated and quantified by Halley in 1687. Dumas and Boussingault (1844) provided a key paper that is recognized by some to be the true beginning of biogeochemistry, where they talked about the cycle of organic life in great detail.
This process generally produces CO 2, water and a collection of simple nutrients like nitrate or phosphate that can then be taken up by other organisms. The above general form, when considering O 2 as the oxidant, is the equation for respiration.
This mineral nitrogen is said to be immobilized. This may reduce the concentration of inorganic nitrogen in the soil and thus the nitrogen is not available to plants. As carbon dioxide is released during the generation of energy in decomposition, a process called "catabolism", the C:N ratio of the organic matter decreases. When the C:N ratio is ...
Plants hold soil against erosion, and accumulated plant material build soil humus levels. Plant root exudation supports microbial activity. Animals serve to decompose plant materials and mix soil through bioturbation. [70] Soil is the most speciose (species-rich) ecosystem on Earth, but the vast majority of organisms in soil are microbes, a ...