The phosphorus cycles takes place between the biosphere, hydrosphere, and geosphere. Since phosphor does not have a gaseous form, little to no phosphor is transferred through the atmosphere.[1] The availability of phosphor is dependent on the environment and is often a limiting nutrient commonly called the "disappearing nutrient."[2] Even though this "disappearing nutrient" is limited, it is an essential material for organisms. Phosphor is used for energy transfers, genetic material, membrane compositions, etc. and the amount available can affect distribution of species, primary productivity, biomass, etc. The forms that phosphor generally exist as are dissolved and particulate forms, either as inorganic or organic, and generally have low solubility. Organisms have found ways to use these different forms of phosphor, or found alternative nutrients, to deal with the availability in different environments.[3][2][4][5]
One huge impact on phosphor in the environment is human activity. Due to human activity, the N:P ratio has been altered and nutrient enrichment due to run off is associated with diverse problems. An increase in phosphor can help induce an increase in toxic algal blooms (eutrophication), loss of biodiversity, an increase in fish death, etc.[5] Two main sources of human activity altering the phosphorus cycles include agriculture and phosphorus mining.[3]
The overall cycle of phosphor is as follows: rocks weather and erode in which phosphates enter the soil and can travel to the oceans. In both land and ocean, primary producers uptake phosphate to produce organic compounds and the phosphate taken up is excreted back into the soil/water or gets put back through decomposition of an organism.[3]
Terrestrial Phosphorous Cycle edit
There are three dominant pools of phosphor in terrestrial ecosystems: continental bedrock, soil, and biomass. An important sink within those pools is in the Earth's crust where a majority of phosphor is in apatite. Organic phosphor that can be found in soils and sediments are in biomass and are predominantly as orthophosphate monoesters. These orthophosphate monoesters play a key role in photosynthesis.[1]
Phosphorus regulation in soil edit
Phosphor is controlled and regulated by physical, chemical, or biological processes. Environmental factors that affect availability of phosphor include weathering and erosion, different rock types, soil pH, precipitation, deforestation and habitat loss, temperature, decomposition rates, etc.[1][2]
An important regulation of phosphor includes carbonates in the soil. Calcium carbonate effects phosphor at three different levels: elemental, surface, and environmental. Phosphor is adsorbed on carbonate minerals either as a fast reaction or a slow reaction, as obligate adsorption or partly multilayer adsorption, by binding to free metals found on carbonate sites. These metals typically include either Mg2+ or Ca2+.[1][2]
Marine Phosphorous Cycle edit
Oceans primarily receive phosphor through continental weathering, generally in dissolved and particulate phases. Another method is atmospheric deposition to remote locations in the oceans. This is important, but since phosphor does not have a gaseous form this is a very small percentage of phosphorus transfer, but is important for the open ocean where nutrients are limited.[4][5] Within the ocean, some important forms of phosphor include: dissolved inorganic phosphor (DIP), phosphate, dissolved organic phosphor (DOP), etc.[2][3] DOP is highly utilized and a valuable commodity for marine microbes, as well as can be re-mineralized twice as fact compared to other dissolved nutrients (like carbon or nitrogen).[2] The largest transport of phosphor is through biological uptakes; organic matter burials. Other mechanisms of phosphor transport include phosphor sorption and precipitation, phosphorite burial, and even hydrothermal processes. [3] Upwellings within the oceans can also serve as a negative feedback mechanism for oceanic phosphor mass balance.[6]
P availability affects on microbes edit
Limited phosphor availability in the ocean has induced microorganisms to be flexible. Some adaptations that have been used include phosphorus conservations, phosphorus limitation responses, and phosphorus niche partitioning. Plankton, for example, can use phosphor free alternatives instead of phosphor lipids when they are phosphor starved. Some prokaryotes can use a periplasmic buffer to secure phosphor and there are also picocyanobacteria that contain a large number of high affinity phosphate binding proteins.[2][7]
P availability affects on Biogeochemical cycles edit
Limited availability of phosphor also affects other nutrient cycles. One way is by influencing carbon fixation during photosynthesis, leading to an influence on export production and global climate; [5] carbon flow has a dependence on the amount of DOP available. The nitrogen cycle is also impacted by DOP availability in that using DOP can provide an advantage to N2 fixing microbes.[2]
Human Impacts on the Phosphorus Biogeochemical Cycle edit
Agriculture has a huge impact on the phosphorus cycle. There are fertilizers made to help combat phosphor limitations from mining phosphorus rocks, leading to excess phosphor being washed into rivers and groundwater from both the fertilizers in crop production and the erosion of the rocks. Since the pre-anthropogenic era, the flux of phosphor has at least doubled. A few issues come with this phosphor output. Anthropogenic activities can drive Eutrophication (can increase with an increase in phosphor levels, though not as affected as with an increase in nitrogen levels), limited regions to phosphor limited regions, and even cause a loss of biodiversity.[5][2]
References edit
- ^ a b c d Cite error: The named reference
:0was invoked but never defined (see the help page). - ^ a b c d e f g h i Cite error: The named reference
:1was invoked but never defined (see the help page). - ^ a b c d e Cite error: The named reference
:2was invoked but never defined (see the help page). - ^ a b Cite error: The named reference
:3was invoked but never defined (see the help page). - ^ a b c d e Cite error: The named reference
:4was invoked but never defined (see the help page). - ^ Cite error: The named reference
:6was invoked but never defined (see the help page). - ^ Cite error: The named reference
:5was invoked but never defined (see the help page).
[1][2][3][4][5][6][7][8][9][10][11]
- ^ "Phosphorus - Understanding Global Change". University of California Museum of Paleontology. September 10, 2020.
- ^ Duhamel, Solange; Diaz, Julia M.; Adams, Jamee C.; Djaoudi, Kahina; Steck, Viktoria; Waggoner, Emily M. (2021). "Phosphorus as an integral component of global marine biogeochemistry". Nature Geoscience.
- ^ Geng, Yuanyuan; Pan, Shang; Zhang, Lin; Qiu, Jingjing; He, Kun; Gao, Hongjian; Li, Zhen; Tian, Da (November 2022). "Phosphorus biogeochemistry regulated by carbonates in soil". Science Direct.
- ^ Dyhrman, S.T., J.W. Ammerman, and B.A.S. Van Mooy. 2007. Microbes and the marine phosphorus cycle. Oceanography 20(2):110–116, https://doi.org/10.5670/oceanog.2007.54.
- ^ Delaney, M. L. "Phosphorus accumulation in marine sediments and the oceanic phosphorus cycle". Advancing Earth and Space Sciences.
- ^ Paytan A, McLaughlin K. The oceanic phosphorus cycle. Chem Rev. 2007 Feb;107(2):563-76. doi: 10.1021/cr0503613. Epub 2007 Jan 27. PMID 17256993.
- ^ Benitez-Nelson, Claudia R. "The biogeochemical cycling of phosphorus in marine systems". Science Direct.
- ^ Jusino-Maldonado, Marcos; Rianço-Silva, Rafael; Mondal, Javed Akhter; Pasek, Matthew; Laneuville, Matthieu; Cleaves II, H. James (2022). "A global network model of abiotic phosphorus cycling on Earth through time".
- ^ Sosa, Oscar A. (December 14, 2017). "Phosphorus redox reactions as pinch hitters in microbial metabolism". PNAS.
- ^ Lomas, M. W., Burke, A. L., Lomas, D. A., Bell, D. W., Shen, C., Dyhrman, S. T., and Ammerman, J. W.: Sargasso Sea phosphorus biogeochemistry: an important role for dissolved organic phosphorus (DOP), Biogeosciences, 7, 695–710, https://doi.org/10.5194/bg-7-695-2010, 2010.
- ^ Schlesinger, William H.; Bernhardt, Emily S. (2020). "Chapter 12 - The Global Cycles of Nitrogen, Phosphorus and Potassium". Science Direct.