Mystery of Phosphorous cycle

Phosphorus is an essential element for life and is needed in large quantities by animals. It is present in all living cells and is required for the function of many enzymes. It is also important for the formation of DNA and RNA, cell membranes, and neurotransmitters. With such immense importance, it is natural to wonder how phosphorous finds its way into our lives. With this objective let us have a look at the journey of phosphorous and the various steps involved in the phosphorous cycle.

In the human body, phosphorus is primarily found in the skeleton and teeth.

Phosphorous Cycle

Firstly, the cycling of nutrients in and out of a system is an important part of what makes up a healthy ecosystem. Secondly, this cycling of nutrients through ecosystems is often referred to as nutrient cycling. In a healthy ecosystem, nutrients are recycled over time, and new nutrients are added through the actions of living things. Additionally, the nutrient cycles are also known as biogeochemical cycles.

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The phosphorous cycle is a sedimentary biogeochemical cycle. This implies that the reservoir for phosphorous is located in the Earth’s crust, as opposed to gaseous cycles whose reservoir exists in the atmosphere.

Rocks are the primary source of phosphorous.

Steps involved in Phosphorous Cycle

The phosphorous cycle involves the uptake of inorganic and organic phosphorous compounds, the transformation of these compounds into cellular components and the eventual release of the elements back into the environment. Another key point is that the cycle is a key part of an organism’s metabolism and is particularly important in the growth and development of living organisms.

Let’s look at each step one by one:-

1. Weathering of rocks

To begin with, rocks contain phosphorous in the form of phosphates. Various microorganisms, as well as external physical factors, can be responsible for the solubilization of rocks. As these rocks weather, the phosphates dissolve in the soil. This soil solution is then taken up by the plants (roots). 

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2. Absorption by Plants 

The soil solution containing phosphates and other minerals is absorbed particularly by the plants. The phosphates are then particularly assimilated into the plant body and used to form various organic compounds. Hence, plants become the source of phosphates for all the other organisms.

Image Source: https://www.frontiersin.org/articles/10.3389/fpls.2020.00413/full

3. Movement of Phosphorus in the food chain

Phosphates find their way from plants to animals through consumption by herbivores and other animals. These are then passed on from consumer to consumer, rising up in the food chain. Another key point is that the consumers use these phosphates for the synthesis of essential biomolecules such as DNA, RNA and ATP. 

Also read: The secret life of Honey fungus – My Biology Dictionary

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4. Return of phosphorous to the ecosystem 

For the phosphate cycle to run seamlessly, it is necessary that the phosphates that were originally taken up from the Earth’s crust return to their primary reservoir. This is accomplished particularly by numerous decomposing and saprophytic microorganisms that degrade the dead remains and waste material of plants and animals. Subsequently, the phosphates end up back in the earth’s crust, ready to restart their journey.

Image Source: https://www.researchgate.net/figure/The-phosphorus-cycle-various-sources_fig49_216333102

Future Scope

Phosphorus is an indispensable element in the biosphere. It is a central component of the backbone of all cellular proteins and is an important building block for DNA and RNA. Each of the steps involved in the phosphorous cycle has great significance in maintaining the balance of phosphorous in the ecosystem.

To summarize, with such a key role in the existence of life on Earth, it is alarming that agricultural systems are leading to a global phosphorous shortage which will surely limit the future food and feed production. Overuse of chemical fertilizers has led to phosphorous deficiency and water pollution. Hence, appropriate management of phosphorous is an important aspect not only for higher yields but also for environmental protection.

Hope you had fun on this journey of Phosphorous through the ecosystem.

Keep reading for more biogeochemical cycles!

Team MBD

Gather more information at-Phosphorus cycle – AccessScience from McGraw-Hill Education