How does the phosphorus cycle affect humans?

Humans and the phosphorous cycle affect each other.

People need phosphorous in the form of phosphates to survive. Adenosine triphosphate is a molecule used whenever we move or use energy in ion channels, and contains phosphate groups. Calcium phosphate makes up about 70% of our bones. Phosphate is also in the backbone of our DNA and RNA.

Organisms get phosphate through plant life in the phosphorous cycle. Producers (plant life) take up minerals from the soil that contain phosphorous, and the molecules travel around the plant. It is then eaten by a primary consumer such as a deer, or even goes straight to the human. Through a chain of one organism eating another and receiving the nutrients inside it, humans eventually get phosphorous.

Any nutrients that aren't taken up in consumption disperse into the soil or are consumed by bacteria and organic phosphates turned to inorganic phosphates before being returned to the water column. It can then be taken up by plants and used again, some amount of it making its way back to people.

The phosphorous cycle is absolutely essential to humans.

However, humans have also affected the phosphorous cycle through mining, fertilisers and pollution with fuels. Fertiliser is rich in phosphorous, and when used on fields it can then spread into the surrounding environment, causing areas of hypertrophication where algae grow in excess, which can be bad for the ecosystem.

Phosphorous used in fertilisers is mostly mined from calcium phosphate. Mining also uses fuel, and phosphorous that becomes buried in the lithosphere in oil and coal as an impurity can be burned by accident and released into the atmosphere as phosphorous compounds. See this question to learn more.

The phosphorus cycle affects humans primarily through its role in agriculture, as phosphorus is essential for plant growth. It is also important in the production of fertilizers and contributes to water pollution when excess phosphorus from agricultural runoff enters water bodies, leading to eutrophication. Additionally, phosphorus is crucial for human health, as it is a component of DNA, RNA, and ATP, which are vital for cellular function and energy metabolism.