Phosphorus cycling is the process by which phosphorus, an essential nutrient for plant growth and productivity, moves through different components of an ecosystem. This cycling involves various biological, chemical, and physical processes that determine the availability and distribution of phosphorus in soils, water bodies, and organisms. Phosphorus can enter ecosystems through natural processes such as weathering of rocks, or through human activities such as agricultural runoff or wastewater discharge. The cycling of phosphorus is important for ecosystem function and productivity, as well as for understanding and managing issues such as eutrophication and nutrient pollution in aquatic systems. Researchers in this field study the various pathways and mechanisms involved in phosphorus cycling, as well as the impacts of human activities on phosphorus dynamics in the environment.