3rd December 2025
Phosphorus is another key mineral for the health of plants and animals. It derives from rocks and through erosion finds its way into the soil, where as soluble phosphates (HPO4 and H20P4) it is absorbed by plants, and through eating plants into plant eating creatures and so up through the food chain. Bacteria in the soil aid the absorption of phosphates.
Organic phosphorus is released back into the soil through defecation and the decay of plants and animals. During the process of decomposition the organic form of phosphorus is converted to an inorganic firm such that it can overtime be reformed into sedimentary rocks. This comprises the natural phosphorus cycle.
Because phosphorus improves crop yields it is added as an artificial fertiliser. This input disrupts the cycle. Excess of phosphorus is the primary cause of algal bloom in water sources, reducing the amount of oxygen present and so killing off many plants and creatures. (1)
The following data comes from Planetary Boundaries Science:-
“Before human intervention, phosphorus flows were low ~2.5 Tg P pa (tetragrams of phosphorus per year) from land to freshwater and ~1.3 Tg P pa of export to the ocean. Human activities have increased flows from land to freshwater systems through a global application of mined phosphorus to cropland of around 18.2 Tg P pa and have increased phosphorus flows to the ocean to around 4.4 Tg P pa, largely due to fertiliser use.”
At the same time, the sage planetary boundary for phosphorus flow is between 6.2 and 11 Tg P pa. (2)
- https://biologyteach.com/phosphorus-cycle/
- https://www.planetaryhealthcheck.org/boundary/modification-of-biogeochemical-flows/
The Green Tau 