Answer with Explanation:
When phosphorus is carried by run-off to the oceans, marine animals take them in while others fall down to the ocean floor and attaches to sediments. Overtime, the ocean floor accumulates these particles resulting to the formation of sedimentary rocks (layers).
Weathering is a natural process and this can occur in the ocean. When this happens, the phosphorus which have been embedded in the sedimentary rocks are uplifted to the shore and thus, it goes back to the land. Then, the cycle starts again. The plants will take them up, then the animals will eat the plants in order to obtain it. When the plants and animals die, it will then be brought back to the soil or carried by run-off to the oceans.