Question

The natural reservoir of phosphorus in soils/sediments is:

• A. Ocean
• B. Air
• C. Rocks
• D. Plants

Hint:

Unlike nitrogen or carbon, phosphorus does not cycle through the air—it’s stored in rocks and moves through the lithosphere.

Answer 1

The Correct Option is C

Phosphorus is not found in the atmosphere but is stored in the form of phosphates in rocks. Through weathering, these phosphates enter the soil and water systems, making rocks the main natural reservoir of phosphorus in ecosystems.