Question 1
The phosphorus cycle is fundamentally different from the nitrogen and sulfur cycles. How so?
- The phosphorus cycle does not include a gaseous phase, resulting in no significant quantities of atmospheric phosphorus.
- Phosphorus is not fixed in the atmosphere by lightning.
- Phosphorus does not enter the cycle from weathering of sediments and parent material.
- Phosphorus is not taken up by plants and is a strictly inorganic cycle.
- Phosphorus is cycled back into the soil through precipitation.
Explanation: The phosphorus cycle does not contain an atmospheric phase, while both the sulfur and nitrogen cycles do.