Biogeochemical cycle having a small gaseous component is found in

Options

A. Phosphorus
B. Nitrogen
C. Carbon
D. Sulfur

Answer

To solve the question regarding which biogeochemical cycle has a small gaseous component, we can analyze the options provided:

1. **Phosphorus Cycle**:
- The phosphorus cycle is primarily a sedimentary cycle. It involves the weathering of rocks, erosion, and transportation of phosphorus in soil and water. There is no significant gaseous phase in the phosphorus cycle.

2. **Nitrogen Cycle**:
- The nitrogen cycle includes a significant gaseous component. Nitrogen exists in the atmosphere as N2 and is involved in processes like nitrogen fixation and denitrification. Therefore, it does not fit the criteria of having a small gaseous component.

3. **Carbon Cycle**:
- The carbon cycle also has a substantial gaseous component. Carbon dioxide (CO2) is a major part of this cycle, as it is exchanged between the atmosphere, oceans, and living organisms. Thus, this cycle cannot be considered as having a small gaseous component.

4. **Sulfur Cycle**:
- The sulfur cycle includes both sedimentary and gaseous phases. Sulfur can be found in the atmosphere in the form of sulfur dioxide (SO2) and hydrogen sulfide (H2S), but the gaseous component is relatively small compared to its sedimentary component. This makes the sulfur cycle the best fit for the question.

Based on this analysis, the correct answer is **sulfur**.

### Step-by-Step Solution:
1. **Identify the cycles**: Review the four biogeochemical cycles mentioned: phosphorus, nitrogen, carbon, and sulfur.
2. **Analyze the phosphorus cycle**: Note that it is primarily sedimentary with no significant gaseous component.
3. **Analyze the nitrogen cycle**: Recognize that it has a large gaseous component due to nitrogen gas (N2) in the atmosphere.
4. **Analyze the carbon cycle**: Acknowledge that it also has a significant gaseous component with carbon dioxide (CO2).
5. **Analyze the sulfur cycle**: Understand that it has both sedimentary and gaseous phases, but the gaseous component is relatively small.
6. **Conclude the answer**: Determine that the sulfur cycle is the correct answer as it fits the criteria of having a small gaseous component.