In plant succession when climax is reached the net productivity

Options

A. continues to increase
B. becomes halved
C. becomes stable
D. becomes zero

Answer

**Step-by-Step Solution:**

1. **Understanding Plant Succession**: Plant succession is the process through which ecosystems change and develop over time. It involves a series of stages that lead to a stable community known as the climax community.

2. **Defining Climax Community**: The climax community is the final stage of succession, where the ecosystem reaches a stable state. This means that the species composition remains relatively constant over time, and the ecosystem is in balance.

3. **Net Productivity in Ecosystems**: Net productivity refers to the amount of organic matter (biomass) produced by plants in an ecosystem after accounting for the energy used in respiration. It is an important measure of ecosystem health and productivity.

4. **Analyzing the Options**:
- **Option 1**: "It continues to increase." This option is incorrect because, once the climax community is reached, productivity stabilizes rather than continues to increase.
- **Option 2**: "It becomes halved." This is also incorrect, as a reduction in productivity would indicate a decline in the ecosystem's health.
- **Option 3**: "It becomes stable." This option is correct. When the climax community is reached, the net productivity stabilizes, indicating a balanced ecosystem.
- **Option 4**: "Zero." This option is incorrect because a climax community does not have zero productivity; it maintains a stable level of productivity.

5. **Conclusion**: The correct answer is that when the climax is reached in plant succession, the net productivity becomes stable.

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