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Question #46666
The Question
Read the following statements regarding ecological succession and biogeochemical cycling. Which of the following statements is INCORRECT?
Options
- A.
Both hydrarch and xerarch successions ultimately converge to a similar mesic climax community, which is theoretically in equilibrium with the environment.
- B.
In a mature climax ecosystem, the net community productivity approaches zero as gross primary productivity is largely balanced by total community respiration.
- C.
The climax community maintains absolute static equilibrium because sedimentary cycles, such as the phosphorus cycle, become perfectly closed loops, preventing any nutrient loss to the reservoir sink.
- D.
Unlike the carbon cycle, the atmospheric input of phosphorus through rainfall is much smaller, and gaseous exchange of phosphorus between organisms and the environment is negligible.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Comparative_Analysis
Sharpen your ability to evaluate multiple scenarios and distinguish between competing potential answers.
Concepts Behind This Question
Decomposition Rate Modifiers|Humification vs Mineralization|Ecological Succession Climax
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often misinterpret the NCERT statement 'the climax community is in equilibrium with the environment' to mean a perfectly closed, self-sustaining utopian ecosystem (absolute static equilibrium).
This trap exposes the failure to integrate the thermodynamic and biogeochemical constraints of 'imperfect' sedimentary cycles, where nutrient immobility (sequestration in sediments) prevents a 100% closed loop, making true static equilibrium a theoretical impossibility.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Ecosystem - Class 12 |
| Concept | Decomposition Rate Modifiers |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |