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Question #46014
The Question
In a specific terrestrial ecosystem, an environmental anomaly causes the rate of humification to vastly exceed the rate of mineralization over a prolonged period. Based on the principles of ecosystem bioenergetics and decomposition, which of the following statements correctly predicts the cascading effect on the ecosystem?
Options
- A.
The ecosystem will experience a surge in Net Primary Productivity (NPP) because humus acts as a highly accessible colloidal reservoir of inorganic nutrients.
- B.
Secondary productivity will be severely constrained due to a 'nutrient trap' that limits the replenishment of inorganic nitrogen and phosphorus for producers.
- C.
The detritus food chain (DFC) will immediately accelerate, leading to a higher than 10% energy transfer efficiency to top carnivores.
- D.
Gross Primary Productivity (GPP) will remain unaffected, but the respiratory losses (R) of producers will decrease to compensate for nutrient immobility.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Regulatory_Failure
Understand how NOT, EXCEPT, and logical constraints are used to manipulate exam results.
Concepts Behind This Question
Humification vs Mineralization|Trophic Efficiency Limits|Secondary Productivity
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize the NCERT line that 'humus serves as a reservoir of nutrients' and mistakenly assume it promotes immediate plant growth.
The trap lies in failing to recognize that without the subsequent step of 'mineralization', these nutrients are biologically unavailable.
This creates a 'nutrient trap' that limits primary production, which logically cascades up the trophic levels to limit secondary productivity.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Ecosystem - Class 12 |
| Concept | Humification vs Mineralization |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |