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Question #46685
The Question
An ecologist attempts to calculate the total economic valuation of biodiversity-dependent ecosystem services for an entire continent by linearly extrapolating the calculated value of a small 100-hectare regional forest. Based on the species-area relationship, why will this linear extrapolation yield a highly inaccurate valuation?
Options
- A.
The regression coefficient (Z-value) increases to 0.6–1.2 for entire continents, meaning species richness and associated services scale as a power-law function rather than linearly.
- B.
The Z-value remains a constant 0.1–0.2 regardless of the taxonomic group or region, making linear extrapolation a massive overestimation of the actual biodiversity.
- C.
The Y-intercept (C-value) decreases significantly in large areas, indicating that ecosystem services are inversely proportional to the area surveyed.
- D.
Ecosystem services are determined by the Rivet Popper hypothesis, which states that the Z-value for any continental area is fixed at exactly 1.15.
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
Hydrarch vs Xerarch Convergence|Alien Species Invasion Impacts|Ecological Succession Climax
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize the NCERT line that 'Z-value is 0.1 to 0.2 regardless of taxonomic group or region' but miss the critical exception in the very next paragraph: 'if you analyze the species-area relationship among very large areas like the entire continents...
Z values in the range of 0.6 to 1.2'.
The question tests the synthesis of this mathematical power-law function with the applied concept of ecosystem service valuation, highlighting the trap of assuming linear biological scaling.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Ecosystem - Class 12 |
| Concept | Hydrarch vs Xerarch Convergence |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |