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Question #46678
The Question
During primary succession on a newly exposed bare rock (xerosere), the pioneer lichen community establishes successfully but experiences severe nutrient immobility, failing to accumulate organic matter or fix atmospheric nitrogen. Based on the principles of ecological succession, which of the following will be the most likely consequence?
Options
- A.
The community will bypass the bryophyte stage and directly establish a drought-resistant xerophytic climax community.
- B.
The facilitation mechanism will fail, leading to an arrested successional state that prevents the invasion of bryophytes.
- C.
Intermediate seral species will invade and competitively exclude the lichens through the tolerance model of succession.
- D.
The successional trajectory will spontaneously shift to a hydrosere due to the lack of organic soil to absorb water.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Evolutionary_Exception
Tackle problems where standard rules evolve or change based on specific environmental constraints.
Concepts Behind This Question
Primary Succession|Climax Community|Nutrient Mineralization
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often harbor the misconception that ecological succession is an unstoppable, time-dependent chronological sequence.
The critical pivot here is recognizing that succession is strictly driven by biological habitat modification (Facilitation).
If the pioneer species fail to alter the edaphic (soil) conditions due to nutrient immobility, the entire successional domino effect breaks down, proving that succession is condition-dependent, not merely time-dependent.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Ecosystem - Class 12 |
| Concept | Nutrient Cycling Reservoirs |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |