Some tree species, such as the paper birch (*Betula papyrifera*), rely on periodic forest fires to clear understory vegetation and expose mineral soil, which is necessary for their seeds to germinate. Foresters observing regions where fire suppression policies have been strictly enforced for over a century have noted a significant decline in young paper birch cohorts. However, shade-tolerant species like the sugar maple (*Acer saccharum*) have thrived in these suppressed conditions, producing dense canopies that prevent sunlight from reaching the forest floor. Given that paper birch seedlings require high levels of direct sunlight to grow into mature trees, which choice most logically completes the text?
- even if paper birch seeds manage to germinate in areas with fire suppression, the seedlings are unlikely to survive to maturity due to the shade cast by sugar maples.Cevap
- Bsugar maples will eventually replace paper birches as the dominant species in all forest ecosystems regardless of fire frequency.
- Cperiodic forest fires are the only mechanism by which understory vegetation can be cleared to allow new plant growth.
- Dyoung paper birch cohorts have declined primarily because fire suppression has increased the nutrient content of the mineral soil.
Cevap
even if paper birch seeds manage to germinate in areas with fire suppression, the seedlings are unlikely to survive to maturity due to the shade cast by sugar maples.
The correct option logically connects the premises of the passage. Since paper birch seedlings require direct sunlight to mature and sugar maples create dense canopies that block sunlight when fires are suppressed, paper birch seedlings in suppressed areas will not survive to maturity even if they manage to germinate.
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Logical Inferences
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