考场机经 test64
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Seeding a forest with nonnative species after a fire can impede native plant regeneration and spread invasive species in vulnerable fire-affected soils. Moreover, native seed sources are almost always sufficient for early nature reestablishment of native species, so planting should be considered only when natural regeneration is unlikely. Replanting dense stands of fast-growing confers--a common postfire management practice--truncates the biologically rich early stage of ecological succession and can increase the severity of future fires. Other treatments should be carefully scrutinized for their potential to spread noxious weeds. For instance, straw much applied extensively to reduce erosion after the 2002 Hayman Fire in Colorado was contaminated with cheatgrass, an invasive grass difficult to control or eradicate once established.

According to the passage, which of the following is a consequence of replanting an area with dense stands of fast-growing confers after a fire?
A
The normal progression of ecological development will be affected.
B
The conifers will be slower growing than if they had been less densely planted.
C
Subsequent fires may be more severe than they would have been if such a replanting had not been done.
Select one or more answer choices.
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1.未作答
正确答案
1.A C
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