Question

which effect did fire have on plant species biodiversity in the hawaiian mountain shrubland?
a. only the native shrubs increased after repeated fires, increasing the biodiversity of the area.
b. fire did not affect the plant species biodiversity of the nonnative fountain grass or the native shrubs
c. plant species biodiversity decreased until only nonnative fountain grass remained after repeated fires
d. fire increased plant species biodiversity by allowing fountain grass to keep growing within an area of native shrubs

Explanation:

• Analyze each option:
• Option A: Before the first fire, native shrubs had 20% cover. After one - year, it was 4%, and after repeated fires, 0%. Non - native fountain grass had 50% before the first fire, 30% after one - year, and 100% after repeated fires. So, the native shrubs did not increase after repeated fires.
• Option B: Fire clearly affected the plant species as shown by the changes in cover percentages of native shrubs and non - native fountain grass.
• Option C: Plant species biodiversity decreased for native shrubs (from 20% to 0%) and non - native fountain grass first decreased (from 50% to 30%) then increased (to 100%), but overall, it's not that only non - native fountain grass remained.
• Option D: Fire decreased the cover of native shrubs (from 20% to 0%) and initially decreased then increased the cover of non - native fountain grass. But it did not increase plant species biodiversity.

Answer:

C. plant species biodiversity decreased until only nonnative fountain grass remained after repeated fires.