Question

question 23 (1 point)
which type of succession would occur after a forest fire that burns trees but leaves soil intact?

a primary succession
b secondary succession

question 24 (1 point)
match each example to primary or secondary succession:

column a
1 lichen growing on bare rock after a volcanic eruption
2 a forest regrowing after a wildfire
3 plants colonizing a glacier retreat area
4 grasses and shrubs growing in an abandoned farm field
column b
a secondary succession
b primary succession

Explanation:

Question 23

To determine the type of succession after a forest fire that leaves soil intact, we recall:

• Primary succession occurs on newly formed, lifeless substrates (e.g., bare rock, volcanic ash) with no soil.
• Secondary succession occurs in areas where a disturbance (like a fire) destroys life but leaves soil and some organisms/seed bank intact.

A forest fire that burns trees but leaves soil intact fits secondary succession, as soil (and potential seeds/organisms) remains.

1. Lichens on bare rock (volcanic eruption): Bare rock has no soil, so this is primary succession (starts from lifeless substrate).
2. Forest regrowing after wildfire: Wildfire destroys life but leaves soil, so secondary succession.
3. Plants colonizing glacier retreat area: Glacier retreat exposes bare rock (no soil), so primary succession.
4. Grass/shrubs in abandoned farm field: Farm fields have soil (from previous agriculture), so secondary succession (disturbance: abandonment, soil remains).

Answer:

b. Secondary succession

Question 24