a decrease in the thickness of soil a decrease in the amount of erosion an increase in the bacterium population an increase in the production of oxygen
Forest fires occur in many areas due to drought conditions. If the drought conditions continue for a long period of time, which might cause the repopulation of trees to be threatened?

Options:
- a decrease in the thickness of soil
- a decrease in the amount of erosion
- an increase in the bacterium population
- an increase in the production of oxygen

a decrease in the thickness of soil