Advanced Placement (AP) Human Geography Practice Exam

Which agricultural practice is most likely to lead to soil depletion?

1. Diversification of crops

2. Crop rotation

3. Monoculture

4. Permaculture

The correct answer is: Monoculture

Monoculture is an agricultural practice that involves growing a single crop species over a large area for many consecutive years. This practice can lead to soil depletion for several reasons. First, when the same crop is planted repeatedly, it continually extracts specific nutrients from the soil, which can become depleted over time if those nutrients are not replenished through fertilization or other means. Additionally, monoculture often results in reduced biodiversity in the soil, making it less resilient to pests and diseases. The lack of crop variety means that there are fewer different root structures and plant life to help maintain soil health, which can lead to erosion and reduced organic matter in the soil. While diversification of crops, crop rotation, and permaculture contribute to sustainable soil management by promoting biodiversity, improving soil structure, and enhancing nutrient cycling, monoculture tends to create a dependency on synthetic fertilizers and pesticides to maintain yield, which can further degrade soil health in the long run.